Objective: Cognitive impairment among the elderly has been linked to mortality in studies of clinical populations. The purpose of this study was to examine the mortality risk associated with cognitive impairment among elderly populations in the community.
Methods: Cognitive impairment and other social and health factors were assessed in 1855 elderly community residents. This sample was reinterviewed periodically to assess changes in health and survival.
Results: At baseline 33% of the sample were mildly impaired and 8% were severely impaired. Across a 48-month observation period the survival probability was .85 for the cognitively unimpaired, .69 for the mildly impaired, and .51 for severely impaired respondents. When adjustments were made for the effects of other health and social covariates, severely impaired persons were twice as likely to die as unimpaired persons. Those who were mildly impaired were also at an increased risk.
Conclusions: Other investigators have found that cognitive impairment is a significant predictor of dementia. We found that it is a significant predictor of mortality as well. Early detection of impaired cognition and attention to associated health problems could improve the quality of life of these older adults and perhaps extend their survival.