Publications by authors named "Paula Diehr"

79 Publications

Physical Function and Survival in Older Adults: A longitudinal study accounting for time-varying effects.

Arch Gerontol Geriatr 2021 May 24;96:104440. Epub 2021 May 24.

Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, Quebec; Department of Medicine, McGill University Montreal, Quebec; Research Institute of the McGill University Health Centre, Montreal, Quebec.

Purpose Of The Study: Variation in physical function in older adults over time raises several methodological challenges in the study of its association with survival, many of which have largely been overlooked in previous studies. The objective of this study is to examine the relationship between time-varying measures of physical function and survival in men and women aged 70 years and over, while accounting for the time-varying effects of health and lifestyle characteristics.

Methods: 1,846 women and 1,245 men in the Cardiovascular Health Study followed annually for up to 10 years beginning at age 70-74 years were included. We estimated the effect of gait speed and grip strength on survival over the subsequent year, using age as the timescale.

Results: A 0.1m/s higher gait speed was associated with a 12% decrease in the likelihood of death in the subsequent year among women (HR 0.88, 95% CI 0.82-0.94). There was no statistically significant effect of gait speed on survival among men (HR 0.97, 95% CI 0.91 to 1.03), or of grip strength on survival among women (HR 0.97, 95% CI 0.95-1.00) or men (HR 0.99, 95% CI 0.97-1.01), over one year.

Conclusions: Upon using time-varying measures of physical function while accounting for time-varying effects of health and lifestyle characteristics, higher gait speed was associated with increased survival among the women in our study. We found no evidence of an association between gait speed and one-year survival in men, or between grip strength and one-year survival in women or men.
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http://dx.doi.org/10.1016/j.archger.2021.104440DOI Listing
May 2021

The association between physical function and proximity to death in older adults: a multilevel analysis of 4,150 decedents from the Cardiovascular Health Study.

Ann Epidemiol 2019 07 18;35:59-65.e5. Epub 2019 Apr 18.

Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, Quebec, Canada; Department of Medicine, McGill University, Montreal, Quebec, Canada.

Purpose: When examining whether poor physical function is a risk factor for imminent death in older adults, one challenge is the lack of a meaningful time origin, a time point on which the estimate of time-to-death is anchored. In this study, we overcame this challenge by discarding the traditional-and flawed-approach of survival analysis with "time since beginning of follow up" as the time variable, and instead used a novel analytic approach that uses time-to-death as a covariate to examine its association with physical function.

Methods: Physical function and other covariates were measured annually in the Cardiovascular Health Study on 4150 individuals followed up to their time of death. Using multilevel models, we estimated gait speed and grip strength in relation to two time axes: age and proximity to death.

Results: As individuals approached death, both gait speed and grip strength decreased significantly. However, after adjustment for health and lifestyle covariates, there was significant variation in the level of physical function between individuals.

Conclusion: Although physical function was significantly associated with time-to-death, there was significant variation in level of physical function between individuals at comparable proximity to death. A better understanding of these variations is needed before measures of physical function are recommended as a clinical tool for identifying individuals at high risk of death.
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http://dx.doi.org/10.1016/j.annepidem.2019.04.005DOI Listing
July 2019

Can a Healthy Lifestyle Compress the Disabled Period in Older Adults?

J Am Geriatr Soc 2016 10 7;64(10):1952-1961. Epub 2016 Sep 7.

Department of Epidemiology, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, Pennsylvania.

Objectives: To determine whether lifestyle factors, measured late in life, could compress the disabled period toward the end of life.

Design: Community-based cohort study of older adults followed from 1989 to 2015.

Setting: Four U.S. communities.

Participants: Community-living men and women aged 65 and older (N = 5,248, mean age 72.7 ± 5.5, 57% female, 15.2% minority) who were not wheelchair dependent and were able to give informed consent at baseline.

Measurements: Multiple lifestyle factors, including smoking, alcohol consumption, physical activity, diet, body mass index (BMI), social networks, and social support, were measured at baseline. Activities of daily living (ADLs) were assessed at baseline and throughout follow-up. Years of life (YoL) was defined as years until death. Years of able life (YAL) was defined as years without any ADL difficulty. YAL/YoL%, the proportion of life lived able, was used to indicate the relative compression or expansion of the disabled period.

Results: The average duration of disabled years was 4.5 (out of 15.4 mean YoL) for women and 2.9 (out of 12.4 mean YoL) for men. In a multivariable model, obesity was associated with 7.3 percentage points (95% confidence interval (CI) = 5.4-9.2) lower YAL/YoL% than normal weight. Scores in the lowest quintile of the Alternate Healthy Eating Index were associated with a 3.7% (95% CI = 1.6-5.9) lower YAL/YoL% than scores in the highest quintile. Every 25 blocks walked in a week was associated with 0.5 percentage points (95% CI = 0.3-0.8) higher YAL/YoL%.

Conclusion: The effects of healthy lifestyle factors on the proportion of future life lived free of disability indicate that the disabled period can be compressed, given the right combination of these factors.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5073015PMC
http://dx.doi.org/10.1111/jgs.14314DOI Listing
October 2016

Sex, Race, and Age Differences in Observed Years of Life, Healthy Life, and Able Life among Older Adults in The Cardiovascular Health Study.

J Pers Med 2015 Nov 25;5(4):440-51. Epub 2015 Nov 25.

Department of Epidemiology, University of Pittsburgh, Pittsburgh, PA 15260, USA.

Objective: Longevity fails to account for health and functional status during aging. We sought to quantify differences in years of total life, years of healthy life, and years of able life among groups defined by age, sex, and race.

Design: Primary analysis of a cohort study.

Setting: 18 years of annual evaluations in four U.S. communities.

Participants: 5888 men and women aged 65 and older.

Measurements: Years of life were calculated as the time from enrollment to death or 18 years. Years of total, healthy, and able life were determined from self-report during annual or semi-annual contacts. Cumulative years were summed across each of the age and sex groups.

