Prevalence and incidence of Alzheimers disease and other dementing disorders in Pylea, Greece

Abstract

We investigated the prevalence and incidence of dementing disorders in the city of Pylea, Greece, using a door-to-door three-phase approach, and explored the relationship between age and gender. From the initial cohort of 704-subjects, 112-subjects (15.9 percent) were excluded because they had moved out of town or could not be traced, 102-subjects (14.4 percent) died before the time of actual contact, and 110-subjects (15.6 percent) refused to be contacted. We were able to visit and examine 380-subjects (54 percent); each of them were administered the MMSE by one of three nurses and the CAMCOG by one of three physicians. We selected January 1, 1993, as the study prevalence day. Using specified diagnostic criteria, NINCDS-ADRDA and DSMIIIR, the study neurologists extensively investigated 118 from 380-subjects, who screened positive on MMSE (MMSE < 23) and CAMCOG (< 65). We found 35-subjects affected by dementia, 20 had Alzheimer's disease (AD), 11 had vascular or mixed dementia and four had secondary dementia (one Parkinson's disease, one Vitamin B12 deficiency, and two had Tumors). The estimated annual incidence rate for all forms of dementia, after correction for ageing of the samples was 57/1,000 persons aged > 70, made up of dementia of Alzheimer type (39.9/1,000), vascular dementia (13.9/1,000) and other forms (3.5/1,000). The prevalence of both dementia and AD increased steeply with advancing age and was consistently higher in women. The incidence of dementia increases with age, even in the oldest age groups and women have a higher risk of developing dementia than men. AD was the most common type of dementia. Our prevalence and incidence figures for dementia and AD are almost similar to those previously reported in Europe, the United States and Canada.