In each of the 7 French areas that should be involved, patients aged 75 years and over from three different sectors will be included: the geriatric consultation unit (60%) and two kinds of nursing homes, private (20%) and state (10%). Outpatients will be included in chronological order; patients in nursing homes will be included at random. The patients and their families will be asked about the treatments received on the day of inclusion. The inclusion period will extend over a year. The investigating practitioners will be asked to fill in a questionnaire reporting the main clinical data, adverse effects occurrence, and information on the treatment given.

Inclusion Criteria:

• Patients aged 75 years and over identified as having Alzheimer disease and who have been treated for more than 3 months with anticholinesterase and/or memantine

Exclusion Criteria:

• Patients with decompensated chronic condition or acute phase disease

Patient of 75 and more years old affected by the Alzheimer's disease