Publications by authors named "Erica Scher"

24 Publications

  • Page 1 of 1

Ischaemic stroke on anticoagulation therapy and early recurrence in acute cardioembolic stroke: the IAC study.

J Neurol Neurosurg Psychiatry 2021 Apr 26. Epub 2021 Apr 26.

Neuroscience Institute, Spectrum Health, Grand Rapids, Michigan, USA.

Background And Purpose: A subset of ischaemic stroke patients with atrial fibrillation (AF) have ischaemic stroke despite anticoagulation. We sought to determine the association between prestroke anticoagulant therapy and recurrent ischaemic events and symptomatic intracranial haemorrhage (sICH).

Methods: We included consecutive patients with acute ischaemic stroke and AF from the Initiation of Anticoagulation after Cardioembolic stroke (IAC) study from eight comprehensive stroke centres in the USA. We compared recurrent ischaemic events and delayed sICH risk using adjusted Cox regression analyses between patients who were prescribed anticoagulation (ACp) versus patients who were naïve to anticoagulation therapy prior to the ischaemic stroke (anticoagulation naïve).

Results: Among 2084 patients in IAC, 1518 had prior anticoagulation status recorded and were followed for 90 days. In adjusted Cox hazard models, ACp was associated with some evidence of a higher risk higher risk of 90-day recurrent ischaemic events only in the fully adjusted model (adjusted HR 1.50, 95% CI 0.99 to 2.28, p=0.058) but not increased risk of 90-day sICH (adjusted HR 1.08, 95% CI 0.46 to 2.51, p=0.862). In addition, switching anticoagulation class was not associated with reduced risk of recurrent ischaemic events (adjusted HR 0.41, 95% CI 0.12 to 1.33, p=0.136) nor sICH (adjusted HR 1.47, 95% CI 0.29 to 7.50, p=0.641).

Conclusion: AF patients with ischaemic stroke despite anticoagulation may have higher recurrent ischaemic event risk compared with anticoagulation-naïve patients. This suggests differing underlying pathomechanisms requiring different stroke prevention measures and identifying these mechanisms may improve secondary prevention strategies.
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http://dx.doi.org/10.1136/jnnp-2021-326166DOI Listing
April 2021

Treatment with Zinc is Associated with Reduced In-Hospital Mortality Among COVID-19 Patients: A Multi-Center Cohort Study.

Res Sq 2020 Oct 26. Epub 2020 Oct 26.

Zinc impairs replication of RNA viruses such as SARS-CoV-1, and may be effective against SARS-CoV-2. However, to achieve adequate intracellular zinc levels, administration with an ionophore, which increases intracellular zinc levels, may be necessary. We evaluated the impact of zinc with an ionophore (Zn+ionophore) on COVID-19 in-hospital mortality rates. A multicenter cohort study was conducted of 3,473 adult hospitalized patients with reverse-transcriptase-polymerase-chain-reaction (RT-PCR) positive SARS-CoV-2 infection admitted to four New York City hospitals between March 10 through May 20, 2020. Exclusion criteria were: death or discharge within 24h, comfort-care status, clinical trial enrollment, treatment with an IL-6 inhibitor or remdesivir. Patients who received Zn+ionophore were compared to patients who did not using multivariable time-dependent cox proportional hazards models for time to in-hospital death adjusting for confounders including age, sex, race, BMI, diabetes, week of admission, hospital location, sequential organ failure assessment (SOFA) score, intubation, acute renal failure, neurological events, treatment with corticosteroids, azithromycin or lopinavir/ritonavir and the propensity score of receiving Zn+ionophore. A sensitivity analysis was performed using a propensity score-matched cohort of patients who did or did not receive Zn+ionophore matched by age, sex and ventilator status. Among 3,473 patients (median age 64, 1947 [56%] male, 522 [15%] ventilated, 545[16%] died), 1,006 (29%) received Zn+ionophore. Zn+ionophore was associated with a 24% reduced risk of in-hospital mortality (12% of those who received Zn+ionophore died versus 17% who did not; adjusted Hazard Ratio [aHR] 0.76, 95% CI 0.60-0.96, P=0.023). More patients who received Zn+ionophore were discharged home (72% Zn+ionophore vs 67% no Zn+ionophore, P=0.003) Neither Zn nor the ionophore alone were associated with decreased mortality rates. Propensity score-matched sensitivity analysis (N=1356) validated these results (Zn+ionophore aHR for mortality 0.63, 95%CI 0.44-0.91, P=0.015). There were no significant interactions for Zn+ionophore with other COVID-19 specific medications. Zinc with an ionophore was associated with increased rates of discharge home and a 24% reduced risk of in-hospital mortality among COVID-19 patients, while neither zinc alone nor the ionophore alone reduced mortality. Further randomized trials are warranted.
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http://dx.doi.org/10.21203/rs.3.rs-94509/v1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7605567PMC
October 2020

Mild fever as a catalyst for consumption of the ischaemic penumbra despite endovascular reperfusion.

Brain Commun 2020 28;2(2):fcaa116. Epub 2020 Jul 28.

Department of Neurology, Emory University Hospital, Atlanta, GA, USA.

