Publications by authors named "Jonathan A C Sterne"

185 Publications

Managing NSTEMI in older patients - Authors' reply.

Lancet 2021 01;397(10272):371-372

National Institute for Health Research Imperial Biomedical Research Centre, Imperial College London and Imperial College Healthcare NHS Trust, London W2 1NY, UK. Electronic address:

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http://dx.doi.org/10.1016/S0140-6736(20)32393-XDOI Listing
January 2021

Repurposed Antiviral Drugs for Covid-19 - Interim WHO Solidarity Trial Results.

N Engl J Med 2021 02 2;384(6):497-511. Epub 2020 Dec 2.

The affiliations of the members of the writing and steering committees are as follows: the Nuffield Department of Population Health and Medical Research Council Population Health Research Unit, University of Oxford, Oxford (H.P., R.P.), and the University of Bristol, Bristol (E.A., S.B., H.B.C.C.-P., D.H., J.K., C.A.R., J.A.C.S.) - both in the United Kingdom; the World Health Organization, Geneva (A.-M.H.-R., M.-P.P., V.S., P. Lydon, M.C.M.-M., K.S., S.S.), the University of Bern, Bern (S.A., M.B., S. McGinty, S.T.), and Lausanne University Hospital, Lausanne (O.M.) - all in Switzerland; the Centre for the AIDS Programme of Research in South Africa, Durban (Q.A.K.), and the University of the Witwatersrand (J.N.) and the Wits Reproductive Health and HIV Institute (H.R.), Johannesburg - all in South Africa; the Institute of National Epidemiology, National Institutes of Health, University of the Philippines, Manila (M.M.A.); the Agency of Medicine and Medical Devices (C.H.G.) and Hospital Clínico San Carlos, Universidad Complutense de Madrid, Spanish Clinical Research Network, Instituto de Investigación Sanitaria San Carlos (A.P.), Madrid; INSERM, Paris (M.-P.K.), and Hospices Civils de Lyon, Lyon (F.A.) - both in France; the Digestive Disease Research Institute, Tehran University of Medical Sciences, Tehran, Iran (R.M.); the University of British Columbia, Vancouver (S. Murthy), and the Public Health Agency of Canada, Ottawa (M.I.S.) - both in Canada; the Public Health Foundation of India, New Delhi (K.S.R.), and the Indian Council of Medical Research, National AIDS Research Institute, Pune (S.G.) - both in India; the National Academy of Sciences of Buenos Aires (M.R.P.) and Fundación del Centro de Estudios Infectológicos (G.L.), Buenos Aires; Rafic Hariri University Hospital (P.A.H.) and the Ministry of Public Health (R.H.), Beirut, Lebanon; the Ministry of Health (A.M.A.-B.) and Infectious Diseases Hospital (A. Alhasawi), Kuwait City, Kuwait; Universidad Nacional de Colombia and Clinica Colsanitas (C.A.A.-M.) and the Ministry of Health (M.L.M.R.), Bogota, Colombia; the Ministry for Preventive Health, Riyadh, Saudi Arabia (A. Asiri, A. Alotaibi); Oslo University Hospital (P.A., A.B.-D.) and Research Council of Norway (J.-A.R.), Oslo; Secretaria de Salud de Honduras (N. Cerrato) and the National Autonomous University of Honduras (M.T.M.), Tegucigalpa; Penang Hospital, Penang (T.S.C.), and Hospital Sungai Buloh and Jalan Hospital, Selangor (S.K.) - both in Malaysia; University Hospital Center Mother Theresa (N. Como) and the National Agency for Medicines and Medical Devices (N.S.), Tirana, Albania; the HRB Clinical Research Facility, University College Cork, Cork (J.E.), and the Department of Health and Children, Dublin (P. Lennon, T.M.) - both in Ireland; Universidad Peruana Cayetano Heredia, Lima, Peru (P.J.G., E.G.); Vilnius University Hospital Santaros Klinikos (L.G.) and Vilnius University, Institute of Clinical Medicine (L.J.), Vilnius, Lithuania; Shaukat Khanum Memorial Cancer Hospital and Research Center, Lahore, Pakistan (M. Hassan, A.R.); the National Hepatology and Tropical Medicine Research Institute (M. Hassany) and the Ministry of Health and Population (H.Z.), Cairo; the National Institute of Health Research and Development (I.I.) and Rumah Sakit Umum Pusat Persahabatan (M.R.R.), Jakarta, Indonesia; the Italian Medicines Agency, Rome (N.M.), and the University of Verona, Verona (E.T.) - both in Italy; the Ministry of Health (S. Manevska) and the University Clinic of Infectious Diseases and Febrile Conditions (M.S.), Skopje, North Macedonia; the Oswaldo Cruz Foundation, Rio de Janeiro (E.P.N., P.P.S.R.); and the Finnish Institute for Health and Welfare and the University of Finland (M.P.) and Helsinki University Hospital (K.A.O.T.), Helsinki, and South Karelian Central Hospital, Lappeenranta (K.A.O.T.) - all in Finland.

Background: World Health Organization expert groups recommended mortality trials of four repurposed antiviral drugs - remdesivir, hydroxychloroquine, lopinavir, and interferon beta-1a - in patients hospitalized with coronavirus disease 2019 (Covid-19).

Methods: We randomly assigned inpatients with Covid-19 equally between one of the trial drug regimens that was locally available and open control (up to five options, four active and the local standard of care). The intention-to-treat primary analyses examined in-hospital mortality in the four pairwise comparisons of each trial drug and its control (drug available but patient assigned to the same care without that drug). Rate ratios for death were calculated with stratification according to age and status regarding mechanical ventilation at trial entry.

Results: At 405 hospitals in 30 countries, 11,330 adults underwent randomization; 2750 were assigned to receive remdesivir, 954 to hydroxychloroquine, 1411 to lopinavir (without interferon), 2063 to interferon (including 651 to interferon plus lopinavir), and 4088 to no trial drug. Adherence was 94 to 96% midway through treatment, with 2 to 6% crossover. In total, 1253 deaths were reported (median day of death, day 8; interquartile range, 4 to 14). The Kaplan-Meier 28-day mortality was 11.8% (39.0% if the patient was already receiving ventilation at randomization and 9.5% otherwise). Death occurred in 301 of 2743 patients receiving remdesivir and in 303 of 2708 receiving its control (rate ratio, 0.95; 95% confidence interval [CI], 0.81 to 1.11; P = 0.50), in 104 of 947 patients receiving hydroxychloroquine and in 84 of 906 receiving its control (rate ratio, 1.19; 95% CI, 0.89 to 1.59; P = 0.23), in 148 of 1399 patients receiving lopinavir and in 146 of 1372 receiving its control (rate ratio, 1.00; 95% CI, 0.79 to 1.25; P = 0.97), and in 243 of 2050 patients receiving interferon and in 216 of 2050 receiving its control (rate ratio, 1.16; 95% CI, 0.96 to 1.39; P = 0.11). No drug definitely reduced mortality, overall or in any subgroup, or reduced initiation of ventilation or hospitalization duration.

Conclusions: These remdesivir, hydroxychloroquine, lopinavir, and interferon regimens had little or no effect on hospitalized patients with Covid-19, as indicated by overall mortality, initiation of ventilation, and duration of hospital stay. (Funded by the World Health Organization; ISRCTN Registry number, ISRCTN83971151; ClinicalTrials.gov number, NCT04315948.).
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http://dx.doi.org/10.1056/NEJMoa2023184DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7727327PMC
February 2021

Investigating and dealing with publication bias and other reporting biases in meta-analyses of health research: A review.

Res Synth Methods 2020 Nov 9. Epub 2020 Nov 9.

Institute for Social and Preventive Medicine, University of Bern, Bern, Switzerland.

