Diabetes predicts long-term disability in an elderly urban cohort: the Northern Manhattan Study

There are limited data on vascular predictors of long-term disability in Hispanics. We hypothesized that (1) functional status declines over time and (2) vascular risk factors predict functional decline.

The Northern Manhattan Study contains a population-based study of 3298 stroke-free individuals aged 40 years or older, followed for median 11 years. The Barthel Index (BI) was assessed annually. Generalized estimating equations and Cox models were adjusted for demographic, medical, and social risk factors. Stroke and myocardial infarction occurring during follow-up were censored in sensitivity analysis. Secondarily, motor and nonmotor domains of the BI were analyzed.

Mean age (standard deviation) of the cohort (n = 3298) was 69.2 (10) years, 37% were male, 52% Hispanic, 22% diabetic, and 74% hypertensive. There was a mean annual decline of 1.02 BI points (P < .0001). Predictors of decline in BI included age, female sex, diabetes, depression, and normocholesterolemia. Results did not change with censoring. We found similar predictors of BI for motor and nonmotor domains.

In this large, population-based, multiethnic study with long-term follow-up, we found a 1% mean decline in function per year that did not change when vascular events were censored. Diabetes predicted functional decline in the absence of clinical vascular events.