Transforming self-rated health and the SF-36 scales to include death and improve interpretability

Effect of a Community Health Worker-Led Intervention Among Low-Income and Minoritized Patients With Cancer: A Randomized Clinical Trial

PURPOSE

To determine whether a community health worker (CHW)-led intervention could improve health-related quality of life (HRQoL; primary outcome) more than usual care among low-income and racial and ethnic minoritized populations newly diagnosed with cancer.

METHODS

This randomized clinical trial was conducted from November 1, 2018, until August 31, 2021, in outpatient cancer clinics in Atlantic City, NJ, and Chicago, IL. Hourly low-wage worker members of an employer union health fund age 18 years or older with newly diagnosed solid tumor and hematologic malignancies were randomly assigned 1:1 to usual care (control group) or usual care augmented with a trained CHW for 12 months (intervention group). The CHW assisted participants with advance care planning (ACP), proactively screened symptoms, and referred participants to community-based resources for identified health-related social needs. Usual care comprised nurse case management and benefits redesign (waived copayments and free transportation for any cancer care received at preferred oncology clinics in each city). The primary outcome was HRQoL. Secondary outcomes included patient activation, satisfaction with decision, ACP documentation, health care use, total health care costs, and overall survival.

RESULTS

A total of 160 participants were enrolled. Intervention group participants had a greater increase in mean HRQoL scores at 4-month and 12-month follow-up as compared with baseline than control group participants (expected mean difference, 11.25 [95% CI, 7.28 to 15.22]; 11.29 [95% CI, 6.96 to 15.62], respectively).

CONCLUSION

In this randomized trial, a CHW-led intervention significantly improved HRQoL for low-income and racial and ethnic minoritized patients with cancer more than usual care alone.

Impact of a specialized oral nutritional supplement on quality of life in older adults following hospitalization: Post-hoc analysis of the NOURISH trial

BACKGROUND & AIMS

Both during and after hospitalization, nutritional care with daily intake of oral nutritional supplements (ONS) improves health outcomes and decreases risk of mortality in malnourished older adults. In a post-hoc analysis of data from hospitalized older adults with malnutrition risk, we sought to determine whether consuming a specialized ONS (S-ONS) containing high protein and beta-hydroxy-beta-methylbutyrate (HMB) can also improve Quality of Life (QoL).

METHODS

We analyzed data from the NOURISH trial-a randomized, placebo-controlled, multi-center, double-blind study conducted in patients with congestive heart failure, acute myocardial infarction, pneumonia, or chronic obstructive pulmonary disease. Patients received standard care + S-ONS or placebo beverage (target 2 servings/day) during hospitalization and for 90 days post-discharge. SF-36 and EQ-5D QoL outcomes were assessed at 0-, 30-, 60-, and 90-days post-discharge. To account for the missing QoL observations (27.7%) due to patient dropout, we used multiple imputation. Data represent differences between least squares mean (LSM) values with 95% Confidence Intervals for groups receiving S-ONS or placebo treatments.

RESULTS

The study population consisted of 622 patients of mean age ±standard deviation: 77.9 ± 8.4 years and of whom 52.1% were females. Patients consuming placebo had lower (worse) QoL domain scores than did those consuming S-ONS. Specifically for the SF-36 health domain scores, group differences (placebo vs S-ONS) in LSM were significant for the mental component summary at day 90 (-4.23 [-7.75, -0.71]; p = 0.019), the domains of mental health at days 60 (-3.76 [-7.40, -0.12]; p = 0.043) and 90 (-4.88 [-8.41, -1.34]; p = 0.007), vitality at day 90 (-3.33 [-6.65, -0.01]; p = 0.049) and social functioning at day 90 (-4.02 [-7.48,-0.55]; p = 0.023). Compared to placebo, differences in LSM values for the SF-36 general health domain were significant with improvement in the S-ONS group at hospital discharge and beyond: day 0 (-2.72 [-5.33, -0.11]; p = 0.041), day 30 (-3.08 [-6.09, -0.08]; p = 0.044), day 60 (-3.95 [-7.13, -0.76]; p = 0.015), and day 90 (-4.56 [-7.74, -1.38]; p = 0.005).

CONCLUSIONS

In hospitalized older adults with cardiopulmonary diseases and evidence of poor nutritional status, daily intake of S-ONS compared to placebo improved post-discharge QoL scores for mental health/cognition, vitality, social functioning, and general health. These QoL benefits complement survival benefits found in the original NOURISH trial analysis.

CLINICAL TRIAL REGISTRATION

NCT01626742.

Prediction of physical functioning and general health status trajectories on mortality among persons with cognitive impairment

BACKGROUND

The concern posed by the confluence of aging and cognitive impairment is growing in importance as the U.S. population rapidly ages. As such, we sought to examine the predictive power of physical functioning (PF) and general health status (GHS) trajectories on mortality outcomes among persons with cognitive impairment (PCIs).

METHODS

We used group-based trajectory models to identify latent group memberships for PF trajectories in 1,641 PCIs and GHS trajectories in 2,021 PCIs from the National Health and Aging Trends Survey (2011-2018) and applied logistic regressions to predict mortality using these memberships controlling for individual characteristics.

RESULTS

We identified six trajectory groups for PF and four groups for GHS. Trajectory group memberships for both outcomes significantly predicted mortality. For PF, group memberships largely captured the average levels over time, and worse trajectories (i.e., lower baselines and faster declines) were associated with higher odds of death. The highest mortality risk was associated with the group experiencing a sharp decline early in its PF trajectory, although its average level across time was not the lowest. For GHS, we observed two groups with comparable average levels across time, but the one with a convex-shape trajectory had much higher mortality risks compared to the one with a concave-shape trajectory.

CONCLUSIONS

Our findings highlighted that health trajectories predicted mortality among PCIs, not only because of general levels but also because of the shapes of declines. Close monitoring health deterioration of PCIs is crucial to understand the health burden of this population and to make subsequent actions.

Comprehensive approach to reintegration of disability benefit recipients with multiple problems (CARm) into the labour market: results of a randomized controlled trial

PURPOSE

Although most clients on work disability benefits face multiple problems, most traditional interventions for (re)integration focus on a single problem. The aim of this study was to evaluate the "Comprehensive Approach to Reintegrate clients with multiple problems" (CARm), which provides a strategy for labour experts to build a relationship with each client in order to support clients in their needs and mobilize their social networks.

METHODS

This study is a stratified, two-armed, non-blinded randomized controlled trial (RCT), with a 12-month follow-up period. Outcome measures were: having paid work, level of functioning, general health, quality of life, and social support.

RESULTS

We included a total of 207 clients in our study; 97 in the intervention group and 110 in the care as usual (CAU) group. The clients' mean age was 35.4 years (SD 12.8), 53.1% were female, and 179 (86.5%) reported multiple problems. We found the CARm intervention to have no significant effects superior to those of the CAU group on all outcomes.

