Validation of a social deprivation index and association with cognitive function and decline in older adults.

ABSTRACT

OBJECTIVES: Previous work using a US sample has shown that an index of social deprivation (SoDep Index) is associated with cognitive functioning and decline in older adults. This study aimed to replicate these findings using a European sample (Survey of Health, Ageing and Retirement in Europe, SHARE). DESIGN: We analyzed data of 51,630 respondents aged 50 years and older (M 63.5 years, standard deviation [SD] 9.1) with at least two cognitive assessments (follow-up M 6.06 years, SD 3.86). Cognitive scores were transformed to Z-scores. Multiple growth curve modeling was used to model cognitive status and decline as predicted by the SoDep Index. In a sensitivity analysis, we constructed a new SoDep Index (SoDep Indexnew) including further social deprivation domains. RESULTS: Adjusting for covariates, a unit increase in SoDep Index was associated with a cognitive score of 0.037 SDs smaller (p < .001) and a decline 0.003 SDs per year faster (p < .001). Of the covariates, depressive symptoms, chronic disease burden, male gender, and widowhood were also associated with poorer cognition. Being divorced was associated with better cognition. Sensitivity analysis confirmed findings. Compared to the SoDep Index, the SoDep Indexnew showed a more pronounced association with both cognition and cognitive decline. CONCLUSIONS: We were able to replicate results showing an association between SoDep Index and cognitive function and decline. The sensitivity analysis further emphasizes the relevance of financial security. This strengthens the implication that preventing social deprivation can contribute to reducing the dementia burden by raising cognitive functioning in the older population. The findings are relevant to policy-makers and health care practitioners.