Results: White women had the best outcomes for all three measures, followed by white men, non-white women, and non-white men. For example, at the mean age of 73, a white female participant could expect 12.9 years of life, 8.9 of healthy life and 9.5 of able life, while a non-white female could expect 12.6, 7.0, and 8.0 years, respectively. A white male could expect 11.2, 8.1, and 8.9 years of life, healthy life, and able life, and a non-white male 10.3, 6.2, and 7.9 years. Regardless of starting age, individuals of the same race and sex groups spent similar amounts (not proportions) of time in an unhealthy or unable state.

Conclusion: Gender had a greater effect on longevity than did race, but race had a greater effect on years spent healthy or able. The mean number of years spent in an unable or sick state was surprisingly independent of the lifespan.
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http://dx.doi.org/10.3390/jpm5040440DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4695864PMC
November 2015

Predicting Future Years of Life, Health, and Functional Ability: A Healthy Life Calculator for Older Adults.

Gerontol Geriatr Med 2015 Jan-Dec;1:2333721415605989. Epub 2015 Oct 8.

University of Pittsburgh, PA, USA.

To create personalized estimates of future health and ability status for older adults. Data came from the Cardiovascular Health Study (CHS), a large longitudinal study. Outcomes included years of life, years of healthy life (based on self-rated health), years of able life (based on activities of daily living), and years of healthy and able life. We developed regression estimates using the demographic and health characteristics that best predicted the four outcomes. Internal and external validity were assessed. A prediction equation based on 11 variables accounted for about 40% of the variability for each outcome. Internal validity was excellent, and external validity was satisfactory. The resulting CHS Healthy Life Calculator (CHSHLC) is available at http://healthylifecalculator.org. CHSHLC provides a well-documented estimate of future years of healthy and able life for older adults, who may use it in planning for the future.
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http://dx.doi.org/10.1177/2333721415605989DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5119805PMC
October 2015

Brain imaging findings in elderly adults and years of life, healthy life, and able life over the ensuing 16 years: the Cardiovascular Health Study.

J Am Geriatr Soc 2014 Oct;62(10):1838-43

Department of Neurology, University of Washington, Seattle, Washington; Department of Epidemiology, University of Washington, Seattle, Washington.

Objectives: To determine whether elderly people with different patterns of magnetic resonance imaging (MRI) findings have different long-term outcomes.

Design: Longitudinal cohort study.

Setting: Cardiovascular Health Study.

Participants: Individuals aged 65 and older were recruited (N = 5,888); 3,660 of these underwent MRI, and 3,230 without a stroke before MRI were included in these analyses.

Measurements: Cluster analysis of brain MRI findings was previously used to define five clusters: normal, atrophy, simple infarct, leukoaraiosis, and complex infarct. Participants were subsequently classified as healthy if they rated their health as excellent, very good, or good and as able if they did not report any limitations in activities of daily living (ADLs). Mean years of life (YoL), years of healthy life (YHL), and years of able life (YAL) were calculated over 16 years after the MRI and compared between clusters using unadjusted and adjusted regression analyses.

Results: Mean age of participants was 75.0. With 16 years of follow-up, mean YoL was 11.3; YHL, 8.0; and YAL, 8.4. Outcomes differed significantly between clusters. With or without adjustments, outcomes were all significantly better in the normal than complex infarct cluster. The three remaining clusters had intermediate results, significantly different from the normal and complex infarct clusters but not usually from one another. Over 16 years of follow-up, participants in the complex infarct cluster (n = 368) spent the largest percentage of their 8.4 years alive being sick (38%) and not able (38%).

Conclusion: Findings on MRI scans in elderly adults are associated not only with long-term survival, but also with long-term self-rated health and limitation in ADLs. The combination of infarcts and leukoaraiosis carried the worst prognosis, presumably reflecting small vessel disease.
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http://dx.doi.org/10.1111/jgs.13068DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4205483PMC
October 2014

Disability and recovery of independent function in obstructive lung disease: the cardiovascular health study.

Respiration 2014 9;88(4):329-38. Epub 2014 Sep 9.

Health Services Research and Development, Department of Veterans Affairs, Seattle, Wash., USA.

Background: Chronic obstructive lung disease frequently leads to disability. Older patients may experience transitions between states of disability and independence over time.

Objective: To identify factors associated with transition between states of disability and independent function in obstructive lung disease.

Methods: We analyzed data on 4,394 participants in the Cardiovascular Health Study who completed prebronchodilator spirometry. We calculated the 1-year probability of developing and resolving impairment in ≥1 instrumental activity of daily living (IADL) or ≥1 activity of daily living (ADL) using transition probability analysis. We identified factors associated with resolving disability using relative risk (RR) regression.

Results: The prevalence of IADL impairment was higher with moderate (23.9%) and severe (36.9%) airflow obstruction compared to normal spirometry (22.5%; p < 0.001). Among participants with severe airflow obstruction, 23.5% recovered independence in IADLs and 40.5% recovered independence in ADLs. In the adjusted analyses, airflow obstruction predicted the development of IADL, but not ADL impairment. Participants with severe airflow obstruction were less likely to resolve IADL impairment [RR 0.67 and 95% confidence interval (CI) 0.49-0.94]. Compared to the most active individuals (i.e. who walked ≥28 blocks per week), walking less was associated with a decreased likelihood of resolving IADL impairment (7-27 blocks: RR 0.81 and 95% CI 0.69-0.86 and <7 blocks: RR 0.73 and 95% CI 0.61-0.86). Increased strength (RR 1.16 and 95% CI 1.05-1.29) was associated with resolving IADL impairment.

Conclusions: Disability is common in older people, especially in those with severe airflow obstruction. Increased physical activity and muscle strength are associated with recovery. Research is needed on interventions to improve these factors among patients with obstructive lung disease and disability.
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http://dx.doi.org/10.1159/000363772DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4197928PMC
October 2015

Effects of respiratory and non-respiratory factors on disability among older adults with airway obstruction: the Cardiovascular Health Study.