CONCLUSION

As we found no superior effect of the CARm intervention compared to CAU, we cannot recommend widespread adoption of CARm. A process evaluation will give more insight into possible implementation failure of the intervention. IMPLICATIONS FOR REHABILITATIONMost traditional interventions for (re)integration into the labour market are problem-centred, i.e., focusing on a single problem, and have limited effectiveness in persons with multiple problems.A strength-based intervention may be suitable for vocational rehabilitation and disability settings, since it contains many elements (e.g., being strength-based, focused on clients' wishes and goals, and involving activation of the social environment) also likely to improve chances of re-employment of persons with multiple problems.In this study a strength-based intervention did not show a superior effect on paid employment and functioning within one year follow-up compared to care as usual in people with multiple problems on a work disability benefit.

Trajectories of General Health Status and Depressive Symptoms Among Persons With Cognitive Impairment in the United States

ObjectivesTo identify and examine heterogeneous trajectories of general health status (GHS) and depressive symptoms (DS) among persons with cognitive impairment (PCIs). Methods: We use group-based trajectory models to study 2361 PCIs for GHS and 1927 PCIs for DS from the National Health and Aging Trends Survey 2011-2018, and apply multinomial logistic regressions to predict identified latent trajectory group memberships using individual characteristics. Results: For both GHS and DS, there were six groups of PCIs with distinct trajectories over a 7-year period. More than 40% PCIs experienced sharp declines in GHS, and 35.5% experienced persistently poor GHS. There was greater heterogeneity in DS trajectories with 55% PCIs experiencing improvement, 16.4% experiencing persistently high DS, and 30.5% experiencing deterioration. Discussion: The GHS trajectories illustrate the heavy burden of poor and declining health among PCIs. Further research is needed to understand the factors underlying stable or improving DS despite declining GHS.

A structured methodology review showed analyses of functional outcomes are frequently limited to "survivors only" in trials enrolling patients at high risk of death

OBJECTIVE

This structured methodology review evaluated statistical approaches used in randomized controlled trials (RCTs) enrolling patients at high risk of death and makes recommendations for reporting future RCTs.

STUDY DESIGN AND SETTING

Using PubMed, we searched for RCTs published in five general medicine journals from January 2014 to August 2019 wherein mortality was ≥10% in at least one randomized group. We abstracted primary and secondary outcomes, statistical analysis methods, and patient samples evaluated (all randomized patients vs. "survivors only").

RESULTS

Of 1947 RCTs identified, 434 met eligibility criteria. Of the eligible RCTs, 91 (21%) and 351 (81%) had a primary or secondary functional outcome, respectively, of which 36 (40%) and 263 (75%) evaluated treatment effects among "survivors only". In RCTs that analyzed all randomized patients, the most common methods included use of ordinal outcomes (e.g., modified Rankin Scale) or creating composite outcomes (primary: 41 of 91 [45%]; secondary: 57 of 351 [16%]).

CONCLUSION

In RCTs enrolling patients at high risk of death, statistical analyses of functional outcomes are frequently conducted among "survivors only," for which conclusions might be misleading. Given the growing number of RCTs conducted among patients hospitalized with COVID-19 and other critical illnesses, standards for reporting should be created.

Opioid and Other Medication Use and General Health Status in a Cohort of Older Adults

OBJECTIVE

The aim of this study was to determine whether the use of opioids and other medications in a cohort of older adults was associated with self-reported health status.

METHODS

Among participants in the Prostate, Lung, Colorectal, and Ovarian (PLCO) Screening Trial linked to Medicare Part D claims data and answering a quality-of-life questionnaire, we examined the relationship between medication use over a 5-year period and various self-reported health status variables assessed several years later, including overall health status (STATUS) and trouble with activities of daily living (TADL). Multivariable logistic regression was used to estimate odds ratios (ORs) for the health status variables and metrics of medication use, including >60-day use, and for opiates, chronic use, with models controlling for demographics (model I), additionally for chronic conditions (model II), and additionally for other medication use (model III).

RESULTS

The study cohort included 22,844 PLCO participants (56% women, 90% non-Hispanic whites); 4.2% had chronic opioid use and 12.5% used for >60 days. Fair-poor STATUS was reported in 37.9% of participants with chronic opioid use versus 15.0% of participants without (p < 0.001). ORs for chronic opioid use for fair-poor STATUS (compared to good-excellent) were significantly elevated in all models but decreased from model I (OR = 3.6; 95% CI :3.1-4.1) to model II (OR = 2.7; 95% CI :2.3-3.1) to model III (OR = 2.1; 95% CI :1.8-2.5). ORs for TADL were generally similar to those for STATUS. Other drug classes also had significantly elevated model III ORs for fair-poor versus good-excellent STATUS (range 1.1-1.6).

CONCLUSION

Frequent use of various medication classes correlated with measures of future health status in an elderly population, with opioids having the strongest association. The magnitude of the association decreased after controlling for concurrent chronic conditions but remained elevated. Future research should consider how the use of opioids and other medications impact measures of health-related quality of life.

idem: An R Package for Inferences in Clinical Trials with Death and Missingness

In randomized controlled trials of seriously ill patients, death is common and often defined as the primary endpoint. Increasingly, non-mortality outcomes such as functional outcomes are co-primary or secondary endpoints. Functional outcomes are not defined for patients who die, referred to as "truncation due to death", and among survivors, functional outcomes are often unobserved due to missed clinic visits or loss to follow-up. It is well known that if the functional outcomes "truncated due to death" or missing are handled inappropriately, treatment effect estimation can be biased. In this paper, we describe the package idem that implements a procedure for comparing treatments that is based on a composite endpoint of mortality and the functional outcome among survivors. Among survivors, the procedure incorporates a missing data imputation procedure with a sensitivity analysis strategy. A web-based graphical user interface is provided in the idem package to facilitate users conducting the proposed analysis in an interactive and user-friendly manner. We demonstrate idem using data from a recent trial of sedation interruption among mechanically ventilated patients.

Association Between Self-rated Health, Coronary Artery Calcium Scores, and Atherosclerotic Cardiovascular Disease Risk: The Multi-Ethnic Study of Atherosclerosis (MESA)

IMPORTANCE

The interplay of self-rated health (SRH), coronary artery calcium (CAC) scores, and cardiovascular risk is poorly described.

OBJECTIVES

To assess the degree of correlation between SRH and CAC, to determine whether these measures are complementary for risk prediction, and to assess the incremental value of the addition of SRH to established risk tools.

DESIGN, SETTING, AND PARTICIPANTS

The Multi-Ethnic Study of Atherosclerosis (MESA) is a large population-based prospective cohort study of adults aged 45 to 84 years who were recruited from 6 US communities. A total of 6764 participants without baseline cardiovascular disease (CVD) were included in the analysis. Data were collected from July 2000 through August 2002. Follow-up was completed by December 2013, and data were analyzed from October 2018 to December 2018.

EXPOSURES

The EVGGFP (excellent, very good, good, fair, and poor) self-assessment of overall health (assessed before the baseline study examination) and CAC score. The EVGGFP rating was categorized as poor/fair, good, very good, or excellent.

MAIN OUTCOMES AND MEASURES

Hard coronary heart disease (CHD) events, hard CVD events, and all-cause mortality during a median follow-up of 13.2 years (interquartile range, 12.7-13.7 years).

