Introduction:
Functional impairments influence the performance of activities of daily living and may result in dependence on others for basic self-care needs. Lower individual-level socioeconomic status (SES) is associated with more self-reported disability and lower measured walking speeds which convey a higher risk of cardiovascular and all-cause mortality. The role of neighborhood-level SES on these functional outcomes has not been widely examined.
Hypothesis:
We hypothesized that residing in a socioeconomically disadvantaged neighborhood is inversely associated with physical function, after accounting for individual-level SES.
Methods:
We included 5,388 participants (42% male, 19% black, mean age: 76 years) from the 2011-2013 examination of the ARIC cohort. Neighborhood SES was constructed from census-tract data and an index score was derived based on aggregate z-score estimates from the following 6 dimensions: median household income; median value of owner-occupied units; % adults with a high school degree; % adults with a college degree; % households receiving interest, dividend or rental income; and % adults employed in executive, managerial or professional occupations. Race-specific tertiles were generated to indicate low, middle and high neighborhood SES. The Short Physical Performance Battery (SPPB) was used to derive a summary score (0-12) of physical function based on the individual’s performance on gait speed, chair stands and balance exercises. Negative binomial regression was used to quantify the difference in the log of expected counts in the SPPB score between race-stratified low, middle and high neighborhood SES, adjusting for age, sex, body mass index (BMI), smoking, hypertension, diabetes, study center, and education as a measure of individual-level SES. The multivariable-adjusted effect of neighborhood SES on a 4-meter walking speed test and on grip strength was estimated by least-squares regression.
Results:
Blacks had a slower walking speed, higher grip strength and lower SPPB score compared to whites. Hypertension, higher BMI, and lower education were more prevalent among white and black individuals from low SES neighborhoods, compared to those from high SES neighborhoods. White participants residing in a low SES neighborhood had a 1.1 kilogram (95% CI: 0.3, 1.9) greater grip strength compared to those residing in high SES neighborhoods. Neighborhood SES was not associated with walking speed and SPPB in either whites or blacks. Associations were robust to adjustment for education.
Conclusions:
Individual but not neighborhood-level SES was associated with poorer physical function. The prevalence of adverse clinical comorbidities was higher among both black and white participants living in disadvantaged neighborhoods. Poorer individual, modifiable health and SES measures may be targets for interventions to reduce functional disparities.
Civic Engagement in Retirement and the Socioemotional Experience of Pandemic Time
