Decline in cognitive functioning is associated with a higher mortality risk

Abstract

Objective: This study investigates the association between 5-year change in cognitive functioning and subsequent mortality.

Methods: Four hundred and ninety-three Dutch and Italian men from the Finland, Italy, and the Netherlands Elderly (FINE) Study, born between 1900 and 1920, participated in the present study between 1990 and 2000. Cognitive functioning was measured with the Mini-Mental State Examination in 1990 and 1995, and mortality data were obtained until the year 2000. A proportional hazard analysis was used to investigate the association between 5-year change in cognitive functioning and subsequent 5-year mortality. Adjustments were made for age, education, country, lifestyle factors, prevalence of chronic diseases and, additionally, for baseline cognitive functioning.

Results: Men whose cognition decreased (more than 1 standard deviation) between 1990 and 1995 had a 2-fold higher risk of dying in the following 5 years compared with men whose cognition was stable (adjusted hazard ratio=1.9; 95% confidence interval 1.3-2.7). Mortality risk of men whose cognition improved between 1995 and 2000 was not different from men whose cognition was stable (adjusted hazard ratio=1.1, 95% confidence interval 0.7-1.9).

Conclusion: A decline in cognitive functioning is associated with a higher mortality risk.