RESULTS

Among the study population of 6764 participants, the mean (SD) age was 62.1 (10.2) years, and 52.9% were women. The EVGGFP rating was strongly associated with age, sex, race/ethnicity, educational and income levels, healthy diet and physical activity, and cardiovascular risk factors. Despite encapsulating many risk variables, no correlation (r = -0.007; P = .57) or association between EVGGFP and the presence (χ2 = 0.84; P = .84) or severity (χ2 = 4.64; P = .86) of CAC was found. During follow-up, 1161 deaths, 637 hard CVD events, and 405 hard CHD events were recorded. In models adjusted for age, sex, race/ethnicity, and CAC, participants who reported excellent health had a 45% lower risk of CVD (hazard ratio [HR], 0.55; 95% CI, 0.39-0.77) and a 42% lower risk of CHD (HR, 0.58; 95% CI, 0.37-0.90) compared with those who reported poor/fair health. Participants in the excellent SRH category who had any CAC had markedly elevated risk of hard CHD (HR, 6.19; 95% CI, 2.1-18.3) and CVD (HR, 6.50; 95% CI, 2.7-15.6) events compared with those with a CAC score of 0. The addition of the EVGGFP rating to CAC improved the area under the curve (C statistic) for CHD events (0.725 vs 0.734; P = .007), CVD events (0.693 vs 0.706; P < .001), and all-cause mortality (0.685 vs 0.707; P < .001). However, the addition of the EVGGFP rating to the combination of CAC and atherosclerotic CVD risk score did not significantly improve C statistics for CHD events (0.751 vs 0.753; P = .39), CVD events (0.739 vs 0.741; P = .18), or all-cause mortality (0.779 vs 0.781; P = .13).

CONCLUSIONS AND RELEVANCE

Although SRH and CAC integrate many risk variables, this study suggests that they are poorly correlated and have complementary predictive utility. A perception of excellent health does not obviate the need for definitive assessment of CVD risk, whereas fair/poor perceived health may serve as a risk enhancer, arguing for advanced risk assessment in selected clinical scenarios.

Self-Rated Health as a Predictor of Death after Two Years: The Importance of Physical and Mental Wellbeing Postintensive Care

INTRODUCTION

The objective of this study is, among half-year intensive care survivors, to determine whether self-assessment of health can predict two-year mortality.

METHODS

The study is a prospective cohort study based on the Procalcitonin and Survival Study trial. Half-year survivors from this 1200-patient multicenter intensive care trial were sent the SF-36 questionnaire. We used both a simple one-item question and multiple questions summarized as a Physical Component Summary (PCS) and a Mental Component Summary (MCS) score. The responders were followed for vital status 730 days after inclusion. Answers were dichotomized into a low-risk and a high-risk group and hazard ratios (HR) with 95% confidence interval (CI) were calculated by Cox proportional hazard analyses.

CONCLUSION

We found that self-rated health measured by a single question was a strong independent predictor of two-year all-cause mortality (HR: 1.8; 95% CI: 1.1-3.0). The multi-item component scores of the SF-36 also predicted two-year mortality (PCS: HR: 2.9; 95% CI 1.7-5.0) (MCS: HR: 1.9; 95% CI 1.1-3.4). These results suggest that self-rated health questions could help in identifying patients at excess risk. Randomized controlled trials are needed to test whether our findings represent causality.

Effects of Disease Burden and Functional Adaptation on Morbidity and Mortality on Older Adults

OBJECTIVES

To ascertain whether older adults with extensive disease but relative vigor (adapters) shorten the period at the end of life in which they live with morbidity (compress morbidity).

DESIGN

Prospective, community-based cohort study in four U.S. cities.

SETTING

Cardiovascular Health Study.

PARTICIPANTS

Individuals aged 65 and older.

MEASUREMENTS

Participants were categorized into three groups according to extent of disease (assessed noninvasively), vigor, and frailty (expected agers (n = 3,528, extent of disease similar to vigor and frailty-reference group), adapters (n = 882, higher disease but vigorous), and prematurely frail (n = 855, lower disease but frail)) and compared according to years of able life (YAL), years of self-reported healthy life (YHL), and mortality using multivariable regression and survival analysis.

RESULTS

After adjustment, adapters had 0.97 (95% confidence interval (CI) = 0.60-1.33) more YAL and 0.54 (95% CI = 0.19-0.90) more YHL than expected agers, and those who were prematurely frail had -0.99 (95% CI = -1.36 to -0.62) fewer YAL and -0.53 (95% CI = -0.89 to -0.17) fewer YHL than expected agers. Adapters had 0.9 more and prematurely frail had 1.5 fewer years of total life than expected agers (P < .001). Adapters spent 55% of their remaining life able and healthy, those who were prematurely frail spent 37%, and of expected agers spent 47% (P < .001).

CONCLUSION

Despite similar levels of disease burden, older adults who were more vigorous appeared to compress morbidity and live longer. Older adults with higher frailty lengthened morbidity and had greater mortality. Adaptive factors may compress morbidity and decrease mortality.

Inference in randomized trials with death and missingness

In randomized studies involving severely ill patients, functional outcomes are often unobserved due to missed clinic visits, premature withdrawal, or death. It is well known that if these unobserved functional outcomes are not handled properly, biased treatment comparisons can be produced. In this article, we propose a procedure for comparing treatments that is based on a composite endpoint that combines information on both the functional outcome and survival. We further propose a missing data imputation scheme and sensitivity analysis strategy to handle the unobserved functional outcomes not due to death. Illustrations of the proposed method are given by analyzing data from a recent non-small cell lung cancer clinical trial and a recent trial of sedation interruption among mechanically ventilated patients.

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

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.

Effects of a DXA result letter on satisfaction, quality of life, and osteoporosis knowledge: a randomized controlled trial

Background

Undiagnosed, or diagnosed and untreated osteoporosis (OP) increases the likelihood that falls result in hip fractures, decreased quality of life (QOL), and significant medical expenditures among older adults. We tested whether a tailored dual energy x-ray absorptiometry (DXA) test result letter and an accompanying educational bone-health brochure affected patient satisfaction, QOL, or OP knowledge.

Methods

The Patient Activation after DXA Result Notification (PAADRN) study was a double-blinded, pragmatic, randomized trial which enrolled patients from 2012 to 2014. We randomized 7,749 patients presenting for DXA at three health care institutions in the United States who were ≥ 50 years old and able to understand English. Intervention patients received a tailored letter four weeks after DXA containing their results, 10-year fracture risk, and a bone-health educational brochure. Control patients received the results of their DXA per the usual practices of their providers and institutions. Satisfaction with bone health care, QOL, and OP knowledge were assessed at baseline and 12- and 52-weeks after DXA. Intention-to-treat analyses used multiple imputation for missing data and random effects regression models to adjust for clustering within providers and covariates.

Results

At 12-weeks 6,728 (86.8 %) and at 52-weeks 6,103 participants (78.8 %) completed their follow-up interviews. The intervention group was more satisfied with their bone health care compared to the usual care group at both their 12- and 52-week follow-ups (standardized effect size = 0.28 at 12-weeks and 0.17 at 52-weeks, p < 0.001). There were no differences between the intervention and usual care groups in QOL or OP knowledge at either time point.

