Rowland W. Chang

Racial/Ethnic Differences in Rates of Depression Among Preretirement Adults

OBJECTIVES We estimated racial/ethnic differences in rates of major depression and investigated possible mediators. METHODS Depression prevalence rates among African American, Hispanic, and White adults were estimated from a population-based national sample and adjusted for potential confounders. RESULTS African Americans (odds ratio [OR] = 1.16, 95% confidence interval [CI] = 0.93, 1.44) and Hispanics (OR = 1.44, 95% CI = 1.02, 2.04) exhibited elevated rates of major depression relative to Whites. After control for confounders, Hispanics and Whites exhibited similar rates, and African Americans exhibited significantly lower rates than Whites. CONCLUSIONS Major depression and factors associated with depression were more frequent among members of minority groups than among Whites. Elevated depression rates among minority individuals are largely associated with greater health burdens and lack of health insurance, factors amenable to public policy intervention.

Functional Outcome and Patient Satisfaction in Total Knee Patients Over the Age of 75

Seventy-four patients, age 75 or older, who had undergone 98 primary total knee arthroplasties were evaluated in a retrospective cohort study, with validated questionnaires that assessed self-reported pain, physical function, mental health, and satisfaction. Average follow-up period was 34 months (range, 12-67 months). Overall, 90.8% reported improvement, 88.8% were satisfied with the results of surgery, and 91.8% felt they had made the right decision. Dissatisfaction with the results correlated with poorer mental health scores, decreased physical function, and increased bodily pain scores (P < .05). Satisfaction was correlated with better pain scores on the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and SF-36 (P < .05) but not with Hospital for Special Surgery scores (P = .328). Poor surgical results leading to revision surgery (5%) were associated with preoperative deformity greater than 20 degrees. Based on this patient-assessed outcome analysis, total knee arthroplasty is a worthwhile and beneficial procedure in the elderly.

Arthritis prevalence and activity limitations in older adults

OBJECTIVE To evaluate the prevalence of arthritis and activity limitations among older Americans by assessing their demographic, ethnic, and economic characteristics. METHODS Data from the Asset and Health Dynamic Survey Among the Oldest Old (AHEAD), a national probability sample of community-dwelling adults born before 1924, were analyzed cross-sectionally. Arthritis that resulted in a physicians visit or a joint replacement not associated with a hip fracture was ascertained by self-report. RESULTS The prevalence of arthritis in older adults ranged from 25% in non-Hispanic whites to 40% in non-Hispanic blacks to 44% in Hispanics. A higher prevalence of arthritis was associated with less education as well as lower income and less wealth. The prevalence of limitations in activities of daily living (ADL) among non-Hispanic white, non-Hispanic black, and Hispanic adults who reported arthritis only was 29%, 30%, and 37%, respectively, and increased to 48%, 57%, and 56%, respectively, among those reporting arthritis plus other chronic conditions, after adjustment for age and sex. CONCLUSION Non-Hispanic black and Hispanic older adults reported having arthritis at a substantially higher frequency than did non-Hispanic whites. In addition, Hispanics reported higher rates of ADL limitations than did non-Hispanic whites with comparable disease burden. Further study is needed to confirm and elucidate the reasons for these racial and economic disparities in older populations.

Objective physical activity measurement in the osteoarthritis initiative: Are guidelines being met?†

OBJECTIVE Osteoarthritis (OA) clinical practice guidelines identify a substantial therapeutic role for physical activity, but objective information about the physical activity of this population is lacking. The aim of this study was to objectively measure levels of physical activity in adults with knee OA and report the prevalence of meeting public health physical activity guidelines. METHODS Cross-sectional accelerometry data from 1,111 adults with radiographic knee OA (49-84 years old) participating in the Osteoarthritis Initiative accelerometry monitoring ancillary study were assessed for meeting the aerobic component of the 2008 Physical Activity Guidelines for Americans (≥150 minutes/week moderate-to-vigorous-intensity activity lasting ≥10 minutes). Quantile regression was used to test median sex differences in physical activity levels. RESULTS Aerobic physical activity guidelines were met by 12.9% of men and 7.7% of women with knee OA. A substantial proportion of men and women (40.1% and 56.5%, respectively) were inactive, having done no moderate-to-vigorous activity that lasted 10 minutes or more during the 7 days. Although men engaged in significantly more moderate-to-vigorous activity (average daily minutes 20.7 versus 12.3), they also spent more time in no or very-low-intensity activity than women (average daily minutes 608.2 versus 585.8). CONCLUSION Despite substantial health benefits from physical activity, adults with knee OA were particularly inactive based on objective accelerometry monitoring. The proportions of men and women who met public health physical activity guidelines were substantially less than those previously reported based on self-reported activity in arthritis populations. These findings support intensified public health efforts to increase physical activity levels among people with knee OA.