Cerebrovascular ischaemia is potentiated by hyperthermia, and even mild temperature elevation has proved detrimental to ischaemic brain. Infarction progression following endovascular reperfusion relates to multiple patient-specific and procedural variables; however, the potential influence of mild systemic temperature fluctuations is not fully understood. This study aims to assess the relationship between systemic temperatures in the early aftermath of acute ischaemic stroke and the loss of at-risk tissues, hypothesizing consumption of the ischaemic penumbra as a function of systemic temperatures, irrespective of reperfusion status. A cross-sectional, retrospective evaluation of a single-institution, prospectively collected endovascular therapy registry was conducted. Patients with anterior circulation, large vessel occlusion acute ischaemic stroke who underwent initial CT perfusion, and in whom at least four-hourly systemic temperatures were recorded beginning from presentation and until the time of final imaging outcome were included. Initial CT perfusion core and penumbra volumes and final MRI infarction volumes were computed. Systemic temperature indices including temperature maxima were recorded, and pre-defined temperature thresholds varying between 37°C and 38°C were examined in unadjusted and adjusted regression models which included glucose, collateral status, reperfusion status, CT perfusion-to-reperfusion delay, general anaesthesia and antipyretic exposure. The primary outcome was the relative consumption of the penumbra, reflecting normalized growth of the at-risk tissue volume ≥10%. The final study population comprised 126 acute ischaemic stroke subjects (mean 63 ± 14.5 years, 63% women). The primary outcome of penumbra consumption ≥10% occurred in 51 (40.1%) subjects. No significant differences in baseline characteristics were present between groups, with the exception of presentation glucose (118 ± 26.6 without versus 143.1 ± 61.6 with penumbra consumption,  = 0.009). Significant differences in the likelihood of penumbra consumption relating to systemic temperature maxima were observed [37°C (interquartile range 36.5 - 37.5°C) without versus 37.5°C (interquartile range 36.8 - 38.2°C) with penumbra consumption,  = 0.001]. An increased likelihood of penumbra consumption was observed for temperature maxima in unadjusted (odds ratio 3.57, 95% confidence interval 1.65 - 7.75;  = 0.001) and adjusted (odds ratio 3.06, 95% confidence interval 1.33 - 7.06;  = 0.009) regression models. Significant differences in median penumbra consumption were present at a pre-defined temperature maxima threshold of 37.5°C [4.8 ml (interquartile range 0 - 11.5 ml) versus 21.1 ml (0 - 44.7 ml) for subjects not reaching or reaching the threshold, respectively,  = 0.007]. Mild fever may promote loss of the ischaemic penumbra irrespective of reperfusion, potentially influencing successful salvage of at-risk tissue volumes following acute ischaemic stroke.
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http://dx.doi.org/10.1093/braincomms/fcaa116DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7532660PMC
July 2020

A Prospective Study of Neurologic Disorders in Hospitalized Patients With COVID-19 in New York City.

Neurology 2021 01 5;96(4):e575-e586. Epub 2020 Oct 5.

From the New York University Grossman School of Medicine (J.A.F., S.S., R.L., T.F., B.F., P.M.-V., T.S., S.B., D.Y., A.G., N.M., P.P., J.G., K.M., S.A., M.B., A.A., E.V., M.O., A.K., K.L., Daniel Friedman, David Friedman, M.H., J.H., S.T., J.H., N.A.-F., P.K., A.L., A.S.L., T.Z., D.E.K., B.M.C., J.T., S.Y., K.I., E.S., D.P., M.L., T.W., A.B.T., L.B., S.G.), New YorkUniversity of Pittsburgh School of Medicine (S.H.-Y.C., E.L.F.), PAThe Ohio State University (M.M., S.M.), ColumbusMedical University of Innsbruck (R.H.), AustriaThe Johns Hopkins University School of Medicine (C.R., J.I.S., W.Z.), Baltimore, MDUniversity of Utah School of Medicine (M.S., A.d.H.), Salt Lake CityUniversity of Cambridge (D.M.), UK.

Objective: To determine the prevalence and associated mortality of well-defined neurologic diagnoses among patients with coronavirus disease 2019 (COVID-19), we prospectively followed hospitalized severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-positive patients and recorded new neurologic disorders and hospital outcomes.

Methods: We conducted a prospective, multicenter, observational study of consecutive hospitalized adults in the New York City metropolitan area with laboratory-confirmed SARS-CoV-2 infection. The prevalence of new neurologic disorders (as diagnosed by a neurologist) was recorded and in-hospital mortality and discharge disposition were compared between patients with COVID-19 with and without neurologic disorders.

Results: Of 4,491 patients with COVID-19 hospitalized during the study timeframe, 606 (13.5%) developed a new neurologic disorder in a median of 2 days from COVID-19 symptom onset. The most common diagnoses were toxic/metabolic encephalopathy (6.8%), seizure (1.6%), stroke (1.9%), and hypoxic/ischemic injury (1.4%). No patient had meningitis/encephalitis or myelopathy/myelitis referable to SARS-CoV-2 infection and 18/18 CSF specimens were reverse transcriptase PCR negative for SARS-CoV-2. Patients with neurologic disorders were more often older, male, white, hypertensive, diabetic, intubated, and had higher sequential organ failure assessment (SOFA) scores (all < 0.05). After adjusting for age, sex, SOFA scores, intubation, history, medical complications, medications, and comfort care status, patients with COVID-19 with neurologic disorders had increased risk of in-hospital mortality (hazard ratio [HR] 1.38, 95% confidence interval [CI] 1.17-1.62, < 0.001) and decreased likelihood of discharge home (HR 0.72, 95% CI 0.63-0.85, < 0.001).

Conclusions: Neurologic disorders were detected in 13.5% of patients with COVID-19 and were associated with increased risk of in-hospital mortality and decreased likelihood of discharge home. Many observed neurologic disorders may be sequelae of severe systemic illness.
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http://dx.doi.org/10.1212/WNL.0000000000010979DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7905791PMC
January 2021

Prevalence and Impact of Hyponatremia in Patients With Coronavirus Disease 2019 in New York City.

Crit Care Med 2020 12;48(12):e1211-e1217

Department of Medicine, NYU Grossman School of Medicine, New York, NY.

Objectives: Hyponatremia occurs in up to 30% of patients with pneumonia and is associated with increased morbidity and mortality. The prevalence of hyponatremia associated with coronavirus disease 2019 and the impact on outcome is unknown. We aimed to identify the prevalence, predictors, and impact on outcome of mild, moderate, and severe admission hyponatremia compared with normonatremia among coronavirus disease 2019 patients.

Design: Retrospective, multicenter, observational cohort study.

Setting: Four New York City hospitals that are part of the same health network.

Patients: Hospitalized, laboratory-confirmed adult coronavirus disease 2019 patients admitted between March 1, 2020, and May 13, 2020.

Interventions: None.