A P value, or the magnitude or direction of results can influence decisions about whether, when, and how research findings are disseminated. Regardless of whether an entire study or a particular study result is unavailable because investigators considered the results to be unfavorable, bias in a meta-analysis may occur when available results differ systematically from missing results. In this article, we summarize the empirical evidence for various reporting biases that lead to study results being unavailable for inclusion in systematic reviews, with a focus on health research. These biases include publication bias and selective nonreporting bias. We describe processes that systematic reviewers can use to minimize the risk of bias due to missing results in meta-analyses of health research, such as comprehensive searches and prospective approaches to meta-analysis. We also outline methods that have been designed for assessing risk of bias due to missing results in meta-analyses of health research, including using tools to assess selective nonreporting of results, ascertaining qualitative signals that suggest not all studies were identified, and generating funnel plots to identify small-study effects, one cause of which is reporting bias. HIGHLIGHTS: Bias in a meta-analysis may occur when available results differ systematically from missing results. Several different tools, plots, and statistical methods have been designed for assessing risk of bias due to missing results in meta-analyses. These include comparison of prespecified analysis plans with completed reports to detect selective nonreporting of results, consideration of qualitative signals that suggest not all studies were identified, and the use of funnel plots to identify small-study effects, for which reporting bias is one of several causes. Information from approaches such as funnel plots and selection models is more difficult to interpret than from less subjective approaches such as detection of incompletely reported results in studies for which prespecified analysis plans were available.
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http://dx.doi.org/10.1002/jrsm.1468DOI Listing
November 2020

Health System-Based Unhealthy Alcohol Use Screening and Treatment Comparing Demographically Matched Participants With and Without HIV.

Alcohol Clin Exp Res 2020 12 10;44(12):2545-2554. Epub 2020 Nov 10.

From the, Division of Research, (MJS, TL-H, NH, ANA, SEA, JOL, TR, CMW, SAS, DDS), Kaiser Permanente Northern California (KPNC), Oakland, California.

Background: Unhealthy alcohol use among persons living with HIV (PLWH) is linked to significant morbidity, and use of alcohol services may differ by HIV status. Our objective was to compare unhealthy alcohol use screening and treatment by HIV status in primary care.

Methods: Cohort study of adult (≥18 years) PLWH and HIV-uninfected participants frequency matched 20:1 to PLWH by age, sex, and race/ethnicity who were enrolled in a large integrated healthcare system in the United States, with information ascertained from an electronic health record. Outcomes included unhealthy alcohol screening, prevalence, provider-delivered brief interventions, and addiction specialty care visits. Other predictors included age, sex, race/ethnicity, neighborhood deprivation index, depression, smoking, substance use disorders, Charlson comorbidity index, prior outpatient visits, insurance type, and medical facility. Cox proportional hazards models were used to compute hazard ratios (HR) for the outcomes of time to unhealthy alcohol use screening and time to first addiction specialty visit. Poisson regression with robust standard errors was used to compute prevalence ratios (PR) for other outcomes.

Results: 11,235 PLWH and 227,320 HIV-uninfected participants were included. By 4.5 years after baseline, most participants were screened for unhealthy alcohol use (85% of PLWH and 93% of HIV-uninfected), but with a lower rate among PLWH (adjusted HR 0.84, 95% CI 0.82 to 0.85). PLWH were less likely, compared with HIV-uninfected participants, to report unhealthy drinking among those screened (adjusted PR 0.74, 95% CI 0.69 to 0.79), and among those who screened positive, less likely to receive brief interventions (adjusted PR 0.82, 95% CI 0.75 to 0.90), but more likely (adjusted HR 1.7, 95% CI 1.2 to 2.4) to have an addiction specialty visit within 1 year.

Conclusions: Unhealthy alcohol use was lower in PLWH, but the treatment approach by HIV status differed. PLWH reporting unhealthy alcohol use received less brief interventions and more addiction specialty care than HIV-uninfected participants.
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http://dx.doi.org/10.1111/acer.14481DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7725961PMC
December 2020

Monitoring indirect impact of COVID-19 pandemic on services for cardiovascular diseases in the UK.

Heart 2020 12 5;106(24):1890-1897. Epub 2020 Oct 5.

University Hospitals Bristol and Weston NHS Foundation Trust, Bristol, UK.

Objective: To monitor hospital activity for presentation, diagnosis and treatment of cardiovascular diseases during the COVID-19) pandemic to inform on indirect effects.

Methods: Retrospective serial cross-sectional study in nine UK hospitals using hospital activity data from 28 October 2019 (pre-COVID-19) to 10 May 2020 (pre-easing of lockdown) and for the same weeks during 2018-2019. We analysed aggregate data for selected cardiovascular diseases before and during the epidemic. We produced an online visualisation tool to enable near real-time monitoring of trends.

Results: Across nine hospitals, total admissions and emergency department (ED) attendances decreased after lockdown (23 March 2020) by 57.9% (57.1%-58.6%) and 52.9% (52.2%-53.5%), respectively, compared with the previous year. Activity for cardiac, cerebrovascular and other vascular conditions started to decline 1-2 weeks before lockdown and fell by 31%-88% after lockdown, with the greatest reductions observed for coronary artery bypass grafts, carotid endarterectomy, aortic aneurysm repair and peripheral arterial disease procedures. Compared with before the first UK COVID-19 (31 January 2020), activity declined across diseases and specialties between the first case and lockdown (total ED attendances relative reduction (RR) 0.94, 0.93-0.95; total hospital admissions RR 0.96, 0.95-0.97) and after lockdown (attendances RR 0.63, 0.62-0.64; admissions RR 0.59, 0.57-0.60). There was limited recovery towards usual levels of some activities from mid-April 2020.

Conclusions: Substantial reductions in total and cardiovascular activities are likely to contribute to a major burden of indirect effects of the pandemic, suggesting they should be monitored and mitigated urgently.
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http://dx.doi.org/10.1136/heartjnl-2020-317870DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7536637PMC
December 2020

Association Between Administration of Systemic Corticosteroids and Mortality Among Critically Ill Patients With COVID-19: A Meta-analysis.

JAMA 2020 10;324(13):1330-1341

Li Ka Shing Knowledge Institute, St Michael's Hospital, University of Toronto, Toronto, Ontario, Canada.

Importance: Effective therapies for patients with coronavirus disease 2019 (COVID-19) are needed, and clinical trial data have demonstrated that low-dose dexamethasone reduced mortality in hospitalized patients with COVID-19 who required respiratory support.

Objective: To estimate the association between administration of corticosteroids compared with usual care or placebo and 28-day all-cause mortality.

Design, Setting, And Participants: Prospective meta-analysis that pooled data from 7 randomized clinical trials that evaluated the efficacy of corticosteroids in 1703 critically ill patients with COVID-19. The trials were conducted in 12 countries from February 26, 2020, to June 9, 2020, and the date of final follow-up was July 6, 2020. Pooled data were aggregated from the individual trials, overall, and in predefined subgroups. Risk of bias was assessed using the Cochrane Risk of Bias Assessment Tool. Inconsistency among trial results was assessed using the I2 statistic. The primary analysis was an inverse variance-weighted fixed-effect meta-analysis of overall mortality, with the association between the intervention and mortality quantified using odds ratios (ORs). Random-effects meta-analyses also were conducted (with the Paule-Mandel estimate of heterogeneity and the Hartung-Knapp adjustment) and an inverse variance-weighted fixed-effect analysis using risk ratios.

Exposures: Patients had been randomized to receive systemic dexamethasone, hydrocortisone, or methylprednisolone (678 patients) or to receive usual care or placebo (1025 patients).

Main Outcomes And Measures: The primary outcome measure was all-cause mortality at 28 days after randomization. A secondary outcome was investigator-defined serious adverse events.

