Citation

Bae JB, Han JW, Kwak KP, Kim BJ, Kim SG, Kim JL, Kim TH, Ryu SH, Moon SW, Park JH, Youn JC, Lee DY, Lee DW, Lee SB, Lee JJ, Jhoo JH, Kim KW. Aging Dis. 2019; 10(1).

Copyright

(Copyright © 2019, JKL International)

DOI

10.14336/AD.2018.0123

PMID

unavailable

Abstract

Dementia increases the risk of mortality (ROM) in the elderly and estimates of hazard ratio (HR) of dementia for mortality have ranged from 1.7 to 6.3. However, previous studies may have underestimated ROM of dementia due to length bias, which occurs when failing to include the persons with rapidly progressive diseases, who died before they could be included in the study. This population-based prospective cohort study conducted on 6,752 randomly sampled Koreans, aged 60 years or older (the Korean Longitudinal Study on Cognitive Aging and Dementia). Cognitive disorders were evaluated at baseline and 2-year follow-up using the Korean version of the Consortium to Establish a Registry for Alzheimer's Disease Assessment Packet (CERAD-K), and prevalent and incident cases of dementia were identified. The participants' deaths were confirmed through the National Mortality Database of Statistics Korea. We compared the ROM between prevalent and incident dementia, and estimated HR of dementia for mortality using Cox proportional hazards model. Of the 5,097 responders to the 2-year follow-up assessment, 150 participants had dementia from the baseline (prevalent dementia), and 95 participants developed dementia during the 2-year follow-up period (incident dementia). The ROM of participants with incident dementia was about 3 times higher than the ROM of those with prevalent dementia (HR = 3.04, 95% confidence interval [CI] = 1.34-6.91). Compared to cognitively normal participants at both the baseline and 2-year follow-up assessments, the ROM of those with incident dementia approximately 8 times higher (HR = 8.37, 95 % CI = 4.23-16.54). In conclusion, the ROM of dementia using prevalent cases was underestimated due to length bias, and dementia may be much more fatal than previously estimated. In clinical settings, the ROM of dementia warrants the attention of physicians, particularly in recently incident dementia cases. © 2018 Bae JB et al.

Language: en

Keywords

human; suicide; Death; Mortality; female; male; aged; Survival; dementia; depression; prevalence; education; Dementia; posttraumatic stress disorder; mild cognitive impairment; risk factor; alcohol consumption; major clinical study; controlled study; smoking; length of stay; cognitive defect; Alzheimer disease; follow up; cohort analysis; prospective study; DSM-IV; Parkinson disease; neuropsychological test; Article; mortality risk; Mini Mental State Examination; mortality rate; Alzheimer’s disease; Clinical Dementia Rating