COPD 2013 Oct 2;10(5):588-96. Epub 2013 Jul 2.

1Health Services Research and Development, Department of Veterans Affairs, Seattle, WA, USA.

Background: High rates of disability associated with chronic airway obstruction may be caused by impaired pulmonary function, pulmonary symptoms, other chronic diseases, or systemic inflammation.

Methods: We analyzed data from the Cardiovascular Health Study, a longitudinal cohort of 5888 older adults. Categories of lung function (normal; restricted; borderline, mild-moderate, and severe obstruction) were delineated by baseline spirometry (without bronchodilator). Disability-free years were calculated as total years alive and without self-report of difficulty performing &γτ;1 Instrumental Activities of Daily Living over 6 years of follow-up. Using linear regression, we compared disability-free years by lung disease category, adjusting for demographic factors, body mass index, smoking, cognition, and other chronic co-morbidities. Among participants with airflow obstruction, we examined the association of respiratory factors (FEV1 and dyspnea) and non-respiratory factors (ischemic heart disease, congestive heart failure, diabetes, muscle weakness, osteoporosis, depression and cognitive impairment) on disability-free years.

Results: The average disability free years were 4.0 out of a possible 6 years. Severe obstruction was associated with 1 fewer disability-free year compared to normal spirometry in the adjusted model. For the 1,048 participants with airway obstruction, both respiratory factors (FEV1 and dyspnea) and non-respiratory factors (heart disease, coronary artery disease, diabetes, depression, osteoporosis, cognitive function, and weakness) were associated with decreased disability-free years.

Conclusions: Severe obstruction is associated with greater disability compared to patients with normal spirometery. Both respiratory and non-respiratory factors contribute to disability in older adults with abnormal spirometry.
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http://dx.doi.org/10.3109/15412555.2013.781148DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3903127PMC
October 2013

Decline in health for older adults: five-year change in 13 key measures of standardized health.

J Gerontol A Biol Sci Med Sci 2013 Sep 10;68(9):1059-67. Epub 2013 May 10.

Department of Biostatistics, University of Washington, 1959 NE Pacific Ave, Seattle, WA 98195, USA.

Background: The health of older adults declines over time, but there are many ways of measuring health. It is unclear whether all health measures decline at the same rate or whether some aspects of health are less sensitive to aging than others.

Methods: We compared the decline in 13 measures of physical, mental, and functional health from the Cardiovascular Health Study: hospitalization, bed days, cognition, extremity strength, feelings about life as a whole, satisfaction with the purpose of life, self-rated health, depression, digit symbol substitution test, grip strength, activities of daily living, instrumental activities of daily living, and gait speed. Each measure was standardized against self-rated health. We compared the 5-year change to see which of the 13 measures declined the fastest and the slowest.

Results: The 5-year change in standardized health varied from a decline of 12 points (out of 100) for hospitalization to a decline of 17 points for gait speed. In most comparisons, standardized health from hospitalization and bed days declined the least, whereas health measured by activities of daily living, instrumental activities of daily living, and gait speed declined the most. These rankings were independent of age, sex, mortality patterns, and the method of standardization.

Conclusions: All of the health variables declined, on average, with advancing age, but at significantly different rates. Standardized measures of mental health, cognition, quality of life, and hospital utilization did not decline as fast as gait speed, activities of daily living, and instrumental activities of daily living. Public health interventions to address problems with gait speed, activities of daily living, and instrumental activities of daily living may help older adults to remain healthier in all dimensions.
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http://dx.doi.org/10.1093/gerona/glt038DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3738029PMC
September 2013

Transitions among Health States Using 12 Measures of Successful Aging in Men and Women: Results from the Cardiovascular Health Study.

J Aging Res 2012 21;2012:243263. Epub 2012 Oct 21.

Department of Psychiatry, University of Washington, Seattle, WA 98195, USA ; Geriatrics Research, Education, and Clinical Center, Puget Sound VA Medical Center and Psychiatry and Behavioral Sciences, University of Washington, P.O. Box 356560, Seattle, WA 98195, USA.

Introduction. Successful aging has many dimensions, which may manifest differently in men and women at different ages. Methods. We characterized one-year transitions among health states in 12 measures of successful aging among adults in the Cardiovascular Health Study. The measures included self-rated health, ADLs, IADLs, depression, cognition, timed walk, number of days spent in bed, number of blocks walked, extremity strength, recent hospitalizations, feelings about life as a whole, and life satisfaction. We dichotomized variables into "healthy" or "sick," states, and estimated the prevalence of the healthy state and the probability of transitioning from one state to another, or dying, during yearly intervals. We compared men and women and three age groups (65-74, 75-84, and 85-94). Findings. Measures of successful aging showed similar results by gender. Most participants remained healthy even into advanced ages, although health declined for all measures. Recuperation, although less common with age, still occurred frequently. Men had a higher death rate than women regardless of health status, and were also more likely to remain in the healthy state. Discussion. The results suggest a qualitatively different experience of successful aging between men and women. Men did not simply "age faster" than women.
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http://dx.doi.org/10.1155/2012/243263DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3485538PMC
November 2012

Accommodation of missing data in supportive and palliative care clinical trials.

Curr Opin Support Palliat Care 2012 Dec;6(4):465-70

Fred Hutchinson Cancer Research Center, Seattle, Washington 98019, USA.

Purpose Of Review: Clinical trials to evaluate the supportive and palliative care treatments have some different missing data concerns than the other clinical trials. This study reviews the literature on missing data as it may apply to these trials.

Recent Findings: Prevention of missing data through study design and conduct is a recent area of focus. Missing data can be minimized by simplifying trial participation for patients, their caregivers, and trialists. Run-in periods with active drug or collecting data from observer (proxy) respondents may complicate a trial but may be used to address some specific concerns. Many analyses can accommodate data missing because of nonresponse by multiple imputation, using carefully chosen imputation models. Analysis of trials evaluating end-of-life care should distinguish between missing data and truncation because of death.

