Incidence of dementia and other psychiatric conditions in the elderly: Zaragoza Study.

A prevalence study of dementia and other psychiatric disturbances in the geriatric population of Zaragoza, Spain, has been completed. Our group is now planning an incidence study. The design comprises a baseline study (cross-sectional study of prevalence) and a follow-up 2 years later of the cohort of non-demented elderly. Both studies have two phases: the first one for screening, and the second one for the clinical diagnosis. We use the Spanish versions of the Geriatric Mental State GMS-AGECAT package, the History and Aetiology Schedule (HAS) and the Mini-Mental Status Examination (MMSE) as screening instruments. For the final diagnosis, a full protocol will be used, and the demented cases will be diagnosed according to DSM-IIIR, ICD-10 and Project Criteria. A case-control study of incident cases of dementia will be incorporated into the follow-up. Other methodological issues are analyzed.