AbstractBackgroundAlzheimer’s disease (AD) is a major public health problem. Although donepezil is used as a first‐line pharmaceutical treatment for AD, studies from various countries have reported low continuation rates. However, the only available data from Japan are from post‐marketing observational study reports. This study investigated the continuation rates of newly prescribed donepezil among AD patients in Japan.MethodThe study was conducted using health care claims data and long‐term care claims data from 17 Japanese municipalities participating in the Longevity Improvement & Fair Evidence (LIFE) Study. The study period was from April 2014 to October 2021, and the study population comprised patients who had been newly prescribed donepezil after receiving a diagnosis of AD. The treatment discontinuation was defined as a gap of ≥61 days between the last donepezil prescription and subsequent donepezil, cholinesterase inhibitors, or memantine prescription. Kaplan‐Meier curves were plotted to estimate the duration (days) from the start of a new prescription of donepezil until discontinuation, and patients were censored at the end of the observation period or death. The treatment continuation rates were also analyzed according to the patients’ certified long‐term care needs levels (ranging from levels 1‐5) at the time of the initial prescription.ResultWe analyzed 20,474 patients (mean age: 82.2 years, women: 65.7%) with a mean follow‐up duration of 483 days. The treatment continuation rates at 30 days, 90 days, 360 days, and 540 days after initial prescription were 89.1%, 79.4%, 64.5%, and 58.3%, respectively. By excluding patients with long‐term care needs levels 3‐5, we analyzed 18,924 patients with lower care needs levels (mean age: 82.0 years, women: 65.4%); their treatment continuation rates were almost identical to those of all patients (<1% difference). Within 60 days of donepezil discontinuation, only 2.9% and 3.1% of patients had been switched to galantamine and rivastigmine, respectively.ConclusionThe AD patients showed a rapid discontinuation of donepezil and subsequent AD treatments by 90 days, and approximately 40% had ceased this therapy after 1.5 years. In view of the limited pharmaceutical options available for AD in Japan, this finding emphasizes the need for AD preventive measures in the pre‐clinical stage.