Summary: Likely patterns for missing data should be discussed when planning a clinical trial, as modifications to trial design can minimize missing data while still addressing study aims. Many statistical analysis methods are available to accommodate missing data, but robustness of study conclusions to assumptions about mechanisms underlying the missingness should be evaluated by sensitivity analyses.
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http://dx.doi.org/10.1097/SPC.0b013e328358441dDOI Listing
December 2012

Persistence and remission of musculoskeletal pain in community-dwelling older adults: results from the cardiovascular health study.

J Am Geriatr Soc 2012 Aug 2;60(8):1393-400. Epub 2012 Aug 2.

Department of Psychiatry, University of Washington, Seattle, Washington 98195, USA.

Objectives: To characterize longitudinal patterns of musculoskeletal pain in a community sample of older adults over a 6-year period and to identify factors associated with persistence of pain.

Design: Secondary analysis of the Cardiovascular Health Study.

Setting: Community-based cohort drawn from four U.S. counties.

Participants: Five thousand ninety-three men and women aged 65 and older.

Measurements: Over a 6-year period, pain was assessed each year using a single question about the presence of pain in any bones or joints during the last year. If affirmative, participants were queried about pain in seven locations (hands, shoulders, neck, back, hips, knees, feet). Participants were categorized according to the percentage of time that pain was present and according to the intermittent or chronic pattern of pain. Factors associated with persistent pain during five remaining years of the study were identified.

Results: Over 6 years, 32% of participants reported pain for three or more consecutive years, and 32% reported pain intermittently. Of those who reported pain the first year, 54% were pain free at least once during the follow-up period. Most of the pain at specific body locations was intermittent. Factors associated with remission of pain over 5 years included older age, male sex, better self-rated health, not being obese, taking fewer medications, and having fewer depressive symptoms. Approximately half of those with pain reported fewer pain locations the following year.

Conclusion: Musculoskeletal pain in older adults, despite high prevalence, is often intermittent. The findings refute the notion that pain is an inevitable, unremitting, or progressive consequence of aging.
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http://dx.doi.org/10.1111/j.1532-5415.2012.04082.xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3633775PMC
August 2012

Improving low-wage, midsized employers' health promotion practices: a randomized controlled trial.

Am J Prev Med 2012 Aug;43(2):125-33

Department of Health Services, University of Washington, Seattle, USA.

Background: The Guide to Community Preventive Services (Community Guide) offers evidence-based intervention strategies to prevent chronic disease. The American Cancer Society (ACS) and the University of Washington Health Promotion Research Center co-developed ACS Workplace Solutions (WPS) to improve workplaces' implementation of Community Guide strategies.

Purpose: To test the effectiveness of WPS for midsized employers in low-wage industries.

Design: Two-arm RCT; workplaces were randomized to receive WPS during the study (intervention group) or at the end of the study (delayed control group).

Setting/participants: Forty-eight midsized employers (100-999 workers) in King County WA.

Intervention: WPS provides employers one-on-one consulting with an ACS interventionist via three meetings at the workplace. The interventionist recommends best practices to adopt based on the workplace's current practices, provides implementation toolkits for the best practices the employer chooses to adopt, conducts a follow-up visit at 6 months, and provides technical assistance.

Main Outcome Measures: Employers' implementation of 16 best practices (in the categories of insurance benefits, health-related policies, programs, tracking, and health communications) at baseline (June 2007-June 2008) and 15-month follow-up (October 2008-December 2009). Data were analyzed in 2010-2011.

Results: Intervention employers demonstrated greater improvement from baseline than control employers in two of the five best-practice categories; implementing policies (baseline scores: 39% program, 43% control; follow-up scores: 49% program, 45% control; p=0.013) and communications (baseline scores: 42% program, 44% control; follow-up scores: 76% program, 55% control; p=0.007). Total best-practice implementation improvement did not differ between study groups (baseline scores: 32% intervention, 37% control; follow-up scores: 39% intervention, 42% control; p=0.328).

Conclusions: WPS improved employers' health-related policies and communications but did not improve insurance benefits design, programs, or tracking. Many employers were unable to modify insurance benefits and reported that the time and costs of implementing best practices were major barriers.

Trial Registration: This study is registered at clinicaltrials.gov NCT00452816.
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http://dx.doi.org/10.1016/j.amepre.2012.04.014DOI Listing
August 2012

Comparing years of healthy life, measured in 16 ways, for normal weight and overweight older adults.

J Obes 2012 20;2012:894894. Epub 2012 Jun 20.

Department of Biostatistics, University of Washington, Seattle, WA 98195, USA.

Introduction. The traditional definitions of overweight and obesity are not age specific, even though the relationship of weight to mortality is different for older adults. Effects of adiposity on aspects of health beside mortality have not been well investigated. Methods. We calculated the number of years of healthy life (YHL) in the 10 years after baseline, for 5,747 older adults. YHL was defined in 16 different ways. We compared Normal and Overweight persons, classified either by body mass index (BMI) or by waist circumference (WC). Findings. YHL for Normal and Overweight persons differed significantly in 25% of the comparisons, of which half favored the Overweight. Measures of physical health favored Normal weight, while measures of mental health and quality of life favored Overweight. Overweight was less favorable when defined by WC than by BMI. Obese persons usually had worse outcomes. Discussion. Overweight older adults averaged as many years of life and years of healthy life as those of Normal weight. There may be no outcome based reason to distinguish Normal from Overweight for older adults. Conclusion. The "Overweight paradox" appears to hold for nonmortality outcomes. New adiposity standards are needed for older adults, possibly different by race and sex.
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http://dx.doi.org/10.1155/2012/894894DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3388309PMC
August 2012

Comparison of 7-day recall and daily diary reports of COPD symptoms and impacts.