Results: A total of 1703 patients (median age, 60 years [interquartile range, 52-68 years]; 488 [29%] women) were included in the analysis. Risk of bias was assessed as "low" for 6 of the 7 mortality results and as "some concerns" in 1 trial because of the randomization method. Five trials reported mortality at 28 days, 1 trial at 21 days, and 1 trial at 30 days. There were 222 deaths among the 678 patients randomized to corticosteroids and 425 deaths among the 1025 patients randomized to usual care or placebo (summary OR, 0.66 [95% CI, 0.53-0.82]; P < .001 based on a fixed-effect meta-analysis). There was little inconsistency between the trial results (I2 = 15.6%; P = .31 for heterogeneity) and the summary OR was 0.70 (95% CI, 0.48-1.01; P = .053) based on the random-effects meta-analysis. The fixed-effect summary OR for the association with mortality was 0.64 (95% CI, 0.50-0.82; P < .001) for dexamethasone compared with usual care or placebo (3 trials, 1282 patients, and 527 deaths), the OR was 0.69 (95% CI, 0.43-1.12; P = .13) for hydrocortisone (3 trials, 374 patients, and 94 deaths), and the OR was 0.91 (95% CI, 0.29-2.87; P = .87) for methylprednisolone (1 trial, 47 patients, and 26 deaths). Among the 6 trials that reported serious adverse events, 64 events occurred among 354 patients randomized to corticosteroids and 80 events occurred among 342 patients randomized to usual care or placebo.

Conclusions And Relevance: In this prospective meta-analysis of clinical trials of critically ill patients with COVID-19, administration of systemic corticosteroids, compared with usual care or placebo, was associated with lower 28-day all-cause mortality.
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http://dx.doi.org/10.1001/jama.2020.17023DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7489434PMC
October 2020

Invasive versus non-invasive management of older patients with non-ST elevation myocardial infarction (SENIOR-NSTEMI): a cohort study based on routine clinical data.

Lancet 2020 08;396(10251):623-634

National Institute for Health Research Imperial Biomedical Research Centre, Imperial College London and Imperial College Healthcare NHS Trust, London, UK. Electronic address:

Background: Previous trials suggest lower long-term risk of mortality after invasive rather than non-invasive management of patients with non-ST elevation myocardial infarction (NSTEMI), but the trials excluded very elderly patients. We aimed to estimate the effect of invasive versus non-invasive management within 3 days of peak troponin concentration on the survival of patients aged 80 years or older with NSTEMI.

Methods: Routine clinical data for this study were obtained from five collaborating hospitals hosting NIHR Biomedical Research Centres in the UK (all tertiary centres with emergency departments). Eligible patients were 80 years old or older when they underwent troponin measurements and were diagnosed with NSTEMI between 2010 (2008 for University College Hospital) and 2017. Propensity scores (patients' estimated probability of receiving invasive management) based on pretreatment variables were derived using logistic regression; patients with high probabilities of non-invasive or invasive management were excluded. Patients who died within 3 days of peak troponin concentration without receiving invasive management were assigned to the invasive or non-invasive management groups based on their propensity scores, to mitigate immortal time bias. We estimated mortality hazard ratios comparing invasive with non-invasive management, and compared the rate of hospital admissions for heart failure.

Findings: Of the 1976 patients with NSTEMI, 101 died within 3 days of their peak troponin concentration and 375 were excluded because of extreme propensity scores. The remaining 1500 patients had a median age of 86 (IQR 82-89) years of whom (845 [56%] received non-invasive management. During median follow-up of 3·0 (IQR 1·2-4·8) years, 613 (41%) patients died. The adjusted cumulative 5-year mortality was 36% in the invasive management group and 55% in the non-invasive management group (adjusted hazard ratio 0·68, 95% CI 0·55-0·84). Invasive management was associated with lower incidence of hospital admissions for heart failure (adjusted rate ratio compared with non-invasive management 0·67, 95% CI 0·48-0·93).

Interpretation: The survival advantage of invasive compared with non-invasive management appears to extend to patients with NSTEMI who are aged 80 years or older.

Funding: NIHR Imperial Biomedical Research Centre, as part of the NIHR Health Informatics Collaborative.
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http://dx.doi.org/10.1016/S0140-6736(20)30930-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7456783PMC
August 2020

Corticosteroid therapy for critically ill patients with COVID-19: A structured summary of a study protocol for a prospective meta-analysis of randomized trials.

Trials 2020 Aug 24;21(1):734. Epub 2020 Aug 24.

Li Ka Shing Knowledge Institute, St. Michael's Hospital, University of Toronto, Toronto, Canada.

Objectives: Primary objective: To estimate the effect of corticosteroids compared with usual care or placebo on mortality up to 28 days after randomization. Secondary objectives: To examine whether the effect of corticosteroids compared with usual care or placebo on mortality up to 28 days after randomization varies between subgroups related to treatment characteristics, disease severity at the time of randomization, patient characteristics, or risk of bias. To examine the effect of corticosteroids compared with usual care or placebo on serious adverse events.

Study Design: Prospective meta-analysis of randomized controlled trials. Both placebo-controlled and open-label trials are eligible.

Participants: Hospitalised, critically ill patients with suspected or confirmed COVID-19.

Intervention And Comparator: Intervention groups will have received therapeutic doses of a steroid (dexamethasone, hydrocortisone or methylprednisolone) with IV or oral administration immediately after randomization. The comparator groups will have received standard of care or usual care or placebo.

Main Outcome: All-cause mortality up to 28 days after randomization.

Search Methods: Systematic searching of clinicaltrials.gov , EudraCT, the WHO ISRCTN registry, and the Chinese clinical trials registry. Additionally, research and WHO networks will be asked for relevant trials.

Risk Of Bias Assessments: These will be based on the Cochrane RoB 2 tool, and will use structured information provided by the trial investigators on a form designed for this prospective meta-analysis. We will use GRADE to assess the certainty of the evidence.

Statistical Analyses: Trial investigators will provide data on the numbers of participants who did and did not experience each outcome according to intervention group, overall and in specified subgroups. We will conduct fixed-effect (primary analysis) and random-effects (Paule-Mandel estimate of heterogeneity and Hartung-Knapp adjustment) meta-analyses. We will quantify inconsistency in effects between trials using I statistics. Evidence for subgroup effects will be quantified by ratios of odds ratios comparing effects in the subgroups, and corresponding interaction p-values. Comparisons between subgroups defined by trial characteristics will be made using random-effects meta-regression. Comparisons between subgroups defined by patient characteristics will be made by estimating trial-specific ratios of odds ratios comparing intervention effects between subgroups then combining these using random-effects meta-analysis. Steroid interventions will be classified as high or low dose according to whether the dose is greater or less than or equal to 400 mg hydrocortisone per day or equivalent. We will use network meta-analysis methods to make comparisons between the effects of high and low dose steroid interventions (because one trial randomized participants to both low and high dose steroid arms).

Prospero Registration Number: CRD42020197242 FULL PROTOCOL: The full protocol for this prospective meta-analysis is attached as an additional file, accessible from the Trials website (Additional file 1). To expedite dissemination of this material, the familiar formatting has been eliminated; this Letter serves as a summary of the key elements of the full protocol for the systematic review.
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http://dx.doi.org/10.1186/s13063-020-04641-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7443535PMC
August 2020

The median and the mode as robust meta-analysis estimators in the presence of small-study effects and outliers.

Res Synth Methods 2020 May 10;11(3):397-412. Epub 2020 Mar 10.

MRC Integrative Epidemiology Unit, University of Bristol, Bristol, UK.

Meta-analyses based on systematic literature reviews are commonly used to obtain a quantitative summary of the available evidence on a given topic. However, the reliability of any meta-analysis is constrained by that of its constituent studies. One major limitation is the possibility of small-study effects, when estimates from smaller and larger studies differ systematically. Small-study effects may result from reporting biases (ie, publication bias), from inadequacies of the included studies that are related to study size, or from reasons unrelated to bias. We propose two estimators based on the median and mode to increase the reliability of findings in a meta-analysis by mitigating the influence of small-study effects. By re-examining data from published meta-analyses and by conducting a simulation study, we show that these estimators offer robustness to a range of plausible bias mechanisms, without making explicit modelling assumptions. They are also robust to outlying studies without explicitly removing such studies from the analysis. When meta-analyses are suspected to be at risk of bias because of small-study effects, we recommend reporting the mean, median and modal pooled estimates.
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http://dx.doi.org/10.1002/jrsm.1402DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7359861PMC
May 2020

Cause-specific mortality after diagnosis of cancer among HIV-positive patients: A collaborative analysis of cohort studies.

