Residential Street Block Disorder and Biological Markers of Aging in Older Adults: The National Health and Aging Trends Study

Background: Residential environments are associated with older adults' health, but underlying physiologic causal mechanisms are not well understood. As adults age, street blocks are likely more relevant to their health than the larger neighborhood environment. This study examined the effects of adverse street block conditions on aging biomarkers among older adults. Methods: We included community-dwelling Medicare benefciaries aged 67 and older with 2017 biomarker data from the nationally representative National Health and Aging Trends Study (n = 4357). Street block disorder in 2016 was measured using interviewer report of any trash/glass/litter, graffti, or vacant buildings on participants' blocks. Propensity score models were used to create balanced groups with regard to multiple 2015 participant characteristics, including demographic, socioeconomic, residence, and early-life characteristics. Linear regressions modeled street block disorder as a predictor of 4 aging biomarkers, hemoglobin A1C, high-sensitivity C-reactive protein, interleukin-6, and cytomegalovirus antibodies, before and after applying propensity score weighting. Results: Adjusting for participant sociodemographic characteristics and applying propensity score weights, living on a block with any disorder was associated with 2% higher mean hemoglobin A1C levels (95% confdence interval [CI]: 0.002-0.03), 13% higher C-reactive protein (95% CI: 0.03-0.23), 10% higher interleukin-6 (95% CI: 0.02-0.19), and 19% more cytomegalovirus antibodies (95% CI: 0.09-0.29) compared to living on a block with no disorder. Conclusions: Street block disorder predicted subsequent aging biomarkers after applying a propensity score approach to account for confounding among a national sample of older adults. Targeting street-level residential contexts for intervention may reduce the risk for poor health in older adults.