Community Socioeconomic Disadvantage Relates to White Matter Hyperintensity Burden in Mid-to-Late Life Adults

Residing in communities characterized by socioeconomic disadvantage may confer risk for neurodegenerative brain changes and future neuropathology. Based on prior evidence, this study tested the hypotheses that (1) community-level disadvantage would relate independently of individual-level socioeconomic position to white matter hyperintensities (WMHs), which reflect subclinical brain pathology that may presage later dementia; and (2) this association would be partly explained by blood pressure, cardiometabolic risk, and/or systemic levels of inflammation. These hypotheses were examined among otherwise healthy middle-aged and older adults without clinical dementia at testing.

Participants were 388 adults aged 40 to 72 years (53% female; 12% non-White) whose street addresses were entered into the Neighborhood Atlas to compute Area Deprivation Index scores by census block. Participants also underwent high-resolution (7 T) brain imaging to assess total WMH volume normalized for intracranial volume, and assessment of blood pressure, cardiometabolic (adiposity, lipids, glucose and insulin), and inflammatory (interleukin-6 and C-reactive protein) risk factors.

Linear regression models showed that higher community deprivation on the ADI was associated with greater WMH volume, independently of age, sex, years of education, smoking, and time between study visits (beta=0.11, p =.028). This association was largely independent of blood pressure, cardiometabolic risk, and systemic inflammation.

The present novel findings add to growing evidence that community disadvantage relates to preclinical neurodegenerative changes, which may contribute to accelerated brain and cognitive aging. Future work is warranted to better understand pathways that link residential environments to brain health and to identify targets for community and public policy interventions.