Int J Cancer 2020 06 12;146(11):3134-3146. Epub 2020 Mar 12.

Population Health Sciences, University of Bristol, Bristol, United Kingdom.

People living with HIV (PLHIV) are more likely than the general population to develop AIDS-defining malignancies (ADMs) and several non-ADMs (NADMs). Information is lacking on survival outcomes and cause-specific mortality after cancer diagnosis among PLHIV. We investigated causes of death within 5 years of cancer diagnosis in PLHIV enrolled in European and North American HIV cohorts starting antiretroviral therapy (ART) 1996-2015, aged ≥16 years, and subsequently diagnosed with cancer. Cancers were grouped: ADMs, viral NADMs and nonviral NADMs. We calculated cause-specific mortality rates (MR) after diagnosis of specific cancers and compared 5-year survival with the UK and France general populations. Among 83,856 PLHIV there were 4,436 cancer diagnoses. Of 603 deaths after ADM diagnosis, 292 (48%) were due to an ADM. There were 467/847 (55%) and 74/189 (39%) deaths that were due to an NADM after nonviral and viral NADM diagnoses, respectively. MR were higher for diagnoses between 1996 and 2005 versus 2006-2015: ADMs 102 (95% CI 92-113) per 1,000 years versus 88 (78-100), viral NADMs 134 (106-169) versus 111 (93-133) and nonviral NADMs 264 (232-300) versus 226 (206-248). Estimated 5-year survival for PLHIV diagnosed with liver (29% [19-39%]), lung (18% [13-23%]) and cervical (75% [63-84%]) cancer was similar to general populations. Survival after Hodgkin's lymphoma diagnosis was lower in PLHIV (75% [67-81%]). Among ART-treated PLHIV diagnosed with cancer, MR and causes of death varied by cancer type, with mortality highest for liver and lung cancers. Deaths within 5 years of NADM diagnoses were more likely to be from cancer than AIDS.
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http://dx.doi.org/10.1002/ijc.32895DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7187452PMC
June 2020

Impact of blinding on estimated treatment effects in randomised clinical trials: meta-epidemiological study.

BMJ 2020 01 21;368:l6802. Epub 2020 Jan 21.

Centre for Evidence-Based Medicine Odense (CEBMO), Odense University Hospital, Kløvervænget 10, DK-5000 Odense C, Denmark.

Objectives: To study the impact of blinding on estimated treatment effects, and their variation between trials; differentiating between blinding of patients, healthcare providers, and observers; detection bias and performance bias; and types of outcome (the MetaBLIND study).

Design: Meta-epidemiological study.

Data Source: Cochrane Database of Systematic Reviews (2013-14).

Eligibility Criteria For Selecting Studies: Meta-analyses with both blinded and non-blinded trials on any topic.

Review Methods: Blinding status was retrieved from trial publications and authors, and results retrieved automatically from the Cochrane Database of Systematic Reviews. Bayesian hierarchical models estimated the average ratio of odds ratios (ROR), and estimated the increases in heterogeneity between trials, for non-blinded trials (or of unclear status) versus blinded trials. Secondary analyses adjusted for adequacy of concealment of allocation, attrition, and trial size, and explored the association between outcome subjectivity (high, moderate, low) and average bias. An ROR lower than 1 indicated exaggerated effect estimates in trials without blinding.

Results: The study included 142 meta-analyses (1153 trials). The ROR for lack of blinding of patients was 0.91 (95% credible interval 0.61 to 1.34) in 18 meta-analyses with patient reported outcomes, and 0.98 (0.69 to 1.39) in 14 meta-analyses with outcomes reported by blinded observers. The ROR for lack of blinding of healthcare providers was 1.01 (0.84 to 1.19) in 29 meta-analyses with healthcare provider decision outcomes (eg, readmissions), and 0.97 (0.64 to 1.45) in 13 meta-analyses with outcomes reported by blinded patients or observers. The ROR for lack of blinding of observers was 1.01 (0.86 to 1.18) in 46 meta-analyses with subjective observer reported outcomes, with no clear impact of degree of subjectivity. Information was insufficient to determine whether lack of blinding was associated with increased heterogeneity between trials. The ROR for trials not reported as double blind versus those that were double blind was 1.02 (0.90 to 1.13) in 74 meta-analyses.

Conclusion: No evidence was found for an average difference in estimated treatment effect between trials with and without blinded patients, healthcare providers, or outcome assessors. These results could reflect that blinding is less important than often believed or meta-epidemiological study limitations, such as residual confounding or imprecision. At this stage, replication of this study is suggested and blinding should remain a methodological safeguard in trials.
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http://dx.doi.org/10.1136/bmj.l6802DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7190062PMC
January 2020

Parameter estimates for trends and patterns of excess mortality among persons on antiretroviral therapy in high-income European settings.

AIDS 2019 12;33 Suppl 3:S271-S281

aPopulation Health Sciences, University of Bristol, Bristol, UK bStichting HIV Monitoring, Amsterdam, The Netherlands cAvenir Health, Glastonbury, Connecticut, USA dDepartment of Internal Medicine, Antoine Béclère Hospital, Clamart eUniversity of Paris Saclay, Paris-Sud University, UVSQ fCESP INSERM U1018, Le Kremlin-Bicêtre gSorbonne Université, INSERM, Institut Pierre Louis d'épidemiologie et de Santé Publique (IPLESP), Unité de Biostatistique et d'épidémiologie Groupe hospitalier Cochin Broca Hôtel-Dieu, Assistance Publique Hôpitaux de Paris (AP-HP), and Université Paris Descartes, Sorbonne Paris Cité, Paris hUniversity of Bordeaux, ISPED, INSERM U1219 and CHU de Bordeaux, Bordeaux, France iHospital General Universitario Gregorio Marañón, Instituto de Investigación Sanitaria Gregorio Marañón (IiSGM), Madrid, Spain jFirst Department of Internal Medicine, University of Cologne, Cologne, Germany kCEEISCAT/Agència de Salut Pública de Catalunya, Campus Can Ruti and CIBERESP, Badalona, Catalonia, Spain lClinic of Infectious and Tropical Diseases, Department of Health Sciences, ASST Santi Paolo e Carlo, University of Milan, Milan, Italy mService of Infectious Diseases, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland nNational Epidemiology Center, Carlos III Health Institute, Madrid, Spain and National Plan on AIDS, Ministry of Health, Madrid, Spain oInnsbruck Medical University, Austria pDivision of Infectious Diseases, University of Calgary, Calgary, Canada qDepartment of Infectious Diseases, Copenhagen University Hospital, Rigshospitalet, Denmark.

Introduction: HIV cohort data from high-income European countries were compared with the UNAIDS Spectrum modelling parameters for these same countries to validate mortality rates and excess mortality estimates for people living with HIV (PLHIV) on antiretroviral therapy (ART).

Methods: Data from 2000 to 2015 were analysed from the Antiretroviral Therapy Cohort Collaboration (ART-CC) for Austria, Denmark, France, Italy, the Netherlands, Spain, and Switzerland. Flexible parametric models were used to compare all-cause mortality rates in the ART-CC and Spectrum. The percentage of AIDS-related deaths and excess mortality (both are the same within Spectrum) were compared, with excess mortality defined as that in excess of the general population mortality.

Results: Analyses included 94 026 PLHIV with 585 784 person-years of follow-up, from which there were 5515 deaths. All-cause annual mortality rates in Spectrum for 2000-2003 were 0.0121, reducing to 0.0078 in 2012-2015, whilst the ART-CC's corresponding annual mortality rates were 0.0151 [95% confidence interval (95% CI): 0.0130-0.0171] reducing to 0.0049 (95% CI: 0.0039-0.0060). The percentage of AIDS-related deaths in Spectrum was 74.7% in 2000-2003, dropping to 43.6% in 2012-2015. In the ART-CC, AIDS-related mortality constitutes 45.3% (95% CI: 38.4-52.9%) of mortality in 2000-2003 and 26.7% (95% CI: 19-46%) between 2012 and 2015. Excess mortality in the ART-CC was broadly similar to the Spectrum estimates, dropping from 75.3% (95% CI: 60.3-95.2%) in 2000-2003 to 30.7% (95% CI: 25.5-63.7%) in 2012-2015.

