Does cognitive impairment moderate the relationship between social isolation and anxiety? A 5-year longitudinal study of a nationally representative sample of community residing older adults.

BACKGROUND: Anxiety is common in older adults and social isolation is one of the leading factors associated with their anxiety. However, what is unknown is how the relationship between social isolation and anxiety differs by cognitive status. Therefore, this study was conducted to (1) compare the level of social isolation and anxiety in older adults who developed probable dementia and mild cognitive impairment (MCI) to those who maintained normal cognitive function over 5 years; and (2) determine if cognitive impairment moderates the relationship between changes in social isolation and changes in anxiety over 5 years. METHODS: A secondary data analysis was conducted using the National Social Life, Health, and Aging Project (NSHAP): Wave 2 (2010-2011) and Wave 3 (2015-2016). The participants were categorized into three groups: Participants who developed probable dementia over 5 years (4.3%), developed probable MCI (19.1%), or maintained normal cognitive function (76.6%). Weighted linear regression analyses with a group interaction were used to examine the moderating effect of cognitive impairment on the relationship between changes in social isolation and anxiety. RESULTS: At the 5-year follow up, there were statistically significant differences in social isolation between the three groups (p = 0.043). Regression analyses showed that increased social isolation over time was related to increased anxiety over 5 years regardless of cognitive status after controlling for covariates (p = 0.017). CONCLUSIONS: The relationship between social isolation and anxiety was a universal phenomenon regardless of cognitive status. Tailored interventions targeting both people with or without cognitive impairment are needed to lessen social isolation and anxiety.