Individual-level Social Vulnerability and Cognitive Function Among Older Adults in the United States National Health...

Cognitive function is central to healthy aging and independent living. Its impairment burdens individuals and healthcare systems alike. Social vulnerability, shaped by demographic and socioeconomic factors, may be associated with cognitive health, but reliance on community-level assessments limits understanding of individual-level risk.

We analyzed cross-sectional data from 5,989 adults aged ≥60 years in the National Health and Nutrition Examination Survey (NHANES) 1999-2002 and 2011-2014 cycles to examine the association between an individual-level Social Vulnerability Index (iSVI) and cognitive function. We constructed the iSVI by summing six individual-level indicators: income, education, health insurance, employment, housing tenure, and food security. Cognitive performance was measured using the Digit Symbol Substitution Test (DSST). Survey-weighted linear regression estimated associations between iSVI and DSST scores, adjusting for age, sex, race/Hispanic origin, and survey cycle. Effect sizes were interpreted relative to the adjusted association between age and DSST scores.

Higher iSVI was associated with poorer cognitive performance, with each one-unit increase corresponding to a 5.30-point lower DSST score (95% CI -5.71, -4.89). For comparison, each additional year of age was associated with a 1.08-point lower DSST score (95% CI -1.14, -1.03), showing that the DSST difference associated with a one-unit increase in iSVI was similar in magnitude to approximately five years of age-related difference in DSST performance.

Higher individual-level social vulnerability was associated with lower cognitive performance among older US adults. Individual-level vulnerability measures can help identify older adults at risk for poor cognitive outcomes who may benefit from targeted screening and intervention.