RESUMO
PURPOSE: Alzheimer's disease (AD) evolves over about ten years with cognitive decline that can be considered as linear. Comorbidities are frequent in geriatric population. The major objective of this study is to determine whether comorbidity influences natural history of AD. MATERIALS AND METHODS: This is a prospective, multicentric French study (REAL.FR) of a cohort of ambulatory patients suffering from AD from a mild to a moderately severe stage, with a Mini-Mental State between 10 and 26, and followed with a caregiver. We evaluated the comorbidities and they were quantified using the Charlson index. RESULTS: We analysed 579 AD patients enrolled between April 2000 and June 2002. Majority of patients were women (72%). Average age and MMS average score were respectively 77.4 +/- 7.1 and 20.1 +/- 4.5. Cardiovascular diseases were the most frequent comorbid conditions (34%), before sensorial handicap (23%), and neurological diseases (18%) apart from dementia. Four AD patients groups differed according to the comorbidities figures, from none to more than three (maximum 8). Average Charlson index was 1.5 +/- 0.9. CONCLUSION: The follow-up of the four AD patients groups, differentiated by the comorbidities figures, should allow to precise the influence of comorbidities on the AD evolution. Charlson index could be used to quantify the comorbidities in the cohort's follow-up. However, this index, validated in a cohort of cancer patients, show limits for its use in geriatric population.