OBJECTIVES: There is a lack of long-term prospective data to document the economic burden (direct and indirect costs) of Alzheimer’s disease (AD), especially in moderate AD where disease management becomes more complex. The EVOCOST study aims to describe and analyse the healthcare resource use and costs associated with clinical evolution in a cohort of moderate AD patients in routine medical practice in Spain. METHODS: The EVOCOST study is a prospective 12-month multicentre cohort study recruiting community-dwelling moderate AD patients in Spain. Healthcare resources (specialist, general practitioner and nurses visits, hospitalisations and emergency room visits, antidementia drugs and institutionalisation) and non-healthcare resources (caregiver’s time for care and supervision) were collected retrospectively. Total costs over the entire 12-month study follow-up were calculated. Costs over the 3 months preceding baseline and the end of follow-up were compared. RESULTS: A total of 209 patients were included at baseline, 76.1% of them were women, with a mean age of 78.4 years and a mean MMSE of 15.2. Over the entire 12-month study follow-up, the mean monthly cost per patient was €1016 (annual cost €12197). The major cost driver was the informal caregiver time dedicated to patient supervision and care (€852, 84% of total cost). Other costs were as follows: antidementia drugs (€88, 9%), hospitalisation and emergency room visits (€31, 3%), visits (€26, 3%) and institutionalisation (€20, 2%).The mean monthly cost per patient increased significantly during the 12-month study follow-up from €902 to €1074 (Dcost=+19%, p<0.001), mainly due to the increase in caregiver time. CONCLUSIONS: Management of community-dwelling moderate AD patients in Spain is associated with a high monthly cost (> €1000/month). The main cost driver is by far the caregiver time which is not reimbursed by health insurance. The EVOCOST study results illustrate the economic burden of Alzheimer’s disease on patients’ caregivers.