Conclusions

A tailored DXA result letter and bone-health educational brochure sent to patients improved patient satisfaction with bone-related health care.

Trial registration

Clinical Trials.gov Identifier: NCT01507662 First received: December 8, 2011.

Best (but oft-forgotten) practices: expressing and interpreting associations and effect sizes in clinical outcome assessments

This article reviews methods used to facilitate the interpretation and evaluation of group-level differences in clinical outcome assessments. These methods complement and supplement tests of statistical significance. Examples, including studies in nutrition, are used to illustrate the application of the interpretation methods for group-level comparisons from experimental or observational studies. In addition, specific pitfalls of evaluating change in meta-analysis studies are described. A set of recommendations is provided. This review is intended as an introduction for the novice and as a refresher for the experienced researcher.

Best (but oft-forgotten) practices: expressing and interpreting associations and effect sizes in clinical outcome assessments

This article reviews methods used to facilitate the interpretation and evaluation of group-level differences in clinical outcome assessments. These methods complement and supplement tests of statistical significance. Examples, including studies in nutrition, are used to illustrate the application of the interpretation methods for group-level comparisons from experimental or observational studies. In addition, specific pitfalls of evaluating change in meta-analysis studies are described. A set of recommendations is provided. This review is intended as an introduction for the novice and as a refresher for the experienced researcher.

Changes in Self-Rated Health During the Transition to Retiring Living Among Medicare Managed-Care Recipients

Objectives

Moving into a retirement community may be precipitated by or bring about changes in health status. We hypothesized that moving into a retirement community would be associated with a decline in self-rated health (SRH), but that health-related factors would mitigate this association.

Methods

We analyzed data from 58,272 participants in Cohort 3 of the Medicare Health Outcome Survey. Individuals answered questions regarding living status in 2000 and 2002. Those who moved into a retirement community were compared with those who did not. The primary outcome was change in SRH. We created adjusted and unadjusted models.

Results

2,520 (4.4%) individuals moved into retirement communities between 2000 and 2002. There were no substantial differences in the mean change in SRH between those who moved and those who did not. In adjusted and unadjusted models, moving was not significantly associated with changes in SRH. In an analysis stratified by SRH, only those with the best SRH had a significant decline in SRH during the move.

Discussion

SRH mainly remained stable for most people regardless of moving into a retirement community. These findings argue against environmental context being a main determinant of self-perceived health status among older adults.

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

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.

Self-rated health and chronic conditions are associated with blood concentrations of persistent organic pollutants in the general population of Catalonia, Spain

BACKGROUND

Self-rated health (SRH) is a powerful predictor of mortality, morbidity, and need for health services. SRH generally increases with educational level, and decreases with age, number of chronic conditions, and body mass index (BMI). Because human concentrations of most persistent organic pollutants (POPs) also vary by age, education, and BMI, and because of the physiological and clinical effects of POPs, we hypothesized that body concentrations of POPs are inversely associated with SRH.

OBJECTIVES

To analyze the relation between serum concentrations of POPs and SRH in the general population of Catalonia, Spain, taking into account sociodemographic factors and BMI, as well as chronic health conditions and mental disorders, measured by the General Health Questionnaire-12 (GHQ-12).

METHODS

POP serum concentrations were measured by gas chromatography with electron-capture detection in 919 participants of the Catalan Health Interview Survey.

RESULTS

Individuals with higher concentrations of POPs had significantly poorer SRH; e.g., the median concentration of HCB in subjects with poor SRH was twice as high as in subjects with excellent SRH (366 ng/g vs. 169 ng/g, respectively; p-value<0.001). In crude models and in models adjusted for sex and BMI, the POPs-SRH association was often dose-dependent, and the likelihood of poor or regular SRH was 2 to 4-times higher in subjects with POP concentrations in the top quartile. In models adjusted for age or for chronic conditions virtually all ORs were near unity. No associations were found between POP levels and GHQ-12.

CONCLUSIONS

Individuals with higher concentrations of POPs had significantly poorer SRH, an association likely due to age and chronic conditions, but not to sex, education, social class, BMI, or mental disorders.

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

Objective: To create personalized estimates of future health and ability status for older adults. Method: 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. Results: 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. Conclusion: 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.

Using multiple imputation to deal with missing data and attrition in longitudinal studies with repeated measures of patient-reported outcomes

Objective

Missing data is a ubiquitous problem in studies using patient-reported measures, decreasing sample sizes and causing possible bias. In longitudinal studies, special problems relate to attrition and death during follow-up. We describe a methodological approach for the use of multiple imputation (MI) to meet these challenges.

Methods

In a cohort of patients treated with percutaneous coronary intervention followed with use of repetitive questionnaires and information from national registers over 3 years, only 417 out of 1,726 patients had complete data on all measure points and covariates. We suggest strategies for use of MI and different methods for dealing with death along with sensitivity analysis of deviations from the assumption of missing at random, all with the use of standard statistical software. The Mental Component Summary from Short Form 12-item survey was used as an example.

Conclusion

Ignoring missing data may cause bias of unknown size and direction in longitudinal studies. We have illustrated that MI is a feasible method to try to deal with bias due to missing data in longitudinal studies, including attrition and nonresponse, and should be considered in combination with analysis of sensitivity in longitudinal studies. How to handle dropout due to death is still open for debate.

Prospectively measured 10-year changes in health-related quality of life and comparison with cross-sectional estimates in a population-based cohort of adult women and men

PURPOSE

To prospectively assess changes in health-related quality of life (HRQOL) over 10 years, by age and sex, and to compare measured within-person change to estimates of change based on cross-sectional data.

METHODS

Participants in the Canadian Multicentre Osteoporosis Study completed the 36-item short form (SF-36) in 1995/1997 and 2005/2007. Mean within-person changes for domain and summary components were calculated for men and women separately, stratified by 10-year age groups. Projected changes based on published age- and sex-stratified cross-sectional data were also calculated. Mean differences between the two methods were then estimated, along with the 95 % credible intervals of the differences.

RESULTS

Data were available for 5,569/9,423 (59.1 %) of the original cohort. Prospectively collected 10-year changes suggested that the four physically oriented domains declined in all but the youngest group of men and women, with declines in the elderly men exceeding 25 points. The four mentally oriented domains tended to improve over time, only showing substantial declines in vitality and role emotional in older women, and all four domains in older men. Cross-sectional estimates identified a similar pattern of change but with a smaller magnitude, particularly in men. Correspondence between the two methods was generally high.

CONCLUSIONS

Changes in HRQOL may be minimal over much of the life span, but physically oriented HRQOL can decline substantially after middle age. Although clinically relevant declines were more evident in prospectively collected data, differences in 10-year age increments of cross-sectional data may be a reasonable proxy for longitudinal changes, at least in those under 65 years of age. Results provide additional insight into the natural progression of HRQOL in the general population.

Pharmacologic regimens for knee osteoarthritis prevention: can they be cost-effective?

OBJECTIVE

We sought to determine the target populations and drug efficacy, toxicity, cost, and initiation age thresholds under which a pharmacologic regimen for knee osteoarthritis (OA) prevention could be cost-effective.