Conclusion: All-cause mortality assumptions for PLHIV on ART in high-income European settings should be adjusted in Spectrum to be higher in 2000-2003 and decline more quickly to levels currently captured for recent years.
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http://dx.doi.org/10.1097/QAD.0000000000002387DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6919232PMC
December 2019

Design characteristics, risk of bias, and reporting of randomised controlled trials supporting approvals of cancer drugs by European Medicines Agency, 2014-16: cross sectional analysis.

BMJ 2019 09 18;366:l5221. Epub 2019 Sep 18.

Cancer Research Institute, Queen's University at Kingston, Kingston, Ontario, Canada.

Objective: To examine the design characteristics, risk of bias, and reporting adequacy of pivotal randomised controlled trials of cancer drugs approved by the European Medicines Agency (EMA).

Design: Cross sectional analysis.

Setting: European regulatory documents, clinical trial registry records, protocols, journal publications, and supplementary appendices.

Eligibility Criteria: Pivotal randomised controlled trials of new cancer drugs approved by the EMA between 2014 and 2016.

Main Outcome Measures: Study design characteristics (randomisation, comparators, and endpoints); risk of bias using the revised Cochrane tool (bias arising from the randomisation process, deviations from intended interventions, missing outcome data, measurement of the outcome, and selection of the reported result); and reporting adequacy (completeness and consistency of information in trial protocols, publications, supplementary appendices, clinical trial registry records, and regulatory documents).

Results: Between 2014 and 2016, the EMA approved 32 new cancer drugs on the basis of 54 pivotal studies. Of these, 41 (76%) were randomised controlled trials and 13 (24%) were either non-randomised studies or single arm studies. 39/41 randomised controlled trials had available publications and were included in our study. Only 10 randomised controlled trials (26%) measured overall survival as either a primary or coprimary endpoint, with the remaining trials evaluating surrogate measures such as progression free survival and response rates. Overall, 19 randomised controlled trials (49%) were judged to be at high risk of bias for their primary outcome. Concerns about missing outcome data (n=10) and measurement of the outcome (n=7) were the most common domains leading to high risk of bias judgments. Fewer randomised controlled trials that evaluated overall survival as the primary endpoint were at high risk of bias than those that evaluated surrogate efficacy endpoints (2/10 (20%) 16/29 (55%), respectively). When information available in regulatory documents and the scientific literature was considered separately, overall risk of bias judgments differed for eight randomised controlled trials (21%), which reflects reporting inadequacies in both sources of information. Regulators identified additional deficits beyond the domains captured in risk of bias assessments for 10 drugs (31%). These deficits included magnitude of clinical benefit, inappropriate comparators, and non-preferred study endpoints, which were not disclosed as limitations in scientific publications.

Conclusions: Most pivotal studies forming the basis of EMA approval of new cancer drugs between 2014 and 2016 were randomised controlled trials. However, almost half of these were judged to be at high risk of bias based on their design, conduct, or analysis, some of which might be unavoidable because of the complexity of cancer trials. Regulatory documents and the scientific literature had gaps in their reporting. Journal publications did not acknowledge the key limitations of the available evidence identified in regulatory documents.
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http://dx.doi.org/10.1136/bmj.l5221DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6749182PMC
September 2019

Directly Acting Oral Anticoagulants for the Prevention of Stroke in Atrial Fibrillation in England and Wales: Cost-Effectiveness Model and Value of Information Analysis.

MDM Policy Pract 2019 Jul-Dec;4(2):2381468319866828. Epub 2019 Aug 17.

Bristol Medical School, University of Bristol, Bristol, UK.

Determine the optimal, licensed, first-line anticoagulant for prevention of ischemic stroke in patients with non-valvular atrial fibrillation (AF) in England and Wales from the UK National Health Service (NHS) perspective and estimate value to decision making of further research. We developed a cost-effectiveness model to compare warfarin (international normalized ratio target range 2-3) with directly acting (or non-vitamin K antagonist) oral anticoagulants (DOACs) apixaban 5 mg, dabigatran 150 mg, edoxaban 60 mg, and rivaroxaban 20 mg, over 30 years post treatment initiation. In addition to death, the 17-state Markov model included the events stroke, bleed, myocardial infarction, and intracranial hemorrhage. Input parameters were informed by systematic literature reviews and network meta-analysis. Expected value of perfect information (EVPI) and expected value of partial perfect information (EVPPI) were estimated to provide an upper bound on value of further research. At willingness-to-pay threshold £20,000, all DOACs have positive expected incremental net benefit compared to warfarin, suggesting they are likely cost-effective. Apixaban has highest expected incremental net benefit (£7533), followed by dabigatran (£6365), rivaroxaban (£5279), and edoxaban (£5212). There was considerable uncertainty as to the optimal DOAC, with the probability apixaban has highest net benefit only 60%. Total estimated population EVPI was £17.94 million (17.85 million, 18.03 million), with relative effect between apixaban versus dabigatran making the largest contribution with EVPPI of £7.95 million (7.66 million, 8.24 million). At willingness-to-pay threshold £20,000, all DOACs have higher expected net benefit than warfarin but there is considerable uncertainty between the DOACs. Apixaban had the highest expected net benefit and greatest probability of having highest net benefit, but there is considerable uncertainty between DOACs. A head-to-head apixaban versus dabigatran trial may be of value.
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http://dx.doi.org/10.1177/2381468319866828DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6699015PMC
August 2019

Use of machine learning to analyse routinely collected intensive care unit data: a systematic review.

Crit Care 2019 Aug 22;23(1):284. Epub 2019 Aug 22.

NIHR Bristol Biomedical Research Centre, University of Bristol, Bristol, UK.

Background: Intensive care units (ICUs) face financial, bed management, and staffing constraints. Detailed data covering all aspects of patients' journeys into and through intensive care are now collected and stored in electronic health records: machine learning has been used to analyse such data in order to provide decision support to clinicians.

Methods: Systematic review of the applications of machine learning to routinely collected ICU data. Web of Science and MEDLINE databases were searched to identify candidate articles: those on image processing were excluded. The study aim, the type of machine learning used, the size of dataset analysed, whether and how the model was validated, and measures of predictive accuracy were extracted.

Results: Of 2450 papers identified, 258 fulfilled eligibility criteria. The most common study aims were predicting complications (77 papers [29.8% of studies]), predicting mortality (70 [27.1%]), improving prognostic models (43 [16.7%]), and classifying sub-populations (29 [11.2%]). Median sample size was 488 (IQR 108-4099): 41 studies analysed data on > 10,000 patients. Analyses focused on 169 (65.5%) papers that used machine learning to predict complications, mortality, length of stay, or improvement of health. Predictions were validated in 161 (95.2%) of these studies: the area under the ROC curve (AUC) was reported by 97 (60.2%) but only 10 (6.2%) validated predictions using independent data. The median AUC was 0.83 in studies of 1000-10,000 patients, rising to 0.94 in studies of > 100,000 patients. The most common machine learning methods were neural networks (72 studies [42.6%]), support vector machines (40 [23.7%]), and classification/decision trees (34 [20.1%]). Since 2015 (125 studies [48.4%]), the most common methods were support vector machines (37 studies [29.6%]) and random forests (29 [23.2%]).

Conclusions: The rate of publication of studies using machine learning to analyse routinely collected ICU data is increasing rapidly. The sample sizes used in many published studies are too small to exploit the potential of these methods. Methodological and reporting guidelines are needed, particularly with regard to the choice of method and validation of predictions, to increase confidence in reported findings and aid in translating findings towards routine use in clinical practice.
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http://dx.doi.org/10.1186/s13054-019-2564-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6704673PMC
August 2019

Letter re: stratification of meta-analyses based on risk of bias is appropriate and does not induce selection bias.

J Clin Epidemiol 2019 11 6;115:175-176. Epub 2019 Jun 6.

Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, UK; NIHR Bristol Biomedical Research Centre, Bristol, UK.

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http://dx.doi.org/10.1016/j.jclinepi.2019.06.003DOI Listing
November 2019

Comprehensive ascertainment of bleeding in patients prescribed different combinations of dual antiplatelet therapy (DAPT) and triple therapy (TT) in the UK: study protocol for three population-based cohort studies emulating 'target trials' (the ADAPTT Study).

BMJ Open 2019 06 4;9(6):e029388. Epub 2019 Jun 4.

Clinical Trials and Evaluation Unit, Bristol Trials Centre, University of Bristol, Bristol, UK.

Introduction: 'Real world' bleeding in patients exposed to different regimens of dual antiplatelet therapy (DAPT) and triple therapy (TT, DAPT plus an anticoagulant) have a clinical and economic impact but have not been previously quantified.

Methods And Analysis: We will use linked Clinical Practice Research Datalink (CPRD) and Hospital Episode Statistics (HES) data to assemble populations eligible for three 'target trials' in patient groups: percutaneous coronary intervention (PCI); coronary artery bypass grafting (CABG); conservatively managed (medication only) acute coronary syndrome (ACS). Patients ≥18 years old will be eligible if, in CPRD records, they have: ≥1 year of data before the index event; no prescription for DAPT or anticoagulants in the preceding 3 months; a prescription for aspirin or DAPT within 2 months after discharge from the index event. The primary outcome will be any bleeding event (CPRD or HES) up to 12 months after the index event. We will estimate adjusted HR for time to first bleeding event comparing: aspirin and clopidogrel (reference) versus aspirin and prasugrel or aspirin and ticagrelor after PCI; and aspirin (reference) versus aspirin and clopidogrel after CABG and ACS. We will describe rates of bleeding in patients prescribed TT (DAPT plus an anticoagulant). Potential confounders will be identified systematically using literature review, semistructured interviews with clinicians and a short survey of clinicians. We will conduct sensitivity analyses addressing the robustness of results to the study's main limitation-that we will not be able to identify the intervention group for patients whose bleeding event occurs before a DAPT prescription in CPRD.

Ethics And Dissemination: This protocol was approved by the Independent Scientific Advisory Committee for the UK Medicines and Healthcare Products Regulatory Agency Database Research (protocol 16_126R) and the South West Cornwall and Plymouth Research Ethics Committee (17/SW/0092). The findings will be presented in peer-reviewed journals, lay summaries and briefing papers to commissioners/other stakeholders.

Trial Registration Number: 76607611; Pre-results.
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http://dx.doi.org/10.1136/bmjopen-2019-029388DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6561407PMC
June 2019

Selection bias introduced by informative censoring in studies examining effects of vaccination in infancy.

Int J Epidemiol 2019 12;48(6):2001-2009

Department of Population Health Sciences, Bristol Medical School, University of Bristol, UK.

Background: Many studies have examined 'non-specific' vaccine effects on infant mortality: attention has been particularly drawn to diphtheria-tetanus-pertussis (DTP) vaccine, which has been proposed to be associated with an increased mortality risk. Both right and left censoring are common in such studies.

Methods: We conducted simulation studies examining right censoring (at measles vaccination) and left censoring (by excluding early follow-up) in a variety of scenarios in which confounding was and was not present. We estimated both unadjusted and adjusted hazard ratios (HRs), averaged across simulations.

Results: We identified scenarios in which right-censoring at measles vaccination was informative and so introduced bias in the direction of a detrimental effect of DTP vaccine. In some, but not all, situations, adjusting for confounding by health status removed the bias caused by censoring. However, such adjustment will not always remove bias due to informative censoring: inverse probability weighting was required in one scenario. Bias due to left censoring arose when both health status and DTP vaccination were associated with mortality during the censored early follow-up and was in the direction of attenuating a beneficial effect of DTP on mortality. Such bias was more severe when the effect of DTP changed over time.

Conclusions: Estimates of non-specific effects of vaccines may be biased by informative right or left censoring. Authors of studies estimating such effects should consider the potential for such bias and use appropriate statistical approaches to control for it. Such approaches require measurement of prognostic factors that predict censoring.
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http://dx.doi.org/10.1093/ije/dyz092DOI Listing
December 2019

Effect Estimates in Randomized Trials and Observational Studies: Comparing Apples With Apples.

Am J Epidemiol 2019 08;188(8):1569-1577

Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, Massachusetts.

Effect estimates from randomized trials and observational studies might not be directly comparable because of differences in study design, other than randomization, and in data analysis. We propose a 3-step procedure to facilitate meaningful comparisons of effect estimates from randomized trials and observational studies: 1) harmonization of the study protocols (eligibility criteria, treatment strategies, outcome, start and end of follow-up, causal contrast) so that the studies target the same causal effect, 2) harmonization of the data analysis to estimate the causal effect, and 3) sensitivity analyses to investigate the impact of discrepancies that could not be accounted for in the harmonization process. To illustrate our approach, we compared estimates of the effect of immediate with deferred initiation of antiretroviral therapy in individuals positive for the human immunodeficiency virus from the Strategic Timing of Antiretroviral Therapy (START) randomized trial and the observational HIV-CAUSAL Collaboration.
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http://dx.doi.org/10.1093/aje/kwz100DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6670045PMC
August 2019

Accounting for missing data in statistical analyses: multiple imputation is not always the answer.

Int J Epidemiol 2019 08;48(4):1294-1304

Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, UK.

Background: Missing data are unavoidable in epidemiological research, potentially leading to bias and loss of precision. Multiple imputation (MI) is widely advocated as an improvement over complete case analysis (CCA). However, contrary to widespread belief, CCA is preferable to MI in some situations.

Methods: We provide guidance on choice of analysis when data are incomplete. Using causal diagrams to depict missingness mechanisms, we describe when CCA will not be biased by missing data and compare MI and CCA, with respect to bias and efficiency, in a range of missing data situations. We illustrate selection of an appropriate method in practice.

Results: For most regression models, CCA gives unbiased results when the chance of being a complete case does not depend on the outcome after taking the covariates into consideration, which includes situations where data are missing not at random. Consequently, there are situations in which CCA analyses are unbiased while MI analyses, assuming missing at random (MAR), are biased. By contrast MI, unlike CCA, is valid for all MAR situations and has the potential to use information contained in the incomplete cases and auxiliary variables to reduce bias and/or improve precision. For this reason, MI was preferred over CCA in our real data example.

Conclusions: Choice of method for dealing with missing data is crucial for validity of conclusions, and should be based on careful consideration of the reasons for the missing data, missing data patterns and the availability of auxiliary information.
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http://dx.doi.org/10.1093/ije/dyz032DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6693809PMC
August 2019

Albumin, white blood cell count, and body mass index improve discrimination of mortality in HIV-positive individuals.

AIDS 2019 04;33(5):903-912

VA Connecticut Health Systems, West Haven, Connecticut, USA.

Objective: Despite viral suppression and immune response on antiretroviral therapy, people with HIV infection experience excess mortality compared with uninfected individuals. The Veterans Aging Cohort Study (VACS) Index incorporates clinical biomarkers of general health with age, CD4 cell count, and HIV-1 RNA to discriminate mortality risk in a variety of HIV-positive populations. We asked whether additional biomarkers further enhance discrimination.

Design And Methods: Using patients from VACS for development and from the Antiretroviral Therapy Cohort Collaboration (ART-CC) for validation, we obtained laboratory values from a randomly selected visit from 2000 to 2014, at least 1 year after antiretroviral therapy initiation. Patients were followed for 5-year, all-cause mortality through September 2016. We fitted Cox models with established predictors and added new predictors based on model fit and Harrell's c-statistic. We converted all variables to continuous functional forms and selected the best model (VACS Index 2.0) for validation in ART-CC patients. We compared discrimination using c-statistics and Kaplan-Meier plots.