Value Health 2012 May 9;15(3):466-74. Epub 2012 Feb 9.

Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, NY 10065, USA.

Objective: Patient reporting of symptoms in a questionnaire with a 7-day recall period was expected to differ from symptom reporting in a 7-day symptom diary on the basis of cognitive theory of memory processes and several studies of symptoms and health behaviors.

Methods: A total of 101 adults with chronic obstructive pulmonary disease (COPD) completed a daily diary of items measuring symptoms and impacts of COPD for 7 days, and on the seventh day they completed a questionnaire of the same items with a 7-day recall period. The analysis examined concordance of 7-day recall with summary descriptors of the daily responses, examined the magnitude and covariates (patient characteristics and response patterns) of the difference between 7-day recall and mean of daily responses, and compared the discriminant ability and ability to detect change of 7-day recall and mean of daily responses.

Results: A 7-day recall was moderately concordant with the mean and maximum of daily responses and was 0.34 to 0.50 SDs higher than the mean of daily responses. Only the weekly report itself was a covariate of the difference. The discriminant ability and ability to detect change were equivalent.

Conclusions: In measuring the weeklong experience of COPD symptoms and impacts on groups of patients, the 7-day recall scores were higher than the daily diary scores, but equivalent in detecting change over time.
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http://dx.doi.org/10.1016/j.jval.2011.12.005DOI Listing
May 2012

A randomized trial to improve communication about end-of-life care among patients with COPD.

Chest 2012 Mar 22;141(3):726-735. Epub 2011 Sep 22.

Department of Medicine, University of Washington, Seattle, WA.

Objective: Patients with COPD consistently express a desire to discuss end-of-life care with clinicians, but these discussions rarely occur. We assessed whether an intervention using patient-specific feedback about preferences for discussing end-of-life care would improve the occurrence and quality of communication between patients with COPD and their clinicians.

Methods: We performed a cluster-randomized trial of clinicians and patients from the outpatient clinics at the Veterans Affairs Puget Sound Health Care System. Using self-reported questionnaires, we assessed patients' preferences for communication, life-sustaining therapy, and experiences at the end of life. The intervention clinicians and patients received a one-page patient-specific feedback form, based on questionnaire responses, to stimulate conversations. The control group completed questionnaires but did not receive feedback. Patient-reported occurrence and quality of end-of-life communication (QOC) were assessed within 2 weeks of a targeted visit. Intention-to-treat regression analyses were performed with generalized estimating equations to account for clustering of patients within clinicians.

Results: Ninety-two clinicians contributed 376 patients. Patients in the intervention arm reported nearly a threefold higher rate of discussions about end-of-life care (unadjusted, 30% vs 11%; P < .001). Baseline end-of-life communication was poor (intervention group QOC score, 23.3; 95% CI, 19.9-26.8; control QOC score, 19.2; 95% CI, 15.9-22.4). Patients in the intervention arm reported higher-quality end-of-life communication that was statistically significant, although the overall improvement was small (Cohen effect size, 0.21).

Conclusions: A one-page patient-specific feedback form about preferences for end-of-life care and communication improved the occurrence and quality of communication from patients' perspectives.

Trial Registry: ClinicalTrials.gov; No.: NCT00106080; URL: www.clinicaltrials.gov.
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http://dx.doi.org/10.1378/chest.11-0362DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3415164PMC
March 2012

Collaborative care intervention for stable ischemic heart disease.

Arch Intern Med 2011 Sep;171(16):1471-9

Departments of Medicine, University of Washington, Seattle, USA.

Background: Accumulating evidence suggests that collaborative models of care enhance communication among primary care providers, improving quality of care and outcomes for patients with chronic conditions. We sought to determine whether a multifaceted intervention that used a collaborative care model and was directed through primary care providers would improve symptoms of angina, self-perceived health, and concordance with practice guidelines for managing chronic stable angina.

Methods: We conducted a prospective trial, cluster randomized by provider, involving patients with symptomatic ischemic heart disease recruited from primary care clinics at 4 academically affiliated Department of Veterans Affairs health care systems. Primary end points were changes over 12 months in symptoms on the Seattle Angina Questionnaire, self-perceived health, and concordance with practice guidelines.

Results: In total, 183 primary care providers and 703 patients participated in the study. Providers accepted and implemented 91.6% of 701 recommendations made by collaborative care teams. Almost half were related to medications, including adjustments to β-blockers, long-acting nitrates, and statins. The intervention did not significantly improve symptoms of angina or self-perceived health, although end points favored collaborative care for 10 of 13 prespecified measures. While concordance with practice guidelines improved 4.5% more among patients receiving collaborative care than among those receiving usual care (P < .01), this was mainly because of increased use of diagnostic testing rather than increased use of recommended medications.

Conclusion: A collaborative care intervention was well accepted by primary care providers and modestly improved receipt of guideline-concordant care but not symptoms or self-perceived health in patients with stable angina.
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http://dx.doi.org/10.1001/archinternmed.2011.372DOI Listing
September 2011

Psychologic effects of automated external defibrillator training: a randomized trial.

Heart Lung 2011 Nov-Dec;40(6):502-10. Epub 2011 Mar 16.

Department of Health Services, University of Washington, Seattle, Washington 98195-7232, USA.

Objective: The objective of this study was to test whether an automated external defibrillator (AED) training program would positively affect the mental health of family members of high-risk patients.

Methods: A total of 305 patients with ischemic heart disease and their family members were randomized to 1 of 4 AED training programs: 2 video-based training programs and 2 face-to-face training programs that emphasized self-efficacy and perceived control. Patients and family members were surveyed at baseline and 3 and 9 months postischemic event on demographic characteristics, measures of quality of life (Short Form-36), self-efficacy, and perceived control. For this study, family members were the focus rather than the patients.

Results: Regression analyses showed that family members in the face-to-face training programs did not score better on any of the mental health status variables than family members who participated in the other training programs except for an increase in self-efficacy beliefs at 3 months after training.

