INCIDENCE OF DEMENTIA AND ALZHEIMERS-DISEASE IN ELDERLY COMMUNITY RESIDENTS OF SOUTH-WESTERN FRANCE

Background. Dementia is a growing problem in developed countries. The aim of this paper is to estimate incidence rates of dementia, Alzheime r's disease and vascular dementia in a community population of South-W estern France. Methods. A sample of 2792 subjects was selected and fol lowed-up 1 year and 3 years after the initial screening. At each visit , a standardized questionnaire was administered by trained psychologis ts. Demented subjects were identified using a two-step procedure. The first step consisted of a systematic screening by the psychologist usi ng DSM IIIR criteria for dementia. In the second step, subjects who fu lfilled the DSM IIIR criteria were examined by a neurologist. NINCDS-A DRDA criteria were applied to diagnose Alzheimer's disease. Results. I ncidences of dementia and Alzheimer's disease were estimated at 16.3 a nd 11.4 per 1000 per year, respectively. Incidence estimates increased with age from 2 per 1000 in subjects aged 65-69 years to 74 per 1000 in subjects >90 years. Incidence estimates of Alzheimer's disease show ed the same increase from 0.7 per 1000 to 66 per 1000. Incidences of d ementia and of Alzheimer's disease did not level off with age and were not different between genders.