RESUMEN
OBJECTIVE: Residing in communities characterized by socioeconomic disadvantage confers risk of cardiometabolic diseases. Residing in disadvantaged communities may also confer the risk of neurodegenerative brain changes via cardiometabolic pathways. This study tested whether features of communities-apart from conventional socioeconomic characteristics-relate not only to cardiometabolic risk but also to relative tissue reductions in the cerebral cortex and hippocampus. METHODS: Participants were 699 adults aged 30 to 54 years (340 women; 22.5% non-White) whose addresses were geocoded to compute community indicators of socioeconomic disadvantage, as well as air and toxic chemical pollutant exposures, homicide rates, concentration of employment opportunities, land use (green space), and availability of supermarkets and local resources. Participants also underwent assessments of cortical and hippocampal volumes and cardiometabolic risk factors (adiposity, blood pressure, fasting glucose, and lipids). RESULTS: Multilevel structural equation modeling demonstrated that cardiometabolic risk was associated with community disadvantage ( ß = 0.10, 95% confidence interval [CI] = 0.01 to 0.18), as well as chemical pollution ( ß = 0.11, 95% CI = 0.02 to 0.19), homicide rates ( ß = 0.10, 95% CI = 0.01 to 0.18), employment opportunities ( ß = -0.16, 95% CI = -0.27 to -0.04), and green space ( ß = -0.12, 95% CI = -0.20 to -0.04). Moreover, cardiometabolic risk indirectly mediated the associations of several of these community features and brain tissue volumes. Some associations were nonlinear, and none were explained by participants' individual-level socioeconomic characteristics. CONCLUSIONS: Features of communities other than conventional indicators of socioeconomic disadvantage may represent nonredundant correlates of cardiometabolic risk and brain tissue morphology in midlife.