DESIGN

We used the Osteoarthritis Policy (OAPol) Model, a validated state-transition simulation model of knee OA, to evaluate the cost-effectiveness of using disease-modifying OA drugs (DMOADs) as prophylaxis for the disease. We assessed four cohorts at varying risk for developing OA: (1) no risk factors, (2) obese, (3) history of knee injury, and (4) high-risk (obese with history of knee injury). The base case DMOAD was initiated at age 50 with 40% efficacy in the first year, 5% failure per subsequent year, 0.22% major toxicity, and annual cost of $1,000. Outcomes included costs, quality-adjusted life expectancy (QALE), and incremental cost-effectiveness ratios (ICERs). Key parameters were varied in sensitivity analyses.

RESULTS

For the high-risk cohort, base case prophylaxis increased quality-adjusted life-years (QALYs) by 0.04 and lifetime costs by $4,600, and produced an ICER of $118,000 per QALY gained. ICERs >$150,000/QALY were observed when comparing the base case DMOAD to the standard of care in the knee injury only cohort; for the obese only and no risk factors cohorts, the base case DMOAD was less cost-effective than the standard of care. Regimens priced at $3,000 per year and higher demonstrated ICERs above cost-effectiveness thresholds consistent with current US standards.

CONCLUSIONS

The cost-effectiveness of DMOADs for OA prevention for persons at high risk for incident OA may be comparable to other accepted preventive therapies.

Multilevel socioeconomic status and incidence of frailty post myocardial infarction

BACKGROUND

Frailty predicts mortality and hospitalizations in post-myocardial infarction (MI) patients. Socioeconomic status (SES) demonstrates a clear relationship with post-MI outcomes and is also associated with community frailty; however this relationship has yet to be evaluated in post-MI patients. We investigated the predictive value of socioeconomic factors in the development of post-MI frailty.

METHODS

A cohort of 1151 post-MI patients was followed up from initial hospitalization in 1992-1993 for 10-13 years. Individual and neighborhood SES measures were assessed at baseline and frailty was assessed during follow-up via an index of deficit accumulation. Logistic regression models and discrimination indices enabled determination of the predictive value of socioeconomic factors over basic clinical variables in classifying frailty risk.

RESULTS

During follow-up, 399 patients (35%) developed frailty. Individual and neighborhood SES were significantly and independently associated with the risk of developing frailty. Low income patients had more than twice the risk of becoming frail compared with those with high income [odds ratio (OR), 2.29, 95% CI 1.41-3.73]; while being in the lower vs. upper neighborhood SES tertile was associated with a 60% increased odds (OR, 1.60, 95% CI 1.03-2.49). Inclusion of multilevel SES yielded substantial gains in c-statistic (0.70 to 0.76), net reclassification improvement (21.4%) and integrated discrimination improvement (6.4%) over basic clinical factors (all p<0.001), indicating increased predictive value and gains in sensitivity and specificity.

CONCLUSIONS

Individual and neighborhood socioeconomic factors influence the development of frailty post-MI, and contribute to risk discrimination in this population.

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

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.

Disease-modifying drugs for knee osteoarthritis: can they be cost-effective?

OBJECTIVE

Disease-modifying osteoarthritis drugs (DMOADs) are under development. Our goal was to determine efficacy, toxicity, and cost thresholds under which DMOADs would be a cost-effective knee OA treatment.

DESIGN

We used the Osteoarthritis Policy Model, a validated computer simulation of knee OA, to compare guideline-concordant care to strategies that insert DMOADs into the care sequence. The guideline-concordant care sequence included conservative pain management, corticosteroid injections, total knee replacement (TKR), and revision TKR. Base case DMOAD characteristics included: 50% chance of suspending progression in the first year (resumption rate of 10% thereafter) and 30% pain relief among those with suspended progression; 0.5%/year risk of major toxicity; and costs of $1,000/year. In sensitivity analyses, we varied suspended progression (20-100%), pain relief (10-100%), major toxicity (0.1-2%), and cost ($1,000-$7,000). Outcomes included costs, quality-adjusted life expectancy, incremental cost-effectiveness ratios (ICERs), and TKR utilization.

RESULTS

Base case DMOADs added 4.00 quality-adjusted life years (QALYs) and $230,000 per 100 persons, with an ICER of $57,500/QALY. DMOADs reduced need for TKR by 15%. Cost-effectiveness was most sensitive to likelihoods of suspended progression and pain relief. DMOADs costing $3,000/year achieved ICERs below $100,000/QALY if the likelihoods of suspended progression and pain relief were 20% and 70%. At a cost of $5,000, these ICERs were attained if the likelihoods of suspended progression and pain relief were both 60%.

CONCLUSIONS

Cost, suspended progression, and pain relief are key drivers of value for DMOADs. Plausible combinations of these factors could reduce need for TKR and satisfy commonly cited cost-effectiveness criteria.

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

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.

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

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.

Association of claims-based quality of care measures with outcomes among community-dwelling vulnerable elders

BACKGROUND

Few studies examine the link between measured process of care and outcome.

OBJECTIVE

To evaluate the relationship of claims-based assessment of process of care to subsequent function and survival.

RESEARCH DESIGN

Retrospective cohort study using claims from 1999 to assess performance on 41 quality indicators (QIs) from the Assessing Care of Vulnerable Elders (ACOVE) measurement set on functional decline and death in 2000.

SETTING

Community-dwelling individuals.

SUBJECTS

All persons ≥75 years enrolled in Medicare and Medicaid in 19 California counties in 1998 and 1999 who received In Home Supportive Services.

MEASURES

Quality of care index, activities of daily living, and instrumental activities of daily living (IADL) need indices, mortality.

RESULTS

Total 21,310 persons were eligible for a mean of 7.1 QIs; and received 46% of recommended care. The ADL index increased from 8.1 to 11.6 between baseline and follow-up. The IADL index increased from 13.6 to 14.1. Fifteen percent of the cohort died in 2000. After accounting for number of QIs triggered, baseline function and other covariates, better quality was associated with better function at follow-up. Ten percent better quality was associated at follow-up with 0.21 lower ADL need score [95% confidence interval (CI), 0.25-0.17], 0.022 lower IADL need score (95% CI, 0.032-0.013), and lower odds of death (0.91; 95% CI, 0.89 to 0.93).

CONCLUSIONS

Routinely collected data implementing ACOVE measures for community vulnerable elders generate quality scores that are directly related to patient functional and survival outcomes. These findings suggest that population-based assessment of care is feasible for vulnerable older persons.

Impact of obesity and knee osteoarthritis on morbidity and mortality in older Americans

BACKGROUND

Obesity and knee osteoarthritis are among the most frequent chronic conditions affecting Americans aged 50 to 84 years.

OBJECTIVE

To estimate quality-adjusted life-years lost due to obesity and knee osteoarthritis and health benefits of reducing obesity prevalence to levels observed a decade ago.

