The ICTUS Study: A Prospective longitudinal observational study of 1,380 AD patients in Europe. Study design and baseline characteristics of the cohort.

The long-term objective of the ICTUS study is to identify milestones in Alzheimer's disease (AD) progression and to develop a model to predict disease course in individual AD patients in Europe. The secondary objectives are to describe the patterns of prescribing, and the socioeconomic impact of AD in Europe. Between 2003 and 2005 1,380 patients with probable AD were recruited in specialised (secondary care) clinics in 12 European countries. Their mean age was 76 years and they had a mean of 8.0 +/- (SD) 4.6 years of education. Thirty-five percent were male. The mean MMSE score was 20.4 +/- (SD) 4.0. Forty-three percent had very mild dementia (CDR 0.5) and 44% had mild dementia (CDR 1). All patients completed baseline evaluation and biannual follow-up is ongoing. The goals of the current study are to describe the specific methods for recruitment in this crosscultural setting and the characteristics of the inception ICTUS cohort, including clinical features, co-morbidity, neuropsychological performance, neuropsychiatric symptoms, functional impairment and social burden