Prevalence of dementia and major dementia subtypes in Spanish populations: A reanalysis of dementia prevalence surveys, 1990-2008
1 National Centre for Epidemiology, CIBERNED and Alzheimer' Disease Research Unit, Carlos III Institute of Public Health, Madrid, Spain
2 Primary Care Administration, Segovia, Spain
3 Neurology Unit, Salnés Hospital, Pontevedra, Spain
4 Department of Medicine and Psychiatry, Zaragoza University, Zaragoza, Spain
5 Neurology Unit, Segovia Hospital, Segovia, Spain
6 Madrid Regional Health Authority, Madrid, Spain
7 Dementia Diagnosis and Treatment Unit, Neurology Department, Bellvitge University Teaching, Spain
8 Llodio Health Center, Day Medical Center, Oroityu-Getxo-Vizcaya, Spain
9 Psychiatry Department, University of Santiago de Compostela, Spain
10 Neurology Unit, Virgen del Camino Hospital, Pamplona, Spain
11 Dementia Unit. Hospital Santa Caterina, Institut d'Assistència Sanitària, Salt, Spain
12 Barcelona Hospital, Barcelona, Spain
13 Geriatrics Unit. Virgen del Valle Geriatric Hospital., Toledo, Spain
14 Neurology Service, Cruces Hospital, Day Medical Center, Oroityu-Getxo-Vizcaya, Spain
15 Neurology Department, 12 de Octubre University Teaching Hospital, Madrid, Spain
16 Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
17 Neurology Department, Bidasoa-Hondarribia Hospital, Guipúzcoa, Spain
BMC Neurology 2009, 9:55 doi:10.1186/1471-2377-9-55Published: 19 October 2009
This study describes the prevalence of dementia and major dementia subtypes in Spanish elderly.
We identified screening surveys, both published and unpublished, in Spanish populations, which fulfilled specific quality criteria and targeted prevalence of dementia in populations aged 70 years and above. Surveys covering 13 geographically different populations were selected (prevalence period: 1990-2008). Authors of original surveys provided methodological details of their studies through a systematic questionnaire and also raw age-specific data. Prevalence data were compared using direct adjustment and logistic regression.
The reanalyzed study population (aged 70 year and above) was composed of Central and North-Eastern Spanish sub-populations obtained from 9 surveys and totaled 12,232 persons and 1,194 cases of dementia (707 of Alzheimer's disease, 238 of vascular dementia). Results showed high variation in age- and sex-specific prevalence across studies. The reanalyzed prevalence of dementia was significantly higher in women; increased with age, particularly for Alzheimer's disease; and displayed a significant geographical variation among men. Prevalence was lowest in surveys reporting participation below 85%, studies referred to urban-mixed populations and populations diagnosed by psychiatrists.
Prevalence of dementia and Alzheimer's disease in Central and North-Eastern Spain is higher in females, increases with age, and displays considerable geographic variation that may be method-related. People suffering from dementia and Alzheimer's disease in Spain may approach 600,000 and 400,000 respectively. However, existing studies may not be completely appropriate to infer prevalence of dementia and its subtypes in Spain until surveys in Southern Spain are conducted.