Incidence and lifetime risk of dementia and AlzheimerÕs disease in a Southern European population Lobo A, Lopez-Anton R, Santaba´rbara J, de-la-Ca´mara C, Ventura T, Quintanilla MA, Roy JF, Campayo AJ, Lobo E, Palomo T, Rodriguez- Jimenez R, Saz P, Marcos G. Incidence and lifetime risk of dementia and AlzheimerÕs disease in a Southern European population. Objective: To calculate both the incidence rates and the lifetime risk (LTR) of dementia and AlzheimerÕs disease (AD). Methods: A two-phase case-finding procedure was implemented in a cohort of 4057 cognitively intact individuals 55+ years of age living in Zaragoza, Spain, and followed-up at 2.5 and 4.5 years. Age- and sex- specific incidence rates were calculated. A mortality-adjusted, multivariate model was used to document LTRs. Results: The incidence rate of dementia continued to rise after the age of 90 years, but was slightly lower than in North and West European studies. Only a tendency for an increased LTR with age was observed. Thus, LTR was 19.7% for a 65-year-old woman and 20.4% at the age of 85 years, the corresponding figures for AD being 16.7% and 17.6%. The LTR of AD was higher in women and was about twice as high among illiterate individuals when compared with individuals with higher educational levels. Conclusions: The incidence rate of dementia in this Southern European city was slightly lower than in previous studies in North-West Europe. LTR of dementia and AD seems to be slightly increased with age. The association of illiteracy with higher LTR of AD is intriguing. A. Lobo 1,2,3,4 , R. Lopez-Anton 3 , J. Santabµrbara 3,5 , C. de-la-Cµmara 1,2,3,4 , T. Ventura 2,3,4,6 , M. A. Quintanilla 1 , J. F. Roy 3,7 , A. J. Campayo 1,2,3,4 , E. Lobo 1,3,4,5 , T. Palomo 3,8 , R. Rodriguez-Jimenez 3,8 , P. Saz 2,3 , G. Marcos 3,4,5,9 1 Psychiatry Service, Hospital Clínico Universitario, 2 Department of Medicine and Psychiatry, Universidad de Zaragoza, Zaragoza, 3 Centro de Investigación BiomØdica en Red de Salud Mental (CIBERSAM), Ministry of Science and Innovation, Madrid, 4 Instituto AragonØs de Ciencias de la Salud (I+CS), 5 Department of Preventive Medicine and Public Health, Universidad de Zaragoza, 6 Hospital Universitario Miguel Servet, 7 Department of Psychology and Sociology, Universidad de Zaragoza, Zaragoza, 8 Department of Psychiatry, Hospital Universitario 12 de Octubre, Madrid and 9 Medical Records Service, Hospital Clínico Universitario, Zaragoza, Spain Key words: aged; epidemiology; incidence; dementia; Alzheimer disease; risk Dr. Antonio Lobo, Servicio de Psiquiatría, Hospital Clínico Universitario, Planta 3, Avd. San Juan Bosco, 15, 50009 Zaragoza, Spain. E-mail: alobo@unizar.es Accepted for publication June 30, 2011 Significant outcomes • This study suggests that the incidence rate of dementia in a South European city is slightly lower than in most studies reported in North American and North European countries. • The lifetime risk (LTR) of both dementia and AlzheimerÕs disease (AD), calculated with multivariate statistical methods, shows only a slight trend to increase with age and might be a preferred method for communicating disease risk for individuals and for the mass media. • The LTR of AD was about twice as high among illiterate individuals when compared to individuals with higher educational levels. Limitations • We do not have data on ApoE and hospital diagnosis in all cases. • Neuroimaging was available in only a small percentage of cases of dementia. • We only report LTR population estimates, but for any given individual, the estimated LTR would vary with the possible risk factors not controlled in this study Acta Psychiatr Scand 2011: 124: 372–383 All rights reserved DOI: 10.1111/j.1600-0447.2011.01754.x Ó 2011 John Wiley & Sons A/S ACTA PSYCHIATRICA SCANDINAVICA 372