Measurements And Main Results: Hyponatremia was categorized as mild (sodium: 130-134 mmol/L), moderate (sodium: 121-129 mmol/L), or severe (sodium: ≤ 120 mmol/L) versus normonatremia (135-145 mmol/L). The primary outcome was the association of increasing severity of hyponatremia and in-hospital mortality assessed using multivariable logistic regression analysis. Secondary outcomes included encephalopathy, acute renal failure, mechanical ventilation, and discharge home compared across sodium levels using Kruskal-Wallis and chi-square tests. In exploratory analysis, the association of sodium levels and interleukin-6 levels (which has been linked to nonosmotic release of vasopressin) was assessed. Among 4,645 patient encounters, hyponatremia (sodium < 135 mmol/L) occurred in 1,373 (30%) and 374 of 1,373 (27%) required invasive mechanical ventilation. Mild, moderate, and severe hyponatremia occurred in 1,032 (22%), 305 (7%), and 36 (1%) patients, respectively. Each level of worsening hyponatremia conferred 43% increased odds of in-hospital death after adjusting for age, gender, race, body mass index, past medical history, admission laboratory abnormalities, admission Sequential Organ Failure Assessment score, renal failure, encephalopathy, and mechanical ventilation (adjusted odds ratio, 1.43; 95% CI, 1.08-1.88; p = 0.012). Increasing severity of hyponatremia was associated with encephalopathy, mechanical ventilation, and decreased probability of discharge home (all p < 0.001). Higher interleukin-6 levels correlated with lower sodium levels (p = 0.017).

Conclusions: Hyponatremia occurred in nearly a third of coronavirus disease 2019 patients, was an independent predictor of in-hospital mortality, and was associated with increased risk of encephalopathy and mechanical ventilation.
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http://dx.doi.org/10.1097/CCM.0000000000004605DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7467047PMC
December 2020

Acute stroke care in a New York City comprehensive stroke center during the COVID-19 pandemic.

J Stroke Cerebrovasc Dis 2020 Sep 20;29(9):105068. Epub 2020 Jun 20.

Department of Neurology, New York Langone Health, New York, NY, United States. Electronic address:

Background And Purpose: The coronavirus disease-2019 (COVID-19) pandemic caused unprecedented demand and burden on emergency health care services in New York City. We aim to describe our experience providing acute stroke care at a comprehensive stroke center (CSC) and the impact of the pandemic on the quality of care for patients presenting with acute ischemic stroke (AIS).

Methods: We retrospectively analyzed data from a quality improvement registry of consecutive AIS patients at New York University Langone Health's CSC between 06/01/2019-05/15/2020. During the early stages of the pandemic, the acute stroke process was modified to incorporate COVID-19 screening, testing, and other precautionary measures. We compared stroke quality metrics including treatment times and discharge outcomes of AIS patients during the pandemic (03/012020-05/152020) compared with a historical pre-pandemic group (6/1/2019-2/29/2020).

Results: A total of 754 patients (pandemic-120; pre-pandemic-634) were admitted with a principal diagnosis of AIS; 198 (26.3%) received alteplase and/or mechanical thrombectomy. Despite longer median door to head CT times (16 vs 12 minutes; p = 0.05) and a trend towards longer door to groin puncture times (79.5 vs. 71 min, p = 0.06), the time to alteplase administration (36 vs 35 min; p = 0.83), door to reperfusion times (103 vs 97 min, p = 0.18) and defect-free care (95.2% vs 94.7%; p = 0.84) were similar in the pandemic and pre-pandemic groups. Successful recanalization rates (TICI≥2b) were also similar (82.6% vs. 86.7%, p = 0.48). After adjusting for stroke severity, age and a prior history of transient ischemic attack/stroke, pandemic patients had increased discharge mortality (adjusted OR 2.90 95% CI 1.77 - 7.17, p = 0.021) CONCLUSION: Despite unprecedented demands on emergency healthcare services, early multidisciplinary efforts to adapt the acute stroke treatment process resulted in keeping the stroke quality time metrics close to pre-pandemic levels. Future studies will be needed with a larger cohort comparing discharge and long-term outcomes between pre-pandemic and pandemic AIS patients.
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http://dx.doi.org/10.1016/j.jstrokecerebrovasdis.2020.105068DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7305900PMC
September 2020

Anticoagulation Type and Early Recurrence in Cardioembolic Stroke: The IAC Study.

Stroke 2020 09 6;51(9):2724-2732. Epub 2020 Aug 6.

Department of Neurology, Spectrum Health, Grand Rapids, MI (H.P., H.M., J.T., M.V., M.K.).

Background And Purpose: In patients with acute ischemic stroke and atrial fibrillation, treatment with low molecular weight heparin increases early hemorrhagic risk without reducing early recurrence, and there is limited data comparing warfarin to direct oral anticoagulant (DOAC) therapy. We aim to compare the effects of the treatments above on the risk of 90-day recurrent ischemic events and delayed symptomatic intracranial hemorrhage.

Methods: We included consecutive patients with acute ischemic stroke and atrial fibrillation from the IAC (Initiation of Anticoagulation after Cardioembolic) stroke study pooling data from stroke registries of 8 comprehensive stroke centers across the United States. We compared recurrent ischemic events and delayed symptomatic intracranial hemorrhage between each of the following groups in separate Cox-regression analyses: (1) DOAC versus warfarin and (2) bridging with heparin/low molecular weight heparin versus no bridging, adjusting for pertinent confounders to test these associations.

Results: We identified 1289 patients who met the bridging versus no bridging analysis inclusion criteria and 1251 patients who met the DOAC versus warfarin analysis inclusion criteria. In adjusted Cox-regression models, bridging (versus no bridging) treatment was associated with a high risk of delayed symptomatic intracranial hemorrhage (hazard ratio, 2.74 [95% CI, 1.01-7.42]) but a similar rate of recurrent ischemic events (hazard ratio, 1.23 [95% CI, 0.63-2.40]). Furthermore, DOAC (versus warfarin) treatment was associated with a lower risk of recurrent ischemic events (hazard ratio, 0.51 [95% CI, 0.29-0.87]) but not delayed symptomatic intracranial hemorrhage (hazard ratio, 0.57 [95% CI, 0.22-1.48]).

Conclusions: Our study suggests that patients with ischemic stroke and atrial fibrillation would benefit from the initiation of a DOAC without bridging therapy. Due to our study limitations, these findings should be interpreted with caution pending confirmation from large prospective studies.
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http://dx.doi.org/10.1161/STROKEAHA.120.028867DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7484360PMC
September 2020

Anticoagulation Timing in Cardioembolic Stroke and Recurrent Event Risk.