DESIGN

The U.S. Census and obesity data from national data sources were combined with estimated prevalence of symptomatic knee osteoarthritis to assign persons aged 50 to 84 years to 4 subpopulations: nonobese without knee osteoarthritis (reference group), nonobese with knee osteoarthritis, obese without knee osteoarthritis, and obese with knee osteoarthritis. The Osteoarthritis Policy Model, a computer simulation model of knee osteoarthritis and obesity, was used to estimate quality-adjusted life-year losses due to knee osteoarthritis and obesity in comparison with the reference group.

SETTING

United States.

PARTICIPANTS

U.S. population aged 50 to 84 years.

MEASUREMENTS

Quality-adjusted life-years lost owing to knee osteoarthritis and obesity.

RESULTS

Estimated total losses of per-person quality-adjusted life-years ranged from 1.857 in nonobese persons with knee osteoarthritis to 3.501 for persons affected by both conditions, resulting in a total of 86.0 million quality-adjusted life-years lost due to obesity, knee osteoarthritis, or both. Quality-adjusted life-years lost due to knee osteoarthritis and/or obesity represent 10% to 25% of the remaining quality-adjusted survival of persons aged 50 to 84 years. Hispanic and black women had disproportionately high losses. Model findings suggested that reversing obesity prevalence to levels seen 10 years ago would avert 178,071 cases of coronary heart disease, 889,872 cases of diabetes, and 111,206 total knee replacements. Such a reduction in obesity would increase the quantity of life by 6,318,030 years and improve life expectancy by 7,812,120 quality-adjusted years in U.S. adults aged 50 to 84 years.

LIMITATIONS

Comorbidity incidences were derived from prevalence estimates on the basis of life expectancy of the general population, potentially resulting in conservative underestimates. Calibration analyses were conducted to ensure comparability of model-based projections and data from external sources.

CONCLUSION

The number of quality-adjusted life-years lost owing to knee osteoarthritis and obesity seems to be substantial, with black and Hispanic women experiencing disproportionate losses. Reducing mean body mass index to the levels observed a decade ago in this population would yield substantial health benefits.

PRIMARY FUNDING SOURCE

The National Institutes of Health and the Arthritis Foundation.

Increasing hospice services for elderly patients maintained with hemodialysis

Few dying patients undergoing dialysis receive hospice care. An intervention to facilitate hospice referral was evaluated in a longitudinal prospective cohort study. Five hemodialysis units in Massachusetts were divided into intervention sites (N = 3 clinics) and control sites (N = 2 clinics). Five hundred twelve patients were screened to identify those with indicators of poor prognoses; 133 met the eligibility criteria and consented to participate. Eighty-two intervention subjects and 51 control subjects were followed for a median of 17 months. During that time, 45 died and 16 received hospice services. Directors from the community hospices were approached by the researchers and agreed to provide an educational outreach to the intervention clinics. Renal supportive care teams (RSCTs) consisting mainly of volunteer health-care providers recruited from the dialysis clinics and local hospices were notified about the high-mortality patients. Staff met periodically to discuss their contacts with subjects and/or family members from the intervention clinics, The subjects were encouraged to participate in advance care planning, and they were provided information about hospice resources. The control clinics did not have RSCTs, and their subjects received standard treatment. At the conclusion of the study, hospice services had increased at the intervention sites (p = 0.09), and the subgroup of > or = 65-year-old subjects had undergone a significant increase (p = 0.05) in obtaining hospice care. Greater familiarity between hospice and dialysis staff along with outreach to patients with poor prognoses holds the promise of expanding hospice use--especially for the elderly.

The impact of attrition on the representativeness of cohort studies of older people

Background

There are well-established risk factors, such as lower education, for attrition of study participants. Consequently, the representativeness of the cohort in a longitudinal study may deteriorate over time. Death is a common form of attrition in cohort studies of older people. The aim of this paper is to examine the effects of death and other forms of attrition on risk factor prevalence in the study cohort and the target population over time.

Methods

Differential associations between a risk factor and death and non-death attrition are considered under various hypothetical conditions. Empirical data from the Australian Longitudinal Study on Women's Health (ALSWH) for participants born in 1921-26 are used to identify associations which occur in practice, and national cross-sectional data from Australian Censuses and National Health Surveys are used to illustrate the evolution of bias over approximately ten years.

Results

The hypothetical situations illustrate how death and other attrition can theoretically affect changes in bias over time. Between 1996 and 2008, 28.4% of ALSWH participants died, 16.5% withdrew and 10.4% were lost to follow up. There were differential associations with various risk factors, for example, non-English speaking country of birth was associated with non-death attrition but not death whereas being underweight (body mass index < 18.5) was associated with death but not other forms of attrition. Compared to national data, underrepresentation of women with non-English speaking country of birth increased from 3.9% to 7.2% and over-representation of current and ex-smoking increased from 2.6% to 5.8%.

Conclusions

Deaths occur in both the target population and study cohort, while other forms of attrition occur only in the study cohort. Therefore non-death attrition may cause greater bias than death in longitudinal studies. However although more than a quarter of the oldest participants in the ALSWH died in the 12 years following recruitment, differences from the national population changed only slightly.

Speed of processing training protects self-rated health in older adults: enduring effects observed in the multi-site ACTIVE randomized controlled trial

BACKGROUND

We evaluated the effects of cognitive training on self-rated health at 1, 2, 3, and 5 years post-baseline.

METHODS

In the ACTIVE (Advanced Cognitive Training for Independent and Vital Elderly) randomized controlled trial, 2,802 older adults (>or=65 years) were randomly assigned to memory, reasoning, speed of processing, or no-contact control intervention groups. Complete data were available for 1,804 (64%) of the 2,802 participants at five years. A propensity score model was adjusted for attrition bias. The self-rated health question was coded using the Diehr et al. (2001) transformation (E = 95/VG = 90/G = 80/F = 30/P = 15), and analyzed with change-score regression models.

RESULTS

The speed of processing (vs. no-contact control) group had statistically significant improvements (or protective effects) on changes in self-rated health at the 2, 3 and 5 year follow-ups. The 5-year improvement was 2.8 points (p = 0.03). No significant differences were observed in the memory or reasoning groups at any time.

CONCLUSION

The speed of processing intervention significantly protected self-rated health in ACTIVE, with the average benefit equivalent to half the difference between excellent vs. very good health.

Association of Health Plans' Healthcare Effectiveness Data and Information Set (HEDIS) performance with outcomes of enrollees with diabetes

BACKGROUND

Few quality of care evaluations examine the relationship between clinical processes and patient outcomes.

OBJECTIVE

To determine the association between health plan performance on Healthcare Effectiveness Data and Information Set (HEDIS) clinical processes and intermediate outcome measures and Health Outcomes Survey (HOS) self-reported physical and mental health scores among Medicare plan enrollees with diabetes.

RESEARCH DESIGN

Secondary data analysis of 2002 HEDIS and 2001-2003 HOS data.

SUBJECTS

This study focused on Medicare plan enrollees with self-reported diabetes (N = 8184).

MEASURES

Plan-level HEDIS diabetes care measures for 2002 and longitudinal, patient-level 2001-2003 HOS physical and mental health outcomes scores. Hierarchical linear models estimated the relationship between plan HEDIS performance on diabetes process of care and intermediate outcome measures and 2-year changes in enrollee HOS physical and mental health scores.

