Late-life cynical distrust, risk of incident dementia, and mortality in a population-based cohort

We investigated the association between late-life cynical distrust and incident dementia and mortality (mean follow-up times of 8.4 and 10.4 years, respectively) in the Cardiovascular Risk Factors, Aging and Dementia Study.

Cynical distrust was measured based on the Cook-Medley Scale and categorized into tertiles. Cognitive status was evaluated with a 3-step protocol including screening, clinical phase, and differential diagnostic phase. Dementia was diagnosed according to DSM-IV criteria. Complete data on exposure, outcome, and confounders were available from 622 persons (46 dementia cases) for the dementia analyses and from 1,146 persons (361 deaths) for the mortality analyses. Age, sex, systolic blood pressure, total cholesterol, fasting glucose, body mass index, socioeconomic background, smoking, alcohol use, self-reported health, and APOE genotype were considered as confounders.

Cynical distrust was not associated with dementia in the crude analyses, but those with the highest level of cynical distrust had higher risk of dementia after adjusting for confounders (relative risk 3.13; 95% confidence interval [CI] 1.15-8.55). Higher cynical distrust was associated with higher mortality in the crude analyses (hazard ratio 1.40; 95% CI 1.05-1.87) but the association was explained by confounders (adjusted hazard ratio 1.19; 95% CI 0.86-1.61).

Higher cynical distrust in late life was associated with higher mortality, but this association was explained by socioeconomic position, lifestyle, and health status. Association between cynical distrust and incident dementia became evident when confounders were considered. This novel finding suggests that both psychosocial and lifestyle-related risk factors may be modifiable targets for interventions. We acknowledge the need for larger replication studies.