Anti-dementia drugs: a descriptive study of the prescription pattern in Italy.

Introduction: Acetylcholinesterase inhibitors (AChEIs) and memantine are currently the only anti-dementia drugs (ADDs) approved for treating Alzheimer's disease (AD) in Italy. This nationwide study aims to characterize dementia drug utilization in a population > 65 years, during 2018-2020.

Methods: Different administrative healthcare databases were queried to collect both aggregate and individual data.

Results: ADD consumption remained stable throughout the study period (~ 9 DDD/1000 inhabitants per day). AChEI consumption was over 5 DDD/1000 inhabitants per day. Memantine consumption was nearly 4 DDD/1000 inhabitants per day, representing 40% of ADD consumption. The prevalence of use of memantine represented nearly half of ADD consumption, substantially unchanged over the 3 years. Comparing the AD prevalence with the prevalence of ADDs use, the gap becomes wider as age increases. In 2019, the proportion of private purchases of ADDs was 38%, mostly represented by donepezil and rivastigmine. In 2020, memantine was the only ADD with an increase in consumption (Δ% 19-20, 1.3%).

Discussion: To our knowledge, this study represents the first attempt to investigate the ADD prescription pattern in Italy with a Public Health approach. In 2019, the proportion of ADD private purchases point out several issues concerning the reimbursability of ADDs. From a regulatory perspective, ADDs can be reimbursed by the National Health System only to patients diagnosed with AD; therefore, the off-label use of ADDs in patients with mild cognitive impairment may partially explain this phenomenon. The study extends knowledge on the use of ADDs, providing comparisons with studies from other countries that investigate the prescription pattern of ADDs.