Conclusion: The findings suggest that a specifically designed AED training program emphasizing self-efficacy and perceived control beliefs is not likely to enhance family member mental health.
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http://dx.doi.org/10.1016/j.hrtlng.2010.12.009DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3158282PMC
February 2012

Patterns and predictors of recovery from exhaustion in older adults: the cardiovascular health study.

J Am Geriatr Soc 2011 Feb 2;59(2):207-13. Epub 2011 Feb 2.

Center for the Study of Aging and Human Development, Duke University Medical Center, Durham, North Carolina, USA.

Objectives: To estimate the likelihood of, and factors associated with, recovery from exhaustion in older adults.

Design: Secondary analysis of a cohort study.

Setting: Six annual examinations in four U.S. communities.

Participants: Four thousand five hundred eighty-four men and women aged 69 and older.

Measurements: Exhaustion was considered present when a participant responded "a moderate amount" or "most of the time" to either of two questions: "How often have you had a hard time getting going?" and "How often does everything seem an effort?"

Results: Of the 964 participants who originally reported exhaustion, 634 (65.8%) were exhaustion free at least once during follow-up. When data from all time points were considered, 48% of those who reported exhaustion were exhaustion free the following year. After adjustment for age, sex, race, education, and marital status, 1-year recovery was less likely in individuals with worse self-rated health and in those who were taking six or more medications or were obese, depressed, or had musculoskeletal pain or history of stroke. In proportional hazards models, the following risk factors were associated with more persistent exhaustion over 5 years: poor self-rated health, six or more medications, obesity, and depression. Recovery was not less likely in participants with a history of cancer or heart disease.

Conclusion: Exhaustion is common in old age but is dynamic, even in those with a history of cancer and congestive heart failure. Recovery is especially likely in seniors who have a positive perception of their overall health, take few medications, and are not obese or depressed. These findings support the notion that resiliency is associated with physical and psychological well-being.
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http://dx.doi.org/10.1111/j.1532-5415.2010.03238.xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3059104PMC
February 2011

Social marketing, stages of change, and public health smoking interventions.

Health Educ Behav 2011 Apr 21;38(2):123-31. Epub 2011 Jan 21.

University of Washington, Seattle, WA 98195-7232, USA.

As a "thought experiment," the authors used a modified stages of change model for smoking to define homogeneous segments within various hypothetical populations. The authors then estimated the population effect of public health interventions that targeted the different segments. Under most assumptions, interventions that emphasized primary and secondary prevention, by targeting the Never Smoker, Maintenance, or Action segments, resulted in the highest nonsmoking life expectancy. This result is consistent with both social marketing and public health principles. Although the best thing for an individual smoker is to stop smoking, the greatest public health benefit is achieved by interventions that target nonsmokers.
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http://dx.doi.org/10.1177/1090198110369056DOI Listing
April 2011

Evaluating a preventive services index to adjust for healthy behaviors in observational studies of older adults.

Prev Chronic Dis 2010 Sep 15;7(5):A110. Epub 2010 Aug 15.

Health Promotion Research Center, School of Public Health, University of Washington, Seattle, WA 98105, USA.

Introduction: Analysis of outcome measures from nonrandomized, observational studies of people participating or not participating in health programs may be suspect because of selection bias. For example, fitness programs may preferentially enroll people who are already committed to healthy lifestyles, including use of preventive services. Some of our earlier studies have attempted to account for this potential bias by including an ad hoc preventive services index created from the patient's number of earlier clinical preventive services, to adjust for health-seeking behaviors. However, this index has not been validated. We formally evaluated the performance of this preventive services index by comparing it with its component parts and with an alternative index derived from principal component analysis by using the weighted sums of the principal components.

Methods: We used data from a cohort of 38,046 older adults. We used the following variables from the administrative database of a health maintenance organization to create this index: fecal occult blood test, flexible sigmoidoscopy, screening mammogram, prostate cancer screening, influenza vaccination, pneumococcal vaccination, and preventive care office visits.

Results: The preventive services index was positively correlated with each of the following components: colon cancer screening (r = .752), screening mammogram (r = .559), prostate cancer screening (r = .592), influenza vaccination (r = .844), pneumococcal vaccination (r = .487), and preventive care office visits (r = .737). An alternative preventive services index, created by using principal component analysis, had similar performance.

Conclusion: A preventive services index created by using administrative data has good face validity and construct validity and can be used to partially adjust for selection bias in observational studies of cost and use outcomes.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2938404PMC
September 2010

Physical activity and years of healthy life in older adults: results from the cardiovascular health study.

J Aging Phys Act 2010 Jul;18(3):313-34

Depts. of Medicine and Public Health Sciences, University of California, Davis, Medical Center, Sacramento, CA, USA.

Little is known about how many years of life and disability-free years seniors can gain through exercise. Using data from the Cardiovascular Health Study, the authors estimated the extra years of life and self-reported healthy life (over 11 years) and years without impairment in activities of daily living (over 6 years) associated with quintiles of physical activity (PA) in older adults from different age groups. They estimated PA from the Minnesota Leisure Time Activities Questionnaire. Multivariable linear regression adjusted for health-related covariates. The relative gains in survival and years of healthy life (YHL) generally were proportionate to the amount of PA, greater among those 75+, and higher in men. Compared with being sedentary, the most active men 75+ had 1.49 more YHL (95% CI: 0.79, 2.19), and the most active women 75+ had 1.06 more YHL (95% CI: 0.44, 1.68). Seniors over age 74 experience the largest relative gains in survival and healthy life from physical activity.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3978479PMC
http://dx.doi.org/10.1123/japa.18.3.313DOI Listing
July 2010

Health benefits of increased walking for sedentary, generally healthy older adults: using longitudinal data to approximate an intervention trial.

J Gerontol A Biol Sci Med Sci 2010 Sep 19;65(9):982-9. Epub 2010 May 19.

