Wealth-associated disparities in death and disability in the United States and England

Abstract

IMPORTANCE Low income has been associated with poor health outcomes. Owing to retirement, wealth may be a better marker of financial resources among older adults. OBJECTIVE To determine the association of wealth with mortality and disability among older adults in the United States and England. DESIGN, SETTING, AND PARTICIPANTS The US Health and Retirement Study (HRS) and English Longitudinal Study of Aging (ELSA) are nationally representative cohorts of community-dwelling older adults.We examined 12 173 participants enrolled in HRS and 7599 enrolled in ELSA in 2002. Analyses were stratified by age (54-64 years vs 66-76 years) because many safety-net programs commence around age 65 years. Participants were followed until 2012 for mortality and disability. EXPOSURES Wealth quintile, based on total net worth in 2002. MAIN OUTCOMES AND MEASURES Mortality and disability, defined as difficulty performing an activity of daily living. RESULTS A total of 6233 US respondents and 4325 English respondents aged 54 to 64 years (younger cohort) and 5940 US respondents and 3274 English respondents aged 66 to 76 years (older cohort) were analyzed for the mortality outcome. Slightly over half of respondents were women (HRS: 6570, 54%; ELSA: 3974, 52% ). A higher proportion of respondents from HRS were nonwhite compared with ELSA in both the younger (14% vs 3% ) and the older (13% vs 3% ) age cohorts.We found increased risk of death and disability as wealth decreased. In the United States, participants aged 54 to 64 years in the lowest wealth quintile (Q1) (≤$39 000) had a 17% mortality risk and 48% disability risk over 10 years, whereas in the highest wealth quintile (Q5) (>$560 000) participants had a 5% mortality risk and 15% disability risk (mortality hazard ratio [HR], 3.3; 95% CI, 2.0-5.6; P < .001; disability subhazard ratio [sHR], 4.0; 95% CI, 2.9-5.6; P < .001). In England, participants aged 54 to 64 years in Q1 (≤£34,000) had a 16% mortality risk and 42% disability risk over 10 years, whereas Q5 participants (>£310,550) had a 4% mortality risk and 17% disability risk (mortality HR, 4.4; 95% CI, 2.7-7.0; P < .001; disability sHR, 3.0; 95% CI, 2.1-4.2; P < .001). In 66- to 76-year-old participants, the absolute risks of mortality and disability were higher, but risk gradients across wealth quintiles were similar. When adjusted for sex, age, race, income, and education, HR for mortality and sHR for disability were attenuated but remained statistically significant. CONCLUSIONS AND RELEVANCE Low wealth was associated with death and disability in both the United States and England. This relationship was apparent from age 54 years and continued into later life. Access to health care may not attenuate wealth-associated disparities in older adults.