Ann Neurol 2020 10 5;88(4):807-816. Epub 2020 Aug 5.

Department of Neurology, Brown University, Providence, Rhode Island, USA.

Objective: Guidelines recommend initiating anticoagulation within 4 to 14 days after cardioembolic stroke. Data supporting this did not account for key factors potentially affecting the decision to initiate anticoagulation, such as infarct size, hemorrhagic transformation, or high-risk features on echocardiography.

Methods: We pooled data from stroke registries of 8 comprehensive stroke centers across the United States. We included consecutive patients admitted with ischemic stroke and atrial fibrillation. The primary predictor was timing of initiating anticoagulation (0-3 days, 4-14 days, or >14 days), and outcomes were recurrent stroke/transient ischemic attack/systemic embolism, symptomatic intracerebral hemorrhage (sICH), and major extracranial hemorrhage (ECH) within 90 days.

Results: Among 2,084 patients, 1,289 met the inclusion criteria. The combined endpoint occurred in 10.1% (n = 130) subjects (87 ischemic events, 20 sICH, and 29 ECH). Overall, there was no significant difference in the composite endpoint between the 3 groups (0-3 days: 10.3%, 64/617; 4-14 days: 9.7%, 52/535; >14 days: 10.2%, 14/137; p = 0.933). In adjusted models, patients started on anticoagulation between 4 and 14 days did not have a lower rate of sICH (vs 0-3 days; odds ratio [OR] = 1.49, 95% confidence interval [CI] = 0.50-4.43), nor did they have a lower rate of recurrent ischemic events (vs >14 days; OR = 0.76, 95% CI = 0.36-1.62, p = 0.482).

Interpretation: In this multicenter real-world cohort, the recommended (4-14 days) time frame to start oral anticoagulation was not associated with reduced ischemic and hemorrhagic outcomes. Randomized trials are required to determine the optimal timing of anticoagulation initiation. ANN NEUROL 2020;88:807-816.
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http://dx.doi.org/10.1002/ana.25844DOI Listing
October 2020

Stroke Treatment Delay Limits Outcome After Mechanical Thrombectomy: Stratification by Arrival Time and ASPECTS.

J Neuroimaging 2020 09 27;30(5):625-630. Epub 2020 Jun 27.

Department of Neurology, New York Langone Medical Center, New York, NY.

Background And Purpose: Mechanical thrombectomy (MT) has helped many patients achieve functional independence. The effect of time-to-treatment based in specific epochs and as related to Alberta Stroke Program Early CT Score (ASPECTS) has not been established. The goal of the study was to evaluate the association between last known normal (LKN)-to-puncture time and good functional outcome.

Methods: We conducted a retrospective cohort study of prospectively collected acute ischemic stroke patients undergoing MT for large vessel occlusion. We used binary logistic regression models adjusted for age, Modified Treatment in Cerebral Ischemia score, initial National Institutes of Health Stroke Scale, and noncontrast CT ASPECTS to assess the association between LKN-to-puncture time and favorable outcome defined as Modified Rankin Score 0-2 on discharge.

Results: Among 421 patients, 328 were included in analysis. Increased LKN-to-puncture time was associated with decreased probability of good functional outcome (adjusted odds ratio [aOR] ratio per 15-minute delay = .98; 95% confidence interval [CI], .97-.99; P = .001). This was especially true when LKN-puncture time was 0-6 hours (aOR per 15-minute delay = .94; 95% CI, .89-.99; P = .05) or ASPECTS 8-10 (aOR = .98; 95% CI, .97-.99; P = .002) as opposed to when LKN-puncture time was 6-24 hours (aOR per 15-minute delay = .99; 95% CI, .97-1.00; P = .16) and ASPECTS <8 (aOR = .98; 95% CI, .93-1.03; P = .37).

Conclusion: Decreased LKN-groin puncture time improves outcome particularly in those with good ASPECTS presenting within 6 hours. Strategies to decrease reperfusion times should be investigated, particularly in those in the early time window and with good ASPECTS.
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http://dx.doi.org/10.1111/jon.12729DOI Listing
September 2020

SARS-CoV-2 and Stroke in a New York Healthcare System.

Stroke 2020 07 20;51(7):2002-2011. Epub 2020 May 20.

Department of Neurology (S.Y., K.I., J.T., K.H., T.T., K.L., S.A., M.S., S.K., E.S., A.L., J.F.), NYU Langone Health, New York, NY.

Background And Purpose: With the spread of coronavirus disease 2019 (COVID-19) during the current worldwide pandemic, there is mounting evidence that patients affected by the illness may develop clinically significant coagulopathy with thromboembolic complications including ischemic stroke. However, there is limited data on the clinical characteristics, stroke mechanism, and outcomes of patients who have a stroke and COVID-19.

Methods: We conducted a retrospective cohort study of consecutive patients with ischemic stroke who were hospitalized between March 15, 2020, and April 19, 2020, within a major health system in New York, the current global epicenter of the pandemic. We compared the clinical characteristics of stroke patients with a concurrent diagnosis of COVID-19 to stroke patients without COVID-19 (contemporary controls). In addition, we compared patients to a historical cohort of patients with ischemic stroke discharged from our hospital system between March 15, 2019, and April 15, 2019 (historical controls).

Results: During the study period in 2020, out of 3556 hospitalized patients with diagnosis of COVID-19 infection, 32 patients (0.9%) had imaging proven ischemic stroke. Cryptogenic stroke was more common in patients with COVID-19 (65.6%) as compared to contemporary controls (30.4%, =0.003) and historical controls (25.0%, <0.001). When compared with contemporary controls, COVID-19 positive patients had higher admission National Institutes of Health Stroke Scale score and higher peak D-dimer levels. When compared with historical controls, COVID-19 positive patients were more likely to be younger men with elevated troponin, higher admission National Institutes of Health Stroke Scale score, and higher erythrocyte sedimentation rate. Patients with COVID-19 and stroke had significantly higher mortality than historical and contemporary controls.