Department of Biostatistics, University of Washington, 1959 North East Pacific Avenue, Seattle, WA 9815-7232, USA.

Background: Older adults are often advised to walk more, but randomized trials have not conclusively established the benefits of walking in this age group. Typical analyses based on observational data may have biased results. Here, we propose a "limited-bias," more interpretable estimate of the health benefits to sedentary healthy older adults of walking more, using longitudinal data from the Cardiovascular Health Study.

Methods: The number of city blocks walked per week, collected annually, was classified as sedentary (<7 blocks per week), somewhat active, or active (>or=28). Analysis was restricted to persons sedentary and healthy in the first 2 years. In Year 3, some became more active (the treatment groups). Self-rated health at Year 5 (follow-up) was regressed on walking at Year 3, with additional covariates from Year 2, when all were sedentary.

Results: At follow-up, 83.5% of those active at baseline had excellent, very good, or good self-rated health, as compared with 63.9% of the sedentary, an apparent benefit of 19.6 percentage points. After covariate adjustment, the limited-bias estimate of the benefit was 11.2 percentage points (95% confidence interval 3.7-18.6). Ten different outcome measures showed a benefit, ranging from 5 to 11 percentage points. Estimates from other study designs were smaller, less interpretable, and potentially more biased.

Conclusions: In longitudinal studies where walking and health are ascertained at every wave, limited-bias estimates can provide better estimates of the benefits of walking. A surprisingly small increase in walking was associated with meaningful health benefits.
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http://dx.doi.org/10.1093/gerona/glq070DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2920578PMC
September 2010

Comparison of health care expenditures among insured users and nonusers of complementary and alternative medicine in Washington State: a cost minimization analysis.

J Altern Complement Med 2010 Apr;16(4):411-7

Department of Health Services, University of Washington, Seattle, WA, USA.

Objectives: The purpose of this analysis was to compare health care expenditures between insured patients with back pain, fibromyalgia syndrome, or menopause symptoms who used complementary and alternative medical (CAM) providers for some of their care to a matched group of patients who did not use any CAM care. Insurance coverage was equivalent for both conventional and CAM providers.

Design: Insurance claims data for 2000-2003 from Washington State, which mandates coverage of CAM providers, were analyzed. CAM-using patients were matched to CAM-nonusing patients based on age group, gender, index medical condition, overall disease burden, and prior-year expenditures.

Results: Both unadjusted tests and linear regression models indicated that CAM users had lower average expenditures than nonusers. (Unadjusted: $3,797 versus $4,153, p = 0.0001; beta from linear regression -$367 for CAM users.) CAM users had higher outpatient expenditures that which were offset by lower inpatient and imaging expenditures. The largest difference was seen in the patients with the heaviest disease burdens among whom CAM users averaged $1,420 less than nonusers, p < 0.0001, which more than offset slightly higher average expenditures of $158 among CAM users with lower disease burdens.

Conclusions: This analysis indicates that among insured patients with back pain, fibromyalgia, and menopause symptoms, after minimizing selection bias by matching patients who use CAM providers to those who do not, those who use CAM will have lower insurance expenditures than those who do not use CAM.
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http://dx.doi.org/10.1089/acm.2009.0261DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3110809PMC
April 2010

Prevalence, incidence, and persistence of major depressive symptoms in the Cardiovascular Health Study.

Aging Ment Health 2010 Mar;14(2):168-76

Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle 98195, USA.

Purpose: To explore the association of major depressive symptoms with advancing age, sex, and self-rated health among older adults.

Design And Methods: We analyzed 10 years of annual assessments in a longitudinal cohort of 5888 Medicare recipients in the Cardiovascular Health Study. Self-rated health was assessed with a single question, and subjects categorized as healthy or sick. Major depressive symptoms were assessed using the Center for Epidemiologic Studies Short Depression Scale, with subjects categorized as nondepressed (score < 10) or depressed (> or =10). Age-, sex-, and health-specific prevalence of depression and the probabilities of transition between depressed and nondepressed states were estimated.

Results: The prevalence of a major depressive state was higher in women, and increased with advancing age. The probability of becoming depressed increased with advancing age among the healthy but not the sick. Women showed a greater probability than men of becoming depressed, regardless of health status. Major depressive symptoms persisted over one-year intervals in about 60% of the healthy and 75% of the sick, with little difference between men and women.

Implications: Clinically significant depressive symptoms occur commonly in older adults, especially women, increase with advancing age, are associated with poor self-rated health, and are largely intransigent. In order to limit the deleterious consequences of depression among older adults, increased attention to prevention, screening, and treatment is warranted. A self-rated health item could be used in clinical settings to refine the prognosis of late-life depression.
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http://dx.doi.org/10.1080/13607860903046537DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3622544PMC
March 2010

Identification of ovarian cancer symptoms in health insurance claims data.

J Womens Health (Larchmt) 2010 Mar;19(3):381-9

Department of Biostatistics, School of Public Health, University of Washington, Seattle, Washington 98195-9455, USA.

Background: Women with ovarian cancer have reported abdominal/pelvic pain, bloating, difficulty eating or feeling full quickly, and urinary frequency/urgency prior to diagnosis. We explored these findings in a general population using a dataset of insured women aged 40-64 and investigated the potential effectiveness of a routine review of claims data as a prescreen to identify women at high risk for ovarian cancer.

Methods: Data from a large Washington State health insurer were merged with the Seattle-Puget Sound Surveillance, Epidemiology and End Results (SEER) cancer registry for 2000-2004. We estimated the prevalence of symptoms in the 36 months prior to diagnosis for early and late-stage ovarian cancer cases and for two comparison groups. The potential performance of a passive screener that would flag women with two or more visits for any of the symptoms in the previous 2-month period was examined.