RESULTS

Each 10% point improvement in plan performance on HEDIS intermediate outcomes (ie, the proportion of well-controlled diabetes) was related to significant positive increase in the probability of being healthy as measured by both enrollee physical health scores (7 percentage point increase, P < 0.05) and mental health scores (11 percentage point increase, P < 0.01). Similar increases in plan process of care measures were associated with increases in the probability of being healthy as measured by enrollee mental health scores (11 percentage point increase, P < 0.001).

CONCLUSIONS

This study represents one of the first attempts to link plan HEDIS performance to changes in enrollee health. The results suggest that improved quality of care, as measured by process and intermediate outcomes measures for diabetes, can result in better health among patients with diabetes. Further research should address whether this relationship exists in other quality measures, clinical conditions, and populations.

A modified Wilcoxon test for non-negative distributions with a clump of zeros

Comparing two samples with a continuous non-negative score, e.g. a utility score over [0, 1], with a substantial proportion, say 50 per cent, scoring 0 presents distributional problems for most standard tests. A Wilcoxon rank test can be used, but the large number of ties reduces power. I propose a new test, the Wilcoxon rank-sum test performed after removing an equal (and maximal) number of 0's from each sample. This test recovers much of the power. Compared with a (directional) modification of a two-part test proposed by Lachenbruch, the truncated Wilcoxon has similar power when the non-zero scores are independent of the proportion of zeros, but, unlike the two-part test, the truncated Wilcoxon is relatively unaffected when these processes are dependent.

The aftermath of hip fracture: discharge placement, functional status change, and mortality

The authors prospectively explored the consequences of hip fracture with regard to discharge placement, functional status, and mortality using the Survey on Assets and Health Dynamics Among the Oldest Old (AHEAD). Data from baseline (1993) AHEAD interviews and biennial follow-up interviews were linked to Medicare claims data from 1993-2005. There were 495 postbaseline hip fractures among 5,511 respondents aged >or=69 years. Mean age at hip fracture was 85 years; 73% of fracture patients were white women, 45% had pertrochanteric fractures, and 55% underwent surgical pinning. Most patients (58%) were discharged to a nursing facility, with 14% being discharged to their homes. In-hospital, 6-month, and 1-year mortality were 2.7%, 19%, and 26%, respectively. Declines in functional-status-scale scores ranged from 29% on the fine motor skills scale to 56% on the mobility index. Mean scale score declines were 1.9 for activities of daily living, 1.7 for instrumental activities of daily living, and 2.2 for depressive symptoms; scores on mobility, large muscle, gross motor, and cognitive status scales worsened by 2.3, 1.6, 2.2, and 2.5 points, respectively. Hip fracture characteristics, socioeconomic status, and year of fracture were significantly associated with discharge placement. Sex, age, dementia, and frailty were significantly associated with mortality. This is one of the few studies to prospectively capture these declines in functional status after hip fracture.

Determinants of self-reported health status in a population-based sample of persons with radiographic knee osteoarthritis

OBJECTIVE

Knee osteoarthritis (OA) is highly prevalent and disabling. Patients with radiographic knee OA may experience pain and functional impairment, which can diminish their health status. Our objective was to determine factors associated with self-reported health status in a national population-based sample with radiographic knee OA.

METHODS

Our sample included all of the Third National Health and Nutrition Examination Survey (NHANES-III) participants who underwent a knee radiograph and were found to have radiographic OA (defined as Kellgren/Lawrence grade 2 or higher). Self-reported health status was determined by asking the participant to rate their overall health as excellent, very good, good, fair, or poor. Self-reported health status was analyzed as an ordinal variable using cumulative logit regression, as a dichotomous variable (excellent/very good/good versus fair/poor) using logistic regression, and as a continuous variable after transformation using linear regression.

RESULTS

A total of 1,021 (42%) of NHANES-III participants with a knee radiograph were included in this analysis. The multivariable analyses were performed on 1,009 (99%) of the eligible participants with complete data. We found that nonwhite race, lower income, more comorbidities, and greater functional limitation were associated with worse self-reported health status in all 3 multivariable analyses.

CONCLUSION

This study has quantified the role of clinical, radiographic, and socioeconomic factors associated with self-reported health status in a population-based sample of patients with knee OA. Self-reported health status in patients with knee OA was associated with functional status and comorbidity.

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

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.

Health care expenditure prediction with a single item, self-rated health measure

BACKGROUND

Prediction models that identify populations at risk for high health expenditures can guide the management and allocation of financial resources.

OBJECTIVE

To compare the ability for identifying individuals at risk for high health expenditures between the single-item assessment of general self-rated health (GSRH), "In general, would you say your health is Excellent, Very Good, Good, Fair, or Poor?," and 3 more complex measures.

STUDY DESIGN

We used data from a prospective cohort, representative of the US civilian noninstitutionalized population, to compare the predictive ability of GSRH to: (1) the Short Form-12, (2) the Seattle Index of Comorbidity, and (3) the Diagnostic Cost-Related Groups/Hierarchal Condition Categories Relative-Risk Score. The outcomes were total, pharmacy, and office-based annualized expenditures in the top quintile, decile, and fifth percentile and any inpatient expenditures.

DATA SOURCE

Medical Expenditure Panel Survey panels 8 (2003-2004, n = 7948) and 9 (2004-2005, n = 7921).

RESULTS

The GSRH model predicted the top quintile of expenditures, as well as the SF-12, Seattle Index of Comorbidity, though not as well as the Diagnostic Cost-Related Groups/Hierarchal Condition Categories Relative-Risk Score: total expenditures [area under the curve (AUC): 0.79, 0.80, 0.74, and 0.84, respectively], pharmacy expenditures (AUC: 0.83, 0.83, 0.76, and 0.87, respectively), and office-based expenditures (AUC: 0.73, 0.74, 0.68, and 0.78, respectively), as well as any hospital inpatient expenditures (AUC: 0.74, 0.76, 0.72, and 0.78, respectively). Results were similar for the decile and fifth percentile expenditure cut-points.

CONCLUSIONS

A simple model of GSRH and age robustly stratifies populations and predicts future health expenditures generally as well as more complex models.

A novel interdisciplinary analgesic program reduces pain and improves function in older adults after orthopedic surgery

OBJECTIVES

To examine the effect of a multicomponent intervention on pain and function after orthopedic surgery.

DESIGN

Controlled prospective propensity score-matched clinical trial.

SETTING

New York City acute rehabilitation hospital.

PARTICIPANTS

Two hundred forty-nine patients admitted to rehabilitation after hip fracture repair (n=51) or hip (n=64) or knee (n=134) arthroplasty.

INTERVENTION

Pain assessment at rest and with physical therapy (PT) by staff using numeric rating scales (1 to 5). Physician protocols for standing analgesia and preemptive analgesia before PT were implemented on the intervention unit. Control unit patients received usual care.

MEASUREMENTS

Pain, analgesic prescribing, gait speed, transfer time, and percentage of PT sessions completed during admission. Pain and difficulty walking at 6, 12, 18, and 24 weeks after discharge.

