Medical Doctors and Dementia: A Longitudinal Study

OBJECTIVE To examine the association between being a medical doctor (MD) and the risk of incident dementia. DESIGN Cohort study. SETTING Olmsted County, Minnesota. PARTICIPANTS A total of 3460 participants (including 104 MDs), aged 70 years or older, of the population-based Mayo Clinic Study of Aging. MEASUREMENTS Participants were randomly selected from the community and had comprehensive cognitive evaluations at baseline and approximately every 15 months to assess for diagnosis of dementia. For participants who withdrew from the follow-up, dementia diagnosis was also assessed using information available in their medical record. The associations were examined using Cox proportional hazards models, adjusting for sex, education, and apolipoprotein E epsilon 4, using age as the time scale. RESULTS MDs were older (vs "general population"), and most were males (93.3%). MDs without dementia at baseline did not have a significantly different risk for incident dementia (hazard ratio = 1.12; 95% confidence interval = 0.69-1.82; P = .64) compared to the general population. CONCLUSIONS Although the study includes a small number of older, mainly male, MDs, it provides a preliminary insight on cognitive health later in life in MDs, while most previous studies examine the health of younger MDs. Larger longitudinal studies are needed to examine these associations and investigate if associations are modified by sex.