Sociodemographic shifts influencing Black-White disparity in ADL and IADL disabilities

Late-life disabilities such as ADL and IADL limitations can lead to elevated mortality and health risks for individuals and an increased burden of health care costs for society. Substantial epidemiological evidence has consistently shown that U.S. non-Hispanic black older adults experience a greater prevalence of disability compared to their non-Hispanic white counterparts. Using the Integrated Health Interview Survey (IHIS) and age-period-cohort models, our results showed that black-white disparity in ADL and IADL disabilities increase with age (70-84) for both men and women. The ADL and IADL disparity trends remain stable across each period/survey year (1982-2009) for both genders. While the ADL disparity trends are flat across multiple 5-year cohort bands (1885-1940) for men and women, there appears to be a continuous increase in IADL disparity between the 1915 and 1940 cohorts for women and a less consistent increase between the 1920 and 1940 cohorts for men. We also examined the compositional shifts of the cohort-based ADL and IADL disparity trends with regard to a host of sociodemographic variables. Racial differences in education and income persistently contribute to the ADL/IADL disparities among men and women. While marital status is becoming a more salient contributor to IADL disparity (less clear in ADL disparity) among both genders, region of residence decreases in importance across the cohorts for both genders and types of disabilities. BMI does not seem to play an important role for IADL disparity; however, BMI becomes an increasingly more important contributor to ADL disparity among both genders after the 1920 cohort.