The independent association of social isolation and loneliness with cognitive frailty in Chinese older adults: a cross-sectional study

BACKGROUND: Cognitive frailty (CF) is a distinct clinical phenotype characterized by the co-occurrence of physical frailty and cognitive impairment (excluding Alzheimer's disease and other forms of dementia). Both of social isolation and loneliness are risk factors for cognitive frailty in older adults. However, limited research has explored their independent and combined associations with CF. METHODS: A multi-stage cluster sampling approach was employed to recruit adults aged ≥ 65 years from communities in Ningbo. Basic demographic and health-related information was collected through face-to-face interviews using self-reported questionnaires. CF was defined as the co-occurrence of physical frailty, assessed using the FRAIL scale, and cognitive impairment, evaluated with the Brief Screening Scale for Dementia. Social isolation and loneliness were assessed using standardized questions. Logistic regression was employed to examine their associations with CF, and multiplicative and additive interactions were analyzed to assess potential interaction effects. RESULTS: Overall, 10,151 older adults with a mean age of 72.83 years were included in our study. The prevalence of social isolation, loneliness and CF were 32.3%, 11.8% and 7.22%. After adjusting for covariates, social isolation (odds ratio [OR] = 1.325, 95% confidence interval [CI]: 1.106-1.586) and loneliness (OR = 1.492, 95% CI: 1.196-1.862) were independently associated with CF. However, social isolation and loneliness showed no multiplicative or additive interaction effects on CF (Both P > 0.05). CONCLUSION: Social isolation and loneliness are independently associated with CF in Chinese older adults, highlighting the necessity of implementing effective and feasible interventions to concurrently address both factors in the prevention of CF among the elderly population.