Prevalence and European comparison of dementia in a ≥75-year-old composite population in Spain

Objectives - To estimate dementia prevalence in Spain. Materials and methods - Nine probabilistic and geographically defined samples participated. A screening design based on the MMSE was implemented. Positively screened individuals underwent clinical evaluation. The total number of cases in Spain was estimated. Prevalence was confronted to that of other European countries. Results - Five hundred and forty-six persons aged >= 75 participated, 49 had dementia (35 with Alzheimer's disease [AD], 10 with vascular dementia [VD], 4 other; 25 first diagnosed in the study). Age- and sex-adjusted prevalence and estimated nationwide cases were 7.5% (95% CI 5.4-9.7), 5.6 (95% CI 3.7-7.5) and 1.4 (95% CI 0.5-2.3), and 290,000 (95% CI 208,000-372,000), 214,000 (95% CI 141,000-288,000) and 54,000 (95% CI 20,000-88,000) for dementia, AD and VD, respectively. Conclusions - Dementia prevalence in Spain is comparable to other European populations, while a high number of undiagnosed cases live in the community. The potential impact of Mediterranean diet, hypertension control and decreasing vascular risk factors is discussed.