Results: Of the 223,903 insured women, 161 had incident cases of ovarian cancer. Both early and late-stage patients had a higher prevalence of abdominal/pelvic pain and bloating than the comparison groups, primarily in the 3 months before diagnosis. The passive screener had a sensitivity of 0.31 and specificity of 0.83 and usually identified women right before diagnosis. Assuming an average cost of $500 per false positive, the screener would be considered cost-effective if the true positives had an average increase of 8.5 years of life expectancy.

Conclusions: These results support previous findings that ovarian cancer symptoms were reported in health insurance claims and were more prevalent before diagnosis, but the symptoms may occur too close to the diagnosis date to provide useful diagnostic information. The passive screening approach should be reevaluated in the future using electronic medical records; if found to be effective, the method may be potentially useful for other incident diseases.
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http://dx.doi.org/10.1089/jwh.2009.1550DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2867625PMC
March 2010

Joint modeling of self-rated health and changes in physical functioning.

J Am Stat Assoc 2009 Sep;104(487):912

Group Health Center for Health Studies, 1730 Minor Ave., Suite 1600, Seattle, WA, 98101, USA.

Self-rated health is an important indicator of future morbidity and mortality. Past research has indicated that self-rated health is related to both levels of and changes in physical functioning. However, no previous study has jointly modeled longitudinal functional status and self-rated health trajectories. We propose a joint model for self-rated health and physical functioning that describes the relationship between perceptions of health and the rate of change of physical functioning or disability. Our joint model uses a non-homogeneous Markov process for discrete physical functioning states and connects this to a logistic regression model for "healthy" versus "unhealthy" self-rated health through parameters of the physical functioning model. We use simulation studies to establish finite sample properties of our estimators and show that this model is robust to misspecification of the functional form of the relationship between self-rated health and rate of change of physical functioning. We also show that our joint model performs better than an empirical model based on observed changes in functional status. We apply our joint model to data from the Cardiovascular Health Study (CHS), a large, multi-center, longitudinal study of older adults. Our analysis indicates that self-rated health is associated both with level of functioning as indicated by difficulty with activities of daily living (ADL) and instrumental activities of daily living (IADL), and the risk of increasing difficulty with ADLs and IADLs.
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http://dx.doi.org/10.1198/jasa.2009.ap08423DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2819480PMC
September 2009

Longitudinal Data with Follow-up Truncated by Death: Match the Analysis Method to Research Aims.

Stat Sci 2009 ;24(2):211

Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109, U.S.A. (206) 667-2804,

Diverse analysis approaches have been proposed to distinguish data missing due to death from nonresponse, and to summarize trajectories of longitudinal data truncated by death. We demonstrate how these analysis approaches arise from factorizations of the distribution of longitudinal data and survival information. Models are illustrated using cognitive functioning data for older adults. For unconditional models, deaths do not occur, deaths are independent of the longitudinal response, or the unconditional longitudinal response is averaged over the survival distribution. Unconditional models, such as random effects models fit to unbalanced data, may implicitly impute data beyond the time of death. Fully conditional models stratify the longitudinal response trajectory by time of death. Fully conditional models are effective for describing individual trajectories, in terms of either aging (age, or years from baseline) or dying (years from death). Causal models (principal stratification) as currently applied are fully conditional models, since group differences at one timepoint are described for a cohort that will survive past a later timepoint. Partly conditional models summarize the longitudinal response in the dynamic cohort of survivors. Partly conditional models are serial cross-sectional snapshots of the response, reflecting the average response in survivors at a given timepoint rather than individual trajectories. Joint models of survival and longitudinal response describe the evolving health status of the entire cohort. Researchers using longitudinal data should consider which method of accommodating deaths is consistent with research aims, and use analysis methods accordingly.
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http://dx.doi.org/10.1214/09-STS293DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2812934PMC
January 2009

Might massage or guided meditation provide "means to a better end"? Primary outcomes from an efficacy trial with patients at the end of life.

J Palliat Care 2009 ;25(2):100-8

Division of Pulmonary and Critical Care Medicine, Department of Medicine, School of Medicine, University of Washington, Seattle, Washington, USA.

This article reports findings from a randomized controlled trial of massage and guided meditation with patients at the end of life. Using data from 167 randomized patients, the authors considered patient outcomes through 10 weeks post-enrollment, as well as next-of-kin ratings of the quality of the final week of life for 106 patients who died during study participation. Multiple regression models demonstrated no significant treatment effects of either massage or guided meditation, delivered up to twice a week, when compared with outcomes of an active control group that received visits from hospice-trained volunteers on a schedule similar to that of the active treatment arms. The authors discuss the implications of their findings for integration of these complementary and alternative medicine therapies into standard hospice care.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2858762PMC
September 2009

Chiropractic use by urban and rural residents with insurance coverage.

J Rural Health 2009 ;25(3):253-8

Department of Health Services, University of Washington, Seattle, Washington, USA.

Purpose: To describe the use of chiropractic care by urban and rural residents in Washington state with musculoskeletal diagnoses, all of whom have insurance coverage for this care. The analyses investigate whether restricting the analyses to insured individuals attenuates previously reported differences in the prevalence of chiropractic use between urban and rural residents as well as whether differences in provider availability or patient cost-sharing explain the difference in utilization.

Methods: Claims data from 237,500 claimants in 2 large insurance companies in Washington state for calendar year 2002 were analyzed, using adjusted clinical group risk adjustment for differences in disease burden and rural urban commuting area codes for rurality definition.

Findings: The proportion of claimants using chiropractors was higher in rural than urban residents (44% vs 32%, P < .001). Lack of conventional providers in rural areas did not completely explain this difference, nor did differences in patient cost-sharing or demographics. Among those who used chiropractors, those in urban areas had more chiropractic visits than users of chiropractic in rural areas.

Conclusions: Among insured adults, use of chiropractic care was higher in rural than in urban areas. Reasons suggested for this difference in previous reports were not borne out in this data set.
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http://dx.doi.org/10.1111/j.1748-0361.2009.00227.xDOI Listing
September 2009
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