Effect of street connectivity on incidence of lower-body functional limitations among middle-aged African Americans

Purpose: We hypothesize that lower street connectivity increases the risk of incident lower-body functional limitations (LBFLs) among urban African Americans aged 49-65 years. Methods: This population-based cohort was interviewed in home visits. Five items measuring LBFL were obtained at baseline and after 3 years. Participants were considered to have LBFL if they reported difficulty on at least two of the five tasks. Census-tract street connectivity was measured as the ratio of the number of street intersections to the maximum possible number of intersections. Results: Of 563 subjects with zero or one LBFL at baseline, 109 (19.4%) experienced two or more LBFLs at the 3-year follow-up. Adjusted logistic regression showed that persons who lived in census tracts with the lowest quartile of street connectivity were 3.45 times (95% confidence interval, 1.21-9.78) more likely to develop two or more LBFLs than those who lived in census tracts with the highest quartile of street connectivity independent of other important environmental factors. Conclusions: Areas with low street connectivity appear to be an independent contributor to the risk of incident LBFL in middle-aged African Americans.