Results: Among 28 390 VACS patients and 12 109 ART-CC patients, 7293 and 722 died, respectively. Nadir CD4, CD8, and CD4 : CD8 ratio did not improve discrimination. Addition of albumin, white blood count, and BMI, improved c-statistics in VACS from 0.776 to 0.805 and in ART-CC from 0.800 to 0.831. Results were robust in all nine ART-CC cohorts, all lengths of follow-up and all subgroups.

Conclusion: VACS Index 2.0, adding albumin, white blood count, and BMI to version 1.0 and using continuous variables, provides improved discrimination and is highly transportable to external settings.
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http://dx.doi.org/10.1097/QAD.0000000000002140DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6749990PMC
April 2019

Identifying Risk of Viral Failure in Treated HIV-Infected Patients Using Different Measures of Adherence: The Antiretroviral Therapy Cohort Collaboration.

J Clin Med 2018 Oct 5;7(10). Epub 2018 Oct 5.

Population Health Sciences, Bristol Medical School, University of Bristol, Bristol BS8 2PS, UK.

Adherence to antiretroviral therapy (ART) is critical for successful treatment of Human Immunodeficiency Virus (HIV), but comparisons across settings are difficult because adherence is measured in different ways. We examined utility of different adherence measures for identification of patients at risk of viral failure (VF). Eight cohorts in the ART Cohort Collaboration contributed data from pharmacy refills or self-report questionnaires collected between 1996 and 2013 ( = 11689). For pharmacy data ( = 7156), we examined associations of percentage adherence during the 1st year of ART with VF (>500 copies/mL) at 1 year. For self-report data ( = 4533), we examined 28-day adherence with VF based on closest viral load measure within 6 months after questionnaire date. Since adherence differed markedly by measurement type, we defined different cut-off points for pharmacy (lower <45%, medium 45⁻99%, higher 100%) and self-report (lower ≤95%, medium 96⁻99%, higher 100%) data. Adjusted odds ratios (ORs) for VF in lower and medium, compared to higher adherence groups, were 23.04 (95% CI: 18.44⁻28.78) and 3.84 (3.36⁻4.39) for pharmacy data. For self-report data, they were 3.19 (2.31⁻4.40) and 1.08 (0.80⁻1.46). Both types of measure were strongly associated with VF. Although adherence measurements over longer time-frames are preferable for prediction, they are less useful for intervention.
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http://dx.doi.org/10.3390/jcm7100328DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6209956PMC
October 2018

Assessing the Credibility of Findings From Nonrandomized Studies of Interventions.

JAMA Cardiol 2018 10;3(10):905-906

Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, United Kingdom.

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http://dx.doi.org/10.1001/jamacardio.2018.2267DOI Listing
October 2018

Long terms trends in CD4+ cell counts, CD8+ cell counts, and the CD4+ :  CD8+ ratio.

AIDS 2018 06;32(10):1361-1367

Population Health Sciences, Bristol Medical School.

Objective: Model trajectories of CD4+ and CD8+ cell counts after starting combination antiretroviral therapy (ART) and use the model to predict trends in these counts and the CD4+ : CD8+ ratio.

Design: Cohort study of antiretroviral-naïve HIV-positive adults who started ART after 1997 (ART Cohort Collaboration) with more than 6 months of follow-up data.

Methods: We jointly estimated CD4+ and CD8+ cell count trends and their correlation using a bivariate random effects model, with linear splines describing their population trends, and predicted the CD4+ : CD8+ ratio trend from this model. We assessed whether CD4+ and CD8+ cell count trends and the CD4+ : CD8+ ratio trend varied according to CD4+ cell count at start of ART (baseline), and, whether these trends differed in patients with and without virological failure more than 6 months after starting ART.

Results: A total of 39 979 patients were included (median follow-up was 53 months). Among patients with baseline CD4+ cell count at least 50 cells/μl, predicted mean CD8+ cell counts continued to decrease between 3 and 15 years post-ART, partly driving increases in the predicted mean CD4+ : CD8+ ratio. During 15 years of follow-up, normalization of the predicted mean CD4+ : CD8+ ratio (to >1) was only observed among patients with baseline CD4+ cell count at least 200 cells/μl. A higher baseline CD4+ cell count predicted a shorter time to normalization.

Conclusion: Declines in CD8+ cell count and increases in CD4+ : CD8+ ratio occurred up to 15 years after starting ART. The likelihood of normalization of the CD4+ : CD8+ ratio is strongly related to baseline CD4+ cell count.
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http://dx.doi.org/10.1097/QAD.0000000000001848DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5991182PMC
June 2018

Effect of a Low-Intensity PSA-Based Screening Intervention on Prostate Cancer Mortality: The CAP Randomized Clinical Trial.

JAMA 2018 03;319(9):883-895

Nuffield Department of Surgical Sciences, University of Oxford, Oxford, England.

Importance: Prostate cancer screening remains controversial because potential mortality or quality-of-life benefits may be outweighed by harms from overdetection and overtreatment.

Objective: To evaluate the effect of a single prostate-specific antigen (PSA) screening intervention and standardized diagnostic pathway on prostate cancer-specific mortality.

Design, Setting, And Participants: The Cluster Randomized Trial of PSA Testing for Prostate Cancer (CAP) included 419 582 men aged 50 to 69 years and was conducted at 573 primary care practices across the United Kingdom. Randomization and recruitment of the practices occurred between 2001 and 2009; patient follow-up ended on March 31, 2016.

Intervention: An invitation to attend a PSA testing clinic and receive a single PSA test vs standard (unscreened) practice.

Main Outcomes And Measures: Primary outcome: prostate cancer-specific mortality at a median follow-up of 10 years. Prespecified secondary outcomes: diagnostic cancer stage and Gleason grade (range, 2-10; higher scores indicate a poorer prognosis) of prostate cancers identified, all-cause mortality, and an instrumental variable analysis estimating the causal effect of attending the PSA screening clinic.

Results: Among 415 357 randomized men (mean [SD] age, 59.0 [5.6] years), 189 386 in the intervention group and 219 439 in the control group were included in the analysis (n = 408 825; 98%). In the intervention group, 75 707 (40%) attended the PSA testing clinic and 67 313 (36%) underwent PSA testing. Of 64 436 with a valid PSA test result, 6857 (11%) had a PSA level between 3 ng/mL and 19.9 ng/mL, of whom 5850 (85%) had a prostate biopsy. After a median follow-up of 10 years, 549 (0.30 per 1000 person-years) died of prostate cancer in the intervention group vs 647 (0.31 per 1000 person-years) in the control group (rate difference, -0.013 per 1000 person-years [95% CI, -0.047 to 0.022]; rate ratio [RR], 0.96 [95% CI, 0.85 to 1.08]; P = .50). The number diagnosed with prostate cancer was higher in the intervention group (n = 8054; 4.3%) than in the control group (n = 7853; 3.6%) (RR, 1.19 [95% CI, 1.14 to 1.25]; P < .001). More prostate cancer tumors with a Gleason grade of 6 or lower were identified in the intervention group (n = 3263/189 386 [1.7%]) than in the control group (n = 2440/219 439 [1.1%]) (difference per 1000 men, 6.11 [95% CI, 5.38 to 6.84]; P < .001). In the analysis of all-cause mortality, there were 25 459 deaths in the intervention group vs 28 306 deaths in the control group (RR, 0.99 [95% CI, 0.94 to 1.03]; P = .49). In the instrumental variable analysis for prostate cancer mortality, the adherence-adjusted causal RR was 0.93 (95% CI, 0.67 to 1.29; P = .66).

Conclusions And Relevance: Among practices randomized to a single PSA screening intervention vs standard practice without screening, there was no significant difference in prostate cancer mortality after a median follow-up of 10 years but the detection of low-risk prostate cancer cases increased. Although longer-term follow-up is under way, the findings do not support single PSA testing for population-based screening.

Trial Registration: ISRCTN Identifier: ISRCTN92187251.
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http://dx.doi.org/10.1001/jama.2018.0154DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5885905PMC
March 2018

Accuracy of cystatin C for the detection of abnormal renal function in children undergoing chemotherapy for malignancy: a systematic review using individual patient data.

Support Care Cancer 2018 May 6;26(5):1635-1644. Epub 2017 Dec 6.

