Comorbidity and drug use in cognitively impaired elderly living in long-term care.

Cognitive impairment is associated with an increased mortality in older people. The prevalence and impact of comorbidity on functional status and mortality of demented patients has not been fully elucidated. Using a population-based data set, we describe the prevalence of cognitive impairment, functional status, principal comorbid conditions and 1-year survival for over 300,000 patients admitted to the nursing homes in five US states. Sixty-one percent of patients have some level of cognitive impairment, and this correlates with the degree of physical frailty. Severer cognitive impairment is associated with a higher mortality rate. Yet, patients with cognitive impairment appear to have fewer comorbid conditions and are less likely to receive medications and special treatments than residents with normal cognitive status. Additional studies are needed to understand whether demented patients may paradoxically be considered healthier or, instead, are only neglected.