Conclusions: We observed a low rate of imaging-confirmed ischemic stroke in hospitalized patients with COVID-19. Most strokes were cryptogenic, possibly related to an acquired hypercoagulability, and mortality was increased. Studies are needed to determine the utility of therapeutic anticoagulation for stroke and other thrombotic event prevention in patients with COVID-19.
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http://dx.doi.org/10.1161/STROKEAHA.120.030335DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7258764PMC
July 2020

Factors associated with therapeutic anticoagulation status in patients with ischemic stroke and atrial fibrillation.

J Stroke Cerebrovasc Dis 2020 Jul 13;29(7):104888. Epub 2020 May 13.

Department of Neurology, University of Utah, Salt Lake City, UT, USA.

Background And Purpose: Understanding factors associated with ischemic stroke despite therapeutic anticoagulation is an important goal to improve stroke prevention strategies in patients with atrial fibrillation (AF). We aim to determine factors associated with therapeutic or supratherapeutic anticoagulation status at the time of ischemic stroke in patients with AF.

Methods: The Initiation of Anticoagulation after Cardioembolic stroke (IAC) study is a multicenter study pooling data from stroke registries of eight comprehensive stroke centers across the United States. Consecutive patients hospitalized with acute ischemic stroke in the setting of AF were included in the IAC cohort. For this study, we only included patients who reported taking warfarin at the time of the ischemic stroke. Patients not on anticoagulation and patients who reported use of a direct oral anticoagulant were excluded. Analyses were stratified based on therapeutic (INR ≥2) versus subtherapeutic (INR <2) anticoagulation status. We used binary logistic regression models to determine factors independently associated with anticoagulation status after adjustment for pertinent confounders. In particular, we sought to determine whether atherosclerosis with 50% or more luminal narrowing in an artery supplying the infarct (a marker for a competing atherosclerotic mechanism) and small stroke size (≤ 10 mL; implying a competing small vessel disease mechanism) related to anticoagulant status.

Results: Of the 2084 patients enrolled in the IAC study, 382 patients met the inclusion criteria. The mean age was 77.4 ± 10.9 years and 52.4% (200/382) were women. A total of 222 (58.1%) subjects presented with subtherapeutic INR. In adjusted models, small stroke size (OR 1.74 95% CI 1.10-2.76, p = 0.019) and atherosclerosis with 50% or more narrowing in an artery supplying the infarct (OR 1.96 95% CI 1.06-3.63, p = 0.031) were independently associated with INR ≥2 at the time of their index stroke.

Conclusion: Small stroke size (≤ 10 ml) and ipsilateral atherosclerosis with 50% or more narrowing may indicate a competing stroke mechanism. There may be important opportunities to improve stroke prevention strategies for patients with AF by targeting additional ischemic stroke mechanisms to improve patient outcomes.
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http://dx.doi.org/10.1016/j.jstrokecerebrovasdis.2020.104888DOI Listing
July 2020

Mechanical Thrombectomy in Nonagenarians: A Propensity Score Matched Analysis.

J Stroke Cerebrovasc Dis 2020 Jul 13;29(7):104870. Epub 2020 May 13.

Department of Neurology, NYU School of Medicine, New York, NY, USA. Electronic address:

Background: Little data exists on outcomes of mechanical thrombectomy (MT) in nonagenarians. We aimed to compare the procedural and discharge outcomes of MT for acute ischemic stroke (AIS) in nonagenarians versus younger patients.

Methods: Procedural outcomes and discharge disposition were compared in propensity score-matched groups of nonagenarians versus patients aged≤69 with AIS who underwent MT. Patients aged 70-89 were excluded in order to compare nonagenarians to a younger cohort that most closely approximates the age of patients in the seminal MT trials. Good discharge disposition was defined as a discharge to home or acute rehabilitation.

Results: Of 3010 AIS patients, 46/297(16%) nonagenarians underwent MT compared to 159/1337(12%) aged≤69 (P = 0.091). Of 78 propensity score-matched patients (N = 39 ≥90, N = 39 ≤69), the median admission NIHSS was 22 versus 20, median ASPECTS was 9 versus 9, pre-stroke mRS<4 was 82% versus 87%, 18% versus 8% received IV tPA, and mTICI≥2b was 90% versus 90%, respectively (all P>0.05). Revascularization time (569 versus 372 min), door to groin puncture time (82 versus 71 min) and groin puncture to revascularization times (39 versus 24 min) were similar in between nonagenarians and ≤69, respectively (both P>0.05). Symptomatic ICH (2.6% versus 10.3%; p = 0.165) and in-hospital death rates (10% vs 26%; p = 0.077) trended lower among nonagenarians versus aged≤69. Good discharge disposition occurred in 44% of nonagenarians versus 51% aged≤69 years (p = 0.496).

Conclusions: In propensity score analysis, 90% of nonagenarians achieved successful recanalization and almost half (44%) were discharged to home/acute rehabilitation, which was similar to a younger (aged≤69 years) cohort.
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http://dx.doi.org/10.1016/j.jstrokecerebrovasdis.2020.104870DOI Listing
July 2020

Early ischaemic and haemorrhagic complications after atrial fibrillation-related ischaemic stroke: analysis of the IAC study.

J Neurol Neurosurg Psychiatry 2020 07 13;91(7):750-755. Epub 2020 May 13.

Department of Neurology, Brown University Warren Alpert Medical School, Providence, Rhode Island, USA.

Introduction: Predictors of long-term ischaemic and haemorrhagic complications in atrial fibrillation (AF) have been studied, but there are limited data on predictors of early ischaemic and haemorrhagic complications after AF-associated ischaemic stroke. We sought to determine these predictors.

Methods: The Initiation of Anticoagulation after Cardioembolic stroke study is a multicentre retrospective study across that pooled data from consecutive patients with ischaemic stroke in the setting of AF from stroke registries across eight comprehensive stroke centres in the USA. The coprimary outcomes were recurrent ischaemic event (stroke/TIA/systemic arterial embolism) and delayed symptomatic intracranial haemorrhage (d-sICH) within 90 days. We performed univariate analyses and Cox regression analyses including important predictors on univariate analyses to determine independent predictors of early ischaemic events (stroke/TIA/systemic embolism) and d-sICH.