Centre for Reviews and Dissemination, University of York, York, YO10 5DD, UK.

Purpose: We conducted a systematic review and individual patient data (IPD) meta-analysis to examine the utility of cystatin C for evaluation of glomerular function in children with cancer.

Methods: Eligible studies evaluated the accuracy of cystatin C for detecting poor renal function in children undergoing chemotherapy. Study quality was assessed using QUADAS-2. Authors of four studies shared IPD. We calculated the correlation between log cystatin C and GFR stratified by study and measure of cystatin C. We dichotomized the reference standard at GFR 80 ml/min/1.73m and stratified cystatin C at 1 mg/l, to calculate sensitivity and specificity in each study and according to age group (0-4, 5-12, and ≥ 13 years). In sensitivity analyses, we investigated different GFR and cystatin C cut points. We used logistic regression to estimate the association of impaired renal function with log cystatin C and quantified diagnostic accuracy using the area under the ROC curve (AUC).

Results: Six studies, which used different test and reference standard thresholds, suggested that cystatin C has the potential to monitor renal function in children undergoing chemotherapy for malignancy. IPD data (504 samples, 209 children) showed that cystatin C has poor sensitivity (63%) and moderate specificity (89%), although use of a GFR cut point of < 60 ml/min/1.73m (data only available from two of the studies) estimated sensitivity to be 92% and specificity 81.3%. The AUC for the combined data set was 0.890 (95% CI 0.826, 0.951). Diagnostic accuracy appeared to decrease with age.

Conclusions: Cystatin C has better diagnostic accuracy than creatinine as a test for glomerular dysfunction in young people undergoing treatment for cancer. Diagnostic accuracy is not sufficient for it to replace current reference standards for predicting clinically relevant impairments that may alter dosing of important nephrotoxic agents.
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http://dx.doi.org/10.1007/s00520-017-4002-3DOI Listing
May 2018

Oral anticoagulants for prevention of stroke in atrial fibrillation: systematic review, network meta-analysis, and cost effectiveness analysis.

BMJ 2017 Nov 28;359:j5058. Epub 2017 Nov 28.

Faculty of Population Health Sciences, University College London, London, UK.

 To compare the efficacy, safety, and cost effectiveness of direct acting oral anticoagulants (DOACs) for patients with atrial fibrillation. Systematic review, network meta-analysis, and cost effectiveness analysis.  Medline, PreMedline, Embase, and The Cochrane Library. Published randomised trials evaluating the use of a DOAC, vitamin K antagonist, or antiplatelet drug for prevention of stroke in patients with atrial fibrillation. 23 randomised trials involving 94 656 patients were analysed: 13 compared a DOAC with warfarin dosed to achieve a target INR of 2.0-3.0. Apixaban 5 mg twice daily (odds ratio 0.79, 95% confidence interval 0.66 to 0.94), dabigatran 150 mg twice daily (0.65, 0.52 to 0.81), edoxaban 60 mg once daily (0.86, 0.74 to 1.01), and rivaroxaban 20 mg once daily (0.88, 0.74 to 1.03) reduced the risk of stroke or systemic embolism compared with warfarin. The risk of stroke or systemic embolism was higher with edoxaban 60 mg once daily (1.33, 1.02 to 1.75) and rivaroxaban 20 mg once daily (1.35, 1.03 to 1.78) than with dabigatran 150 mg twice daily. The risk of all-cause mortality was lower with all DOACs than with warfarin. Apixaban 5 mg twice daily (0.71, 0.61 to 0.81), dabigatran 110 mg twice daily (0.80, 0.69 to 0.93), edoxaban 30 mg once daily (0.46, 0.40 to 0.54), and edoxaban 60 mg once daily (0.78, 0.69 to 0.90) reduced the risk of major bleeding compared with warfarin. The risk of major bleeding was higher with dabigatran 150 mg twice daily than apixaban 5 mg twice daily (1.33, 1.09 to 1.62), rivaroxaban 20 mg twice daily than apixaban 5 mg twice daily (1.45, 1.19 to 1.78), and rivaroxaban 20 mg twice daily than edoxaban 60 mg once daily (1.31, 1.07 to 1.59). The risk of intracranial bleeding was substantially lower for most DOACs compared with warfarin, whereas the risk of gastrointestinal bleeding was higher with some DOACs than warfarin. Apixaban 5 mg twice daily was ranked the highest for most outcomes, and was cost effective compared with warfarin. The network meta-analysis informs the choice of DOACs for prevention of stroke in patients with atrial fibrillation. Several DOACs are of net benefit compared with warfarin. A trial directly comparing DOACs would overcome the need for indirect comparisons to be made through network meta-analysis. PROSPERO CRD 42013005324.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5704695PMC
http://dx.doi.org/10.1136/bmj.j5058DOI Listing
November 2017

Association Between Risk-of-Bias Assessments and Results of Randomized Trials in Cochrane Reviews: The ROBES Meta-Epidemiologic Study.

Am J Epidemiol 2018 05;187(5):1113-1122

Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, United Kingdom.

Flaws in the design of randomized trials may bias intervention effect estimates and increase between-trial heterogeneity. Empirical evidence suggests that these problems are greatest for subjectively assessed outcomes. For the Risk of Bias in Evidence Synthesis (ROBES) Study, we extracted risk-of-bias judgements (for sequence generation, allocation concealment, blinding, and incomplete data) from a large collection of meta-analyses published in the Cochrane Library (issue 4; April 2011). We categorized outcome measures as mortality, other objective outcome, or subjective outcome, and we estimated associations of bias judgements with intervention effect estimates using Bayesian hierarchical models. Among 2,443 randomized trials in 228 meta-analyses, intervention effect estimates were, on average, exaggerated in trials with high or unclear (versus low) risk-of-bias judgements for sequence generation (ratio of odds ratios (ROR) = 0.91, 95% credible interval (CrI): 0.86, 0.98), allocation concealment (ROR = 0.92, 95% CrI: 0.86, 0.98), and blinding (ROR = 0.87, 95% CrI: 0.80, 0.93). In contrast to previous work, we did not observe consistently different bias for subjective outcomes compared with mortality. However, we found an increase in between-trial heterogeneity associated with lack of blinding in meta-analyses with subjective outcomes. Inconsistency in criteria for risk-of-bias judgements applied by individual reviewers is a likely limitation of routinely collected bias assessments. Inadequate randomization and lack of blinding may lead to exaggeration of intervention effect estimates in randomized trials.
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http://dx.doi.org/10.1093/aje/kwx344DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5928453PMC
May 2018

Temporal stability of multitrigger and episodic viral wheeze in early childhood.

Eur Respir J 2017 11 2;50(5). Epub 2017 Nov 2.

Institute of Social and Preventive Medicine (ISPM), University of Bern, Bern, Switzerland.

The distinction between episodic viral wheeze (EVW) and multitrigger wheeze (MTW) is used to guide management of preschool wheeze. It has been questioned whether these phenotypes are stable over time. We examined the temporal stability of MTW and EVW in two large population-based cohorts.We classified children from the Avon Longitudinal Study of Parents and Children (n=10 970) and the Leicester Respiratory Cohorts ((LRCs), n=3263) into EVW, MTW and no wheeze at ages 2, 4 and 6 years based on parent-reported symptoms. Using multinomial regression, we estimated relative risk ratios for EVW and MTW at follow-up (no wheeze as reference category) with and without adjusting for wheeze severity.Although large proportions of children with EVW and MTW became asymptomatic, those that continued to wheeze showed a tendency to remain in the same phenotype: among children with MTW at 4 years in the LRCs, the adjusted relative risk ratio was 15.6 (95% CI 8.3-29.2) for MTW (stable phenotype) compared to 7.0 (95% CI 2.6-18.9) for EVW (phenotype switching) at 6 years. The tendency to persist was weaker for EVW and from 2-4 years. Results were similar across cohorts.This suggests that MTW, and to a lesser extent EVW, tend to persist regardless of wheeze severity.
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http://dx.doi.org/10.1183/13993003.00014-2017DOI Listing
November 2017