2013. Black-White Disparities in Functional Decline in Older Persons
Sandra Y Moody-Ayers, MD, San Francisco VAMC, K Mehta, San Francisco VAMC, K Lindquist,
San Francisco VAMC, L Sands,
San Francisco VAMC, K Covinsky,
San Francisco VAMC
Objectives: To compare the extent to which different risk domains explain higher rates of poor functional outcomes in black elders.
Methods: We studied 527 black and 3332 white community-dwelling adults aged 70-79 from AHEAD, a national population-based cohort study begun in 1993. Our outcome was functional decline, defined as either decline in 5 Activities of Daily Living (ADL) or death over 2 years. Potential explanatory variables were grouped into 4 risk domains: socioeconomic status (SES), comorbidity, smoking, and cognitive function. We used logistic regression to examine the separate effect of each risk domain on the black-white difference in functional decline.
Results: Blacks were more likely to smoke, have diabetes, hypertension, lower SES, and worse cognitive function than whites (P<.05 for all). In unadjusted analyses, blacks had higher rates of 2-yr functional decline (20% vs.11%, P<.01, OR=2.02, CI=1.40-2.92). The ORs associated with black ethnicity changed little after adjustment for comorbidity (OR=2.00, 95% CI=1.40-2.85) and smoking (OR=1.98, 95% CI=1.37-2.86) while adjustment for SES (OR=1.41, 95% CI=0.96-2.07) reduced, but did not fully explain the excess risk. However, adjustment for cognitive function reduced the OR to 1.04 (CI=0.71-1.54), and thus fully explained the excess risk of functional decline for blacks.
Conclusions: Differences in cognitive status fully explained black-white functional decline differentials among subjects aged 70-79.
Impact: Given the diversity of the veteran population, understanding the reasons underlying health disparities could improve the health care of a substantial number of veterans. Further work at understanding the factors leading to poorer cognitive function in black elders may help reduce their higher rates of poor health outcomes.