Results: Out of 2084 patients, 1520 patients qualified; 104 patients (6.8%) had recurrent ischaemic events and 23 patients (1.5%) had d-sICH within 90 days from the index event. In Cox regression models, factors associated with a trend for recurrent ischaemic events were prior stroke or transient ischemic attack (TIA) (HR 1.42, 95% CI 0.96 to 2.10) and ipsilateral arterial stenosis with 50%-99% narrowing (HR 1.54, 95% CI 0.98 to 2.43). Those associated with sICH were male sex (HR 2.68, 95% CI 1.06 to 6.83), history of hyperlipidaemia (HR 2.91, 95% CI 1.08 to 7.84) and early haemorrhagic transformation (HR 5.35, 95% CI 2.22 to 12.92).

Conclusion: In patients with ischaemic stroke and AF, predictors of d-sICH are different than those of recurrent ischaemic events; therefore, recognising these predictors may help inform early stroke versus d-sICH prevention strategies.
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http://dx.doi.org/10.1136/jnnp-2020-323041DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8179007PMC
July 2020

Redefined Measure of Early Neurological Improvement Shows Treatment Benefit of Alteplase Over Placebo.

Stroke 2020 04 27;51(4):1226-1230. Epub 2020 Feb 27.

From the Department of Neurology, New York Langone Health (S.A., E.S., A.L., J.F., K.I., J.T., S.R., S.Y.).

Background and Purpose- The first of the 2 NINDS (National Institute of Neurological Disorders and Stroke) Study trials did not show a significant increase in early neurological improvement, defined as National Institutes of Health Stroke Scale (NIHSS) improvement by ≥4, with alteplase treatment. We hypothesized that early neurological improvement defined as a percentage change in NIHSS (percent change NIHSS) at 24 hours is superior to other definitions in predicting 3-month functional outcomes and using this definition there would be treatment benefit of alteplase over placebo at 24 hours. Methods- We analyzed the NINDS rt-PA Stroke Study (Parts 1 and 2) trial data. Percent change NIHSS was defined as ([admission NIHSS score-24-hour NIHSS score]×100/admission NIHSS score] and delta NIHSS as (admission NIHSS score-24-hour NIHSS score). We compared early neurological improvement using these definitions between alteplase versus placebo patients. We also used receiver operating characteristic curve to determine the predictive association of early neurological improvement with excellent 3-month functional outcomes (Barthel Index score of 95-100 and modified Rankin Scale score of 0-1), good 3-month functional outcome (modified Rankin Scale score of 0-2), and 3-month infarct volume. Results- There was a significantly greater improvement in the 24-hour median percent change NIHSS among patients treated with alteplase compared with the placebo group (28% versus 15%; =0.045) but not median delta NIHSS (3 versus 2; =0.471). Receiver operating characteristic curve comparison showed that percent change NIHSS (ROC) was better than delta NIHSS (ROC) and admission NIHSS (ROC) with regards to excellent 3-month Barthel Index (ROC, 0.83; ROC, 0.76; ROC, 0.75), excellent 3-month modified Rankin Scale (ROC, 0.83; ROC, 0.74; ROC, 0.78), and good 3-month modified Rankin Scale (ROC, 0.83; ROC, 0.76; ROC, 0.78). Conclusions- In the NINDS rt-PA trial, alteplase was associated with a significant percent change improvement in NIHSS at 24 hours. Percent change in NIHSS may be a better surrogate marker of thrombolytic activity and 3-month outcomes.
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http://dx.doi.org/10.1161/STROKEAHA.119.027476DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7101071PMC
April 2020

Left Atrial Appendage Morphology Improves Prediction of Stagnant Flow and Stroke Risk in Atrial Fibrillation.

Circ Arrhythm Electrophysiol 2020 02 27;13(2):e008074. Epub 2020 Jan 27.

Division of Cardiovascular Medicine, Department of Internal Medicine (N.P., A. Chu, M.W., C.S.), The Warren Alpert Medical School of Brown University, Providence, RI.

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http://dx.doi.org/10.1161/CIRCEP.119.008074DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7446933PMC
February 2020

Redefining Early Neurological Improvement After Reperfusion Therapy in Stroke.

J Stroke Cerebrovasc Dis 2020 Feb 11;29(2):104526. Epub 2019 Dec 11.

Department of Neurology, New York Langone Health, New York, New York; Department of Neurology, The Warren Alpert Medical School of Brown University, Providence, Rhode Island. Electronic address:

Background And Purpose: Early neurologic improvement (ENI) in patients treated with alteplase has been shown to correlate with functional outcome. However, the definition of ENI remains controversial and has varied across studies. We hypothesized that ENI defined as a percentage change in the National Institute of Health Stroke Scale (NIHSS) score (percent change NIHSS score) at 24-hours would better correlate with favorable outcomes at 3 months than ENI defined as the change in NIHSS score (delta NIHSS score) at 24 hours.

Methods: Retrospective analysis of prospectively collected single-center quality improvement data was performed of all acute ischemic stroke (AIS) patients treated with alteplase. We examined delta NIHSS score and percent change NIHSS score in unadjusted and adjusted logistic regression models as predictors of a favorable outcome at 3 months (defined as mRS 0-1).

Results: Among 586 patients who met the inclusion criteria, 194 (33.1%) had a favorable outcome at 3 months. In fully adjusted models, both delta NIHSS score (OR per point decrease 1.27; 95% confidence interval [CI] 1.19-1.36) and percent change NIHSS score (OR per 10 percent decrease 1.17; 95% CI 1.12-1.22) were associated with favorable functional outcome at 3 months. Receiver operating characteristic (ROC) curve comparison showed that the area under the ROC curve for percent change NIHSS score (.755) was greater than delta NIHSS score (.613) or admission NIHSS (.694).

Conclusions: Percentage change in NIHSS score may be a better surrogate marker of ENI and functional outcome in AIS patients after receiving acute thrombolytic therapy. More studies are needed to confirm our findings.
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http://dx.doi.org/10.1016/j.jstrokecerebrovasdis.2019.104526DOI Listing
February 2020

Predicting symptomatic intracranial haemorrhage after mechanical thrombectomy: the TAG score.

J Neurol Neurosurg Psychiatry 2019 12 19;90(12):1370-1374. Epub 2019 Aug 19.

Neurology, Columbia University Medical Center, New York City, New York, USA

Background: There is limited data on predictors of symptomatic intracranial haemorrhage (sICH) in patients who underwent mechanical thrombectomy. In this study, we aim to determine those predictors with external validation.