RESULTS

In multivariable analyses intervention patients were significantly more likely than controls to report no or mild pain at rest (66% vs 49%, P=.004) and with PT (52% vs 38%, P=.02) on average for the first 7 days of rehabilitation, had faster 8-foot-walk times on Days 4 (9.3 seconds vs 13.2 seconds, P=.02) and 7 (6.9 vs 9.2 seconds, P=.02), received more analgesia (23.6 vs 15.6 mg of morphine sulfate equivalents per day, P<.001), were more likely to receive standing orders for analgesia (98% vs 48%, P<.001), and had significantly shorter lengths of stay (10.1 vs 11.3 days, P=.005). At 6 months, intervention patients were less likely than controls to report moderate to severe pain with walking (4% vs 15%, P=.02) and that pain did not interfere with walking (7% vs 18%, P=.004) and were less likely to be taking analgesics (35% vs 51%, P=.03).

CONCLUSION

The intervention improved postoperative pain, reduced chronic pain, and improved function.

Quality of life before intensive care unit admission is a predictor of survival

INTRODUCTION

Predicting whether a critically ill patient will survive intensive care treatment remains difficult. The advantages of a validated strategy to identify those patients who will not benefit from intensive care unit (ICU) treatment are evident. Providing critical care treatment to patients who will ultimately die in the ICU is accompanied by an enormous emotional and physical burden for both patients and their relatives. The purpose of the present study was to examine whether health-related quality of life (HRQOL) before admission to the ICU can be used as a predictor of mortality.

METHODS

We conducted a prospective cohort study in a university-affiliated teaching hospital. Patients admitted to the ICU for longer than 48 hours were included. Close relatives completed the Short-form 36 (SF-36) within the first 48 hours of admission to assess pre-admission HRQOL of the patient. Mortality was evaluated from ICU admittance until 6 months after ICU discharge. Logistic regression and receiver operating characteristic analyses were used to assess the predictive value for mortality using five models: the first question of the SF-36 on general health (model A); HRQOL measured using the physical component score (PCS) and mental component score (MCS) of the SF-36 (model B); the Acute Physiology and Chronic Health Evaluation (APACHE) II score (an accepted mortality prediction model in ICU patients; model C); general health and APACHE II score (model D); and PCS, MCS and APACHE II score (model E). Classification tables were used to assess the sensitivity, specificity, positive and negative predictive values, and likelihood ratios.

RESULTS

A total of 451 patients were included within 48 hours of admission to the ICU. At 6 months of follow up, 159 patients had died and 40 patients were lost to follow up. When the general health item was used as an estimate of HRQOL, area under the curve for model A (0.719) was comparable to that of model C (0.721) and slightly better than that of model D (0.760). When PCS and MCS were used, the area under the curve for model B (0.736) was comparable to that of model C (0.721) and slightly better than that of model E (0.768). When using the general health item, the sensitivity and specificity in model D (sensitivity 0.52 and specificity 0.81) were similar to those in model A (0.45 and 0.80). Similar results were found when using the MCS and PCS.

CONCLUSION

This study shows that the pre-admission HRQOL measured with either the one-item general health question or the complete SF-36 is as good at predicting survival/mortality in ICU patients as the APACHE II score. The value of these measures in clinical practice is limited, although it seems sensible to incorporate assessment of HRQOL into the many variables considered when deciding whether a patient should be admitted to the ICU.

Self-rated health: changes, trajectories, and their antecedents among African Americans

OBJECTIVE

Little is known about changes in self-rated health (SRH) among African Americans.

METHOD

We examined SRH changes and trajectories among 998 African Americans 49 to 65 years old who we reinterviewed annually for 4 years, using multinomial logistic regression and mixed effect models.

RESULTS

Fifty-five percent had the same SRH at baseline and 4 years later, 25% improved, and 20% declined. Over time, men were more likely to report lower SRH levels, individuals with hypertension were less likely to report lower SRH levels, and those with congestive heart failure at baseline were more likely to report higher SRH levels. Lower SRH trajectory intercepts were observed for those with lower socioeconomic status, poorer health habits, disease history, and worse functional status. Those with better cognitive status had higher SRH trajectory intercepts.

DISCUSSION

The decline in SRH levels among 49- to 65-year-old African Americans is comparable to that of Whites.

Analysis and interpretation of results based on patient-reported outcomes

This article is part of a series of manuscripts dealing with the incorporation of patient-reported outcomes (PROs) into clinical trials. The issues dealt with in this manuscript concern the common pitfalls to avoid in statistical analysis and interpretation of PROs. Specifically, the questions addressed by this manuscript involve the analysis pitfalls with PRO data in clinical trials and how can they be avoided (e.g.,missing data, multiplicity, null results etc.). The manuscript provides key literature for existing resources and proposes new guidelines.

Quality of life at the end of life

Background

Little is known about self-perceived quality of life (QOL) near the end of life, because such information is difficult to collect and to interpret. Here, we describe QOL in the weeks near death and determine correlates of QOL over time, with emphasis on accounting for death and missing data.

Methods

Data on QOL were collected approximately every week in an ongoing randomized trial involving persons at the end of life. We used these data to describe QOL in the 52 weeks after enrollment in the trial (prospective analysis, N = 115), and also in the 10 weeks just prior to death (retrospective analysis, N = 83). The analysis consisted of graphs and regressions that accounted explicitly for death and imputed missing data.

Results

QOL was better than expected until the final 3 weeks of life, when a terminal drop was observed. Gender, race, education, cancer, and baseline health status were not significantly related to the number of “weeks of good-quality life” (WQL) during the study period. Persons younger than 60 had significantly higher WQL than older persons in the prospective analysis, but significantly lower WQL in the retrospective analysis. The retrospective results were somewhat sensitive to the imputation model.

Conclusion

In this exploratory study, QOL was better than expected in persons at the end of life, but special interventions may be needed for persons approaching a premature death, and also for the last 3 weeks of life. Our descriptions of the trajectory of QOL at the end of life may help other investigators to plan and analyze future studies of QOL. Methodology for dealing with death and the high amount of missing data in longitudinal studies at the end of life needs further investigation.

Change in health status and mortality as indicators of outcomes: comparison between the Medicare Advantage Program and the Veterans Health Administration

BACKGROUND

Comparing health outcomes with adequate methodology is central to performance assessments of health care systems. We compared the Medicare Advantage Program (MAP) and the Veterans Health Administration (VHA) with regard to changes in health status and mortality.

METHODS

We used the Death-Master-File for vital status and the Short-Form 36 to determine physical (PCS) and mental (MCS) health at baseline and at 2 years. We compared the probability of being alive with the same or better (than would be expected by chance) PCS (or MCS) at 2 years and mortality, while adjusting for case-mix. Given the geographic variations in MAP enrollment, we did a regional sub-analysis.

RESULTS

There were no significant differences in the probability of being alive with the same or better PCS except for the South (VHA 65.8% vs. MAP 62.5%, P = .0014). VHA patients had a slightly higher probability than MAP patients of being alive with the same or better MCS (71.8% vs. 70.1%, P = .002) but no significant regional variations. The hazard ratios for mortality in the MAP were higher than in the VHA across all regions.

CONCLUSION

With the use of appropriate methodology, we found small differences in 2-year health outcomes that favor the VHA.