Mortality in Alzheimer's disease: a comparative prospective Korean study in the community and nursing homes

Abstract

To test a hypothesis that Alzheimer's disease (AD) patients in nursing homes have higher mortality rate than do AD patients cared for at home and to investigate the predictors of mortality in AD. A one-year prospective follow-up in Korea. A total of 252 subjects (107 in the community, 145 in a nursing home) were longitudinally assessed at baseline, 6 months and 12 months. Mortality rates between groups were compared using Kaplan-Meier curve and log-rank statistics. Relative risks (RRs) were examined by the Cox proportional hazards model. Overall one-year mortality rate in AD was 18.7%. There was no statistically significant difference in AD mortality rates between patients who continued to be cared for at home and AD patients in the nursing home. After controlling for age, group (nursing home or community), severity of dementia, Mini-Mental State Examination (MMSE) score and vascular risk factors, there remained advanced age [risk ratio (RR) 1.06; 95% confidence interval (CI) 1.04-1.09], advanced Global Deterioration Scale (GDS) stage (RR 1.98; 95% CI 1.41-2.77), longer duration of AD (RR 1.07; 95% CI 1.04-1.10), presence of tactile hallucination (RR 1.74; 95% CI 1.08-2.78), wandering (RR 1.89; 95% CI 1.18-3.02) and depression (RR 1.07; 95% CI 1.02-1.10) as independent predictors of mortality in AD. This may be the first study demonstrating presence of tactile hallucination as a strong predictor of mortality in AD. This study does not support the hypothesis of a higher AD mortality rate in nursing homes.