Arthritis and Heart Disease as Risk Factors for Major Depression: The Role of Functional Limitation.

Background:Major depression in later life is highest among people with chronic illness. Identifying amenable factors that mediate the relationship between known risk factors such as arthritis and heart disease with major depression is important to the design of clinical and public health strategies to reduce depression and its consequences. Objective:This study investigates factors amenable to clinical and public health intervention that could mediate the relationship between chronic illness and major depression. Design:Population-based national sample. Setting:United States preretirement age (54–65) adults. Participants:A total of 7825 participants from the 1996 Health and Retirement Survey. Measurement:The outcome is major depression based on standardized assessment. Independent variables include sociodemographics chronic illness profile, functional limitation, health and medical access. Results:A substantial burden of major depression is related to chronic illness, particularly arthritis (attributable risk [AR], 18.1%; 95% confidence interval [CI], 9.9–25.6) and heart disease (AR, 17.6%; 95% CI, 13.4–21.7). Functional limitation is the strongest investigated factor associated with depression (AR, 34.4%; 95% CI, 24.8–42.7) and attenuates the associations of arthritis and heart disease with depression. Conclusion:Functional limitation mediates the association of arthritis and heart disease with major depression. This relationship offers potential clinical and public health strategies to reduce major depression in older adults through intervention and management of functional limitation. Alternatively, it might be possible to reduce functional loss through screening for depression, particularly among people with functional limitation, and effective mental health treatment. The importance for clinical management of depression, comorbidity, and functional limitation spectrum supports the value of systems-based medicine.

The Critical Path Method in Stroke Rehabilitation: Lessons from an Experiment in Cost Containment and Outcome Improvement

This study tested the effects of a project network technique called the Critical Path Method (CPM) on the costs and outcomes of inpatient team stroke rehabilitation. On admission to a large, academic, inpatient rehabilitation hospital adults who had a recent (< 120 days) stroke were randomly assigned to receive rehabilitation services from a team trained in CPM (N = 53) or from usual care teams (N = 68). Results showed no significant difference between groups in length of stay, hospital charges, or functional status at discharge. CPM may be effective in patient care services that are less influenced by specialization, professional issues, and external regulation and in settings where patient outcomes are relatively fixed and predictable, and medical care is integrated across institutions.

Physical activity levels and functional performance in the osteoarthritis initiative: A graded relationship

OBJECTIVE Physical activity improves function in adults with arthritis, but it is unknown if there is a graded relationship between physical activity and functional benefit. This study was undertaken to examine the cross-sectional and longitudinal relationship between self-reported physical activity and observed functional performance in adults with knee osteoarthritis (OA). METHODS The Osteoarthritis Initiative cohort included 2,589 patients with knee OA (2,301 with longitudinal followup data) who were ages 45-79 years at baseline. Prospective annual functional performance was assessed for 2 years using timed 20-meter walk tests. We used linear regression to estimate differences across physical activity quartiles in subsequent function (baseline and 1-year activity predicts 1-year and 2-year function, respectively) adjusted for demographic factors (age, sex, race/ethnicity, education level, and marital status) and health factors (OA severity, knee symptoms, knee pain, knee injury, body mass index, comorbidity, depression, smoking, alcohol use, and other joint pain). RESULTS Increasing physical activity levels had a significant graded relationship to functional performance. Adults in physical activity quartile groups from least active to most active had an average gait speed of 4.0, 4.2, 4.3, and 4.5 feet/second, respectively, at baseline (P for trend<0.001) and 4.0, 4.2, 4.3, and 4.5 feet/second, respectively, after 1 year (P for trend<0.001); increasing trends remained significant after adjusting for covariates. Findings were similar within sex and age groups. CONCLUSION These prospective data indicate a consistent graded relationship between physical activity level and better performance in adults with knee OA. These findings support guidelines that encourage patients with arthritis who cannot attain minimum recommended physical activity to be as active as possible.

Age and racial/ethnic disparities in arthritis-related hip and knee surgeries.

