Ethnic Differences in Quality of Life in Insured Older Adults with Diabetes Mellitus in an Integrated Delivery System

Objectives: To explore racial and ethnic (ethnic hereafter) differences in health-related quality of life (HRQL) in older adults with diabetes mellitus in an integrated delivery system. Design: Observational cross-sectional study. Setting: Kaiser Permanente Northern California. Participants: Ethnic-stratified, random sample of 6,096 adults with diabetes mellitus aged 60 to 75 who completed a HRQL questionnaire. Measurements: Physical and mental HRQL were measured based on the Medical Outcomes Study 8-item Short Form Survey (range 0�100, mean 50). Age- and sex-adjusted weighted linear regression models estimated associations between ethnicity and HRQL and evaluated potential mediators (socioeconomic status, acculturation, health behaviors, diabetes mellitus�related conditions). Differences in ethnic-specific, adjusted mean HRQL scores were tested (reference whites). Results: Physical HRQL was better for Filipinos (48.3, 95% confidence interval (CI) = 47.0�49.6, P < .001), Asians (48.1, 95% CI = 46.8�49.3, P < .001), Hispanics (45.1, 95% CI = 44.2�46.0, P < .001), and blacks (44.2, 95% CI = 43.3�45.1, P = .04) than whites (42.9, 95% CI = 42.6�43.2). Adjusting for potential mediators did not change these relationships. Mental HRQL was better only for Asians (52.7, 95% CI = 51.6�53.7, P = .01) than for whites (51.0, 95% CI = 50.7�51.3), but this difference was small and became nonsignificant after adjustment for socioeconomic status, acculturation, health behaviors, and diabetes mellitus�related conditions. Conclusion: In older adults with diabetes mellitus in a well-established integrated healthcare delivery system, ethnic minorities had better physical HRQL than whites. Equal access to care in an integrated delivery system may hold promise for reducing health disparities in diabetes mellitus-related patient-reported outcomes.