Methods: We evaluated mechanical thrombectomy in a derivation cohort of patients at a comprehensive stroke centre over a 30-month period. Clinical and radiographic data on these patients were obtained from the prospective quality improvement database. sICH was defined using the European Cooperative Acute Stroke Study III. We compared clinical and radiographic characteristics between patients with and without sICH using χ and t tests to identify independent predictors of sICH with p<0.1. Significant variables were then combined in a multivariate logistic regression model to derive an sICH prediction score. This score was then validated using data from the Blood Pressure After Endovascular Treatment multicentre prospective registry.

Results: We identified 578 patients with acute ischaemic stroke who received thrombectomy, 19 had sICH (3.3%). Predictive factors of sICH were: thrombolysis in cerebral ischaemia (TICI) score, Alberta stroke program early CT score (ASPECTS), and glucose level, and from these predictors, we derived the weighted TICI-ASPECTS-glucose (TAG) score, which was associated with sICH in the derivation (OR per unit increase 1.98, 95% CI 1.48 to 2.66, p<0.001, area under curve ((AUC)=0.79) and validation (OR per unit increase 1.48, 95% CI 1.22 to 1.79, p<0.001, AUC=0.69) cohorts.

Conclusion: High TAG scores are associated with sICH in patients receiving mechanical thrombectomy. Larger studies are needed to validate this scoring system and test strategies to reduce sICH risk and make thrombectomy safer in patients with elevated TAG scores.
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http://dx.doi.org/10.1136/jnnp-2019-321184DOI Listing
December 2019

Maternal active and passive smoking and hypertensive disorders of pregnancy: risk with trimester-specific exposures.

Epidemiology 2013 May;24(3):379-86

Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC 27599, USA.

Background: The inverse association between prenatal smoking and preeclampsia is puzzling, given the increased risks of prematurity and low birthweight associated with both smoking and preeclampsia. We analyzed the Norwegian Mother and Child Birth Cohort (MoBa) to determine whether the associations varied by timing of prenatal smoking.

Methods: We conducted an analysis of 74,439 singleton pregnancies with completed second- and third- trimester questionnaires. Active and passive smoke exposure by trimester were determined by maternal self-report, and covered the period of preconception through approximately 30 weeks' gestation. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were calculated.

Results: Rates of active smoking declined dramatically during pregnancy: for trimester 1, 23%; trimester 2, 9%; and trimester 3, 8%. Active smoking in the third trimester was associated with reduced odds of preeclampsia and gestational hypertension, with the strongest association among continuous smokers (for preeclampsia, OR= 0.57 [95% CI = 0.46-0.70]). Women who quit smoking before the third trimester had approximately the same risk of preeclampsia and gestational hypertension as nonsmokers. There was some evidence of dose-response, with the heaviest smokers (more than eight cigarettes per day) having the lowest risks of preeclampsia (0.48 [0.32-0.73]) and gestational hypertension (0.51 [0.28-0.95]). There was little evidence of an association with passive smoking exposure.

Conclusion: The association between smoking and preeclampsia varies substantially according to the timing and intensity of exposure. A better understanding of the biologic pathways that underlie these associations may provide important clues to the etiology of preeclampsia and the development of effective clinical interventions.
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http://dx.doi.org/10.1097/EDE.0b013e3182873a73DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4137974PMC
May 2013

Localized mucosal response to intranasal live attenuated influenza vaccine in adults.

J Infect Dis 2013 Jan 19;207(1):115-24. Epub 2012 Oct 19.

Department of Microbiology, Mount Sinai School of Medicine, New York, New York 10029, USA.

Background: Influenza virus infection is a major public health burden worldwide. Available vaccines include the inactivated intramuscular trivalent vaccine and, more recently, an intranasal live attenuated influenza vaccine (LAIV). The measure of successful vaccination with the inactivated vaccine is a systemic rise in immunoglobulin G (IgG) level, but for the LAIV no such correlate has been established.

Methods: Seventy-nine subjects were given the LAIV FluMist. Blood was collected prior to vaccination and 3 days and 30 days after vaccination. Nasal wash was collected 3 days and 30 days after vaccination. Responses were measured systemically and in mucosal secretions for cytokines, cell activation profiles, and antibody responses.

Results: Only 9% of subjects who received LAIV seroconverted, while 33% of patients developed at least a 2-fold increase in influenza virus-specific immunoglobulin A (IgA) antibodies in nasal wash. LAIV induced a localized inflammation, as suggested by increased expression of interferon-response genes in mucosal RNA and increased granulocyte colony-stimulating factor (G-CSF) and IP-10 in nasal wash. Interestingly, patients who seroconverted had significantly lower serum levels of G-CSF before vaccination.

Conclusions: Protection by LAIV is likely provided through mucosal IgA and not by increases in systemic IgG. LAIV induces local inflammation. Seroconversion is achieved in a small fraction of subjects with a lower serum G-CSF level.
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http://dx.doi.org/10.1093/infdis/jis641DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3571238PMC
January 2013

Extended characterisation of the serotonin 2A (5-HT2A) receptor-selective PET radiotracer 11C-MDL100907 in humans: quantitative analysis, test-retest reproducibility, and vulnerability to endogenous 5-HT tone.

Neuroimage 2012 Jan 18;59(1):271-85. Epub 2011 Jul 18.

Department of Psychiatry, Columbia University College of Physicians and Surgeons and the New York State Psychiatric Institute, New York, NY 10032, USA.

Introduction: Scanning properties and analytic methodology of the 5-HT2A receptor-selective positron emission tomography (PET) tracer 11C-MDL100907 have been partially characterised in previous reports. We present an extended characterisation in healthy human subjects.

Methods: 64 11C-MDL100907 PET scans with metabolite-corrected arterial input function were performed in 39 healthy adults (18-55 years). 12 subjects were scanned twice (duration 150 min) to provide data on plasma analysis, model order estimation, and stability and test-retest characteristics of outcome measures. All other scans were 90 min duration. 3 subjects completed scanning at baseline and following 5-HT2A receptor antagonist medication (risperidone or ciproheptadine) to provide definitive data on the suitability of the cerebellum as reference region. 10 subjects were scanned under reduced 5-HT and control conditions using rapid tryptophan depletion to investigate vulnerability to competition with endogenous 5-HT. 13 subjects were scanned as controls in clinical protocols. Pooled data were used to analyse the relationship between tracer injected mass and receptor occupancy, and age-related decline in 5-HT2A receptors.