Background:Nearly 18 million Americans experience limitations due to their arthritis. Documented disparities according to racial/ethnic groups in the use of surgical interventions such as knee and hip arthroplasty are largely based on data from Medicare beneficiaries age 65 or older. Whether there are disparities among younger adults has not been previously addressed. Objective:This study assesses age-specific racial/ethnic differences in arthritis-related knee and hip surgeries. Design:Longitudinal (1998–2004) Health and Retirement Study. Setting:National probability sample of US community-dwelling adults. Sample:A total of 2262 black, 1292 Hispanic, and 13,159 white adults age 51 and older. Measurements:The outcome is self-reported 2-year use of arthritis-related hip or knee surgery. Independent variables are demographic (race/ethnicity, age, gender), health needs (arthritis, chronic diseases, obesity, physical activity, and functional limitations), and medical access (income, wealth, education, and health insurance). Longitudinal data methods using discrete survival analysis are used to validly account for repeated (biennial) observations over time. Analyses use person-weights, stratum, and sampling error codes to provide valid inferences to the US population. Results:Black adults under the age of 65 years report similar age/gender adjusted rates of hip/knee arthritis surgeries [hazard ratio (HR) = 1.43, 95% confidence interval (CI) = 0.87–2.38] whereas older blacks (age 65+) have significantly lower rates (HR = 0.38, CI = 0.16–0.55) compared with whites. These relationships hold controlling for health and economic differences. Both under age 65 years (HR = 0.64, CI = 0.12–1.44) and older (age 65+) Hispanic adults (HR = 0.60, CI = 0.32–1.10) report lower utilization rates, although not statistically different than whites. A large portion of the Hispanic disparity is explained by economic differences. Conclusions:These national data document lower rates of arthritis-related hip/knee surgeries for older black versus white adults age 65 or above, consistent with other national studies. However, utilization rates for black versus white under age 65 do not differ. Lower utilization among Hispanics versus whites in both age groups is largely explained by medical access factors. National utilization patterns may vary by age and merit further investigation.

Racial disparities in joint replacement use among older adults.

Background. Although joint replacement can restore function for arthritis patients with severe joint disease, this procedure has not been used equally across racial groups. Differences in joint replacement use are assessed from a national sample. Objective. This study evaluates the role of health conditions and economic access to explain differences in joint replacement among older black and Hispanic minorities relative to white persons. Design. Longitudinal (1993–1995) Asset and Health Dynamics Among the Oldest Old (AHEAD) study. Setting. National probability sample of US community-dwelling older adults. Patient Population. AHEAD participants (n = 6159) aged 69 to 103 years. Measurements. The outcome is subject-reported 2-year use of any arthritis-related joint-replacement. Independent variables are demographics, health needs (arthritis, other medical conditions, functional health), and economic access (income, assets, education, and health insurance). Results. Older minorities reported arthritis-related joint replacements (black: 0.98%; Hispanic: 0.97%, annually) less frequently compared with white persons (1.48% annually). Older minorities were significantly less likely to use joint replacement compared with white persons (OR, 0.37; 95% CI, 0.20, 0.71) controlling for demographics, and arthritis and other health needs. Disparities remained significant (OR, 0.46; 95% CI, 0.22, 0.98) after additionally controlling for economic medical access. Use was lower among people who depended solely on Medicare compared with those with supplemental health insurance (OR, 0.46; 95% CI, 0.22, 0.95). Conclusions. These national data document low rates of arthritis-related joint replacement among older Hispanic persons comparable to black persons. Less use among older minorities compared with white persons is not explained by differences in health needs or economic access. Other cultural and attitudinal factors merit investigation to explain disparities.

Racial/Ethnic Differences in the Development of Disability Among Older Adults

OBJECTIVES We investigated differences in the development of disability in activities of daily living among non-Hispanic Whites, African Americans, Hispanics interviewed in Spanish, and Hispanics interviewed in English. METHODS We estimated 6-year risk for disability development among 8161 participants 65 years or older and free of baseline disability. We evaluated mediating factors amenable to clinical and public health intervention on racial/ethnic difference. RESULTS The risk for developing disability among Hispanics interviewed in English was similar to that among Whites (hazard ratio [HR]=0.99; 95% confidence interval [CI] = 0.6, 1.4) but was substantially higher among African Americans (HR=1.6; 95% CI=1.3, 1.9) and Hispanics interviewed in Spanish (HR=1.8; 95% CI=1.4, 2.1). Adjustment for demographics, health, and socioeconomic status reduced a large portion of those disparities (African American adjusted HR=1.1, Spanish-interviewed Hispanic adjusted HR=1.2). CONCLUSIONS Higher risks for developing disability among older African Americans, and Hispanics interviewed in Spanish compared with Whites were largely attenuated by health and socioeconomic differences. Language- and culture-specific programs to increase physical activity and promote weight maintenance may reduce rates of disability in activities of daily living and reduce racial/ethnic disparities in disability.