Very Mild to Severe Dementia and Mortality: A 14-Year Follow-Up – The Odense Study

Abstract

Background/Aims: To examine the mortality of very mildly to severely demented persons compared to nondemented persons. Methods: Participants in a randomly drawn population-based cohort study on dementia were followed for 14 years from 1992 to 2006. Participants were examined at baseline (3,065 nondemented and 234 prevalent demented), after 2 years (2,286 nondemented and 145 incident demented) and again after 5 years (1,669 nondemented and 124 new cases of dementia). Causes of death were ascertained in 884 nondemented and 286 demented participants. Survival for demented compared to nondemented persons was analyzed with the Cox proportional hazards model with time-dependent covariates adjusted for gender and age. Results: The hazard ratio of death (95% confidence interval) increased from 1.82 (1.55–2.14) for the very mildly demented to 9.52 (6.60–13.74) for the severely demented subjects. The demented participants died significantly more often of neurological causes other than dementia and of pneumonia than the nondemented participants. No other significant differences in causes of death were found. Conclusion: Dementia increased the risk of death. Even in the very early stages of dementia the risk of death was increased.