Results: Optimum analytic method was a 2-tissue compartment model with arterial input function. However, basis function implementation of SRTM may be suitable for measuring between-group differences non-invasively and warrants further investigation. Scan duration of 90 min achieved stable outcome measures in all cortical regions except orbitofrontal which required 120 min. Binding potential (BPP and BPND) test-retest variability was very good (7-11%) in neocortical regions other than orbitofrontal, and moderately good (14-20%) in orbitofrontal cortex and medial temporal lobe. Saturation occupancy of 5-HT2A receptors by risperidone validates the use of the cerebellum as a region devoid of specific binding for the purposes of PET. We advocate a mass limit of 4.6 μg to remain below 5% receptor occupancy. 11C-MDL100907 specific binding is not vulnerable to competition with endogenous 5-HT in humans. Paradoxical decreases in BPND were found in right prefrontal cortex following reduced 5-HT, possibly representing receptor internalisation. Mean age-related decline in brain 5-HT2A receptors was 14.0±5.0% per decade, and higher in prefrontal regions.

Conclusions: Our data confirm and extend support for 11C-MDL100907 as a PET tracer with very favourable properties for quantifying 5-HT2A receptors in the human brain.
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http://dx.doi.org/10.1016/j.neuroimage.2011.07.001DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3195881PMC
January 2012

Dopamine (D2/3) receptor agonist positron emission tomography radiotracer [11C]-(+)-PHNO is a D3 receptor preferring agonist in vivo.

Synapse 2006 Dec;60(7):485-95

Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York 10032, USA.

[11C]PHNO is a recently introduced agonist to image DA D2-like receptors with Positron Emission Tomography (PET). In cats and humans, [11C]PHNO revealed an atypical distribution compared to radiolabeled D2-like antagonists (such as [11C]raclopride) or other D2-like agonists (such as [11C]NPA), as it displayed unusual high binding in the globus pallidus (GP). The goal of this study was to assess the pharmacological nature of the binding of [11C]PHNO in the GP in nonhuman primates. As previously reported in humans, [11C]PHNO equilibrium specific to nonspecific equilibrium partition coefficients (V3'') in baboons was much higher in GP (3.88 +/- 1.15) than in the dorsal striatum (DST, 2.07 +/- 0.43), whereas the reverse was true for [11C]raclopride (1.48 +/- 0.41 in GP, 2.56 +/- 0.91 in DST) and [11C]NPA (0.87 +/- 0.19 in GP, 1.02 +/- 0.13 in DST). Administration of unlabeled raclopride resulted in similar reductions of [11C] PHNO V3'' and [11C]raclopride V3'' in both the GP and the DST. This observation demonstrated that the [11C]PHNO binding in the GP was specific to D2-like receptors. To evaluate the respective contribution of D3 and D2 receptors to the binding potential (BP) of [11C]PHNO and [11C]raclopride, experiments were carried out with the selective D3 partial agonist 1-(4(2-Napthoylamino)butyl)-4-(2-methoxyphenyl)-1A-piperazine HCL (BP897). BP897 reduced [11C]raclopride V3'' by 29% +/- 9%, 19% +/- 8%, and 10% +/- 7% in GP, VST, and DST, respectively, a result consistent with expectation from postmortem studies (D3/D2 ratio in GP > VST > DST). BP897 reduced [11C]PHNO V3'' by 57% +/- 11%, 30% +/- 11%, and 13% +/- 8% in GP, VST, and DST, respectively, indicating that the D3 receptor contribution to [11C]PHNO signal is higher than that of [11C]raclopride. From these experiments we conclude that [11C]PHNO is a D3 preferring agonist, and that this property explains the high GP signal not observed with [11C]raclopride or [11C]NPA. This property might contribute to its higher vulnerability to endogenous DA compared to [11C]raclopride and [11C]NPA.
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http://dx.doi.org/10.1002/syn.20325DOI Listing
December 2006

Measurement of the proportion of D2 receptors configured in state of high affinity for agonists in vivo: a positron emission tomography study using [11C]N-propyl-norapomorphine and [11C]raclopride in baboons.

J Pharmacol Exp Ther 2005 Oct 12;315(1):80-90. Epub 2005 Jul 12.

New York State Psychiatric Institute, 1051 Riverside Dr., Box #31, New York, NY 10032, USA.

Dopamine D2 receptors are configured in interconvertible states of high (D(2 high)) or low (D(2 low)) affinity for agonists. The in vivo proportion of sites in high-affinity state remains poorly documented. Previous studies have established the D2 agonist [11C]N-propyl-norapomorphine (NPA) as a suitable positron emission tomography radiotracer for imaging D(2 high) in the living brain. To elucidate the proportion of D2 receptors configured in D(2 high) states in vivo, imaging studies were conducted in three baboons with both [11C]NPA and the D2 receptor antagonist [11C]raclopride. These studies were performed under noncarrier- and carrier-added conditions, to compare the Bmax of [11C]NPA and [11C]raclopride in the same animals. [11C]raclopride in vivo KD and Bmax were 1.59 +/- 0.28 nM (n = 3) and 27.3 +/- 3.9 nM (n = 3), respectively. The in vivo KD of [11C]NPA was 0.16 +/- 0.01 nM (n = 3), consistent with its affinity for D(2 high) reported in vitro. The maximal density of sites for [11C]NPA was 21.6 +/- 2.8 nM (n = 3), i.e., 79% of the [11C]raclopride Bmax. This result suggested that 79% of D2 receptors are configured as D(2 high) in vivo. This large proportion of D(2 high) sites might explain the vulnerability of D2 radiotracers to competition by endogenous dopamine, and is consistent with a previous report that the in vivo binding of agonist radiotracer [11C]NPA is more vulnerable to competition by endogenous dopamine than that of antagonist radiotracer [11C]raclopride.
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http://dx.doi.org/10.1124/jpet.105.090068DOI Listing
October 2005