The prevalence of mild cognitive impairment by aspects of social isolation

This study describes the prevalence of mild cognitive impairment (MCI) across different aspects of social isolation among adults 65 years or older.

In this cross-sectional study, we utilized the Wave 3 data from the National Social Life, Health, and Aging Project (NSHAP). MCI was defined as a Montreal Cognitive Assessment (MoCA) score less than 23. Prevalence of MCI was calculated for above and below average social disconnectedness (SD), perceived isolation (PI), and demographic variables age, gender, race/ethnicity, education, and household income.

The overall prevalence [and 95% confidence interval] of MCI was 27.5% [25.5-29.6]. The high prevalence of MCI was found in those who had above average SD (32.0% [29.1-34.9]), above average PI (33.3% [29.7-36.8]), were older in age (43.1% [38.9-47.3]), male (28.7% [25.9-31.5]), Black (61.1% [52.5-69.6]), had less than a high school education (66.3% [58.9-73.8]), or were in the lowest income group (46.2% [39.7-52.7]). Those with above average SD or PI had a higher prevalence of MCI in almost all demographics, compared to those with below average SD or PI. Those who were Black or African American or had less than a high school education did not have a greater prevalence of MCI when SD was above average.

This current study adds to the body of literature that links SD and PI to MCI and sheds light on the possible existing socio-demographic disparities. Groups with greater than average SD or PI tend to have a higher prevalence of MCI. Further studies are needed to establish a causal association of SD and PI with MCI.