Impaired health status is associated with an increased risk of mild cognitive impairment

Objective: To investigate associations of self-reported health status and Mild Cognitive Impairment (MCI). Background: MCI, a transitional stage between normal aging and Alzheimer's disease, has been associated with subjective concerns about cognitive function. MCI may result from impaired health status. Design/Methods: A sampling frame of all Olmsted County, MN, residents aged 70 – 89 years on October 1, 2004, was constructed using the records-linkage system of the Rochester Epidemiology Project. Random samples of persons within age and sex categories were invited to participate in the study. Participants were evaluated using the Clinical Dementia Rating Scale, Short Test of Mental Status, a neurologic examination, and neuropsychometric testing. A consensus panel of neurologists and neuropsychologists reviewed information on participants to reach a diagnosis of normal cognition, MCI, or dementia. Self-reported perception of health status was collected via a structured interview. Results: We identified 295 MCI cases and 590 age- and sex-matched controls with normal cognition. A total of 62/295 (21.0%) cases reported their health status as fair or poor compared to 63/590 (10.7%) controls. In conditional logistic regression models adjusted for years of education, the Odds Ratio (OR) of MCI was 2.32 (95% CI = 1.53, 3.50) in subjects who reported fair or poor health status and 1.26 (95% CI = 0.92, 1.74) in subjects who reported good health status, compared to subjects who reported very good or excellent health status. Conclusions/Relevance: Subjects aged 70 – 89 years old with fair or poor health status may be at increased risk of MCI.