OBJECTIVES: Real-world evidence has gained importance in healthcare decision making and the development of health policy globally. This study aimed to identify studies using real-world data to estimate economic burden of disease in Japan.

METHODS: A systematic review was conducted to identify potentially relevant publications. PubMed/EMBASE and ICHUSHI, a Japanese medical literature database, were searched for studies published between February 2012 and February 2018. Studies of interest were those using Japanese healthcare claims database as the study data source, and the outcome of interest was healthcare costs and resource utilization. Clinical trial, case reports and chart review studies were excluded. Two reviewers assessed the studies against inclusion/exclusion criteria, with results reported based on PRISMA guidelines.

RESULTS: This review identified 51 literature using Japanese healthcare claims database to estimate the economic burden of disease. Cancer (9; 18%) and cardiovascular (8; 16%) disease were two most commonly reported disease areas. The diagnosis procedure combination (DPC) claims database was used in 82% of the studies, whereas 18% used health insurance payer claims database. Length of stay and inpatient medical cost were commonly used to evaluate the economic burden of disease. Furthermore 16% of the studies focused on the cost impact of specific medications, while 47% focused on the financial burden of certain health conditions.

CONCLUSIONS: According to Ministry of Health, Labour and Welfare in Japan, the sustainability of Japanese healthcare system is foreseen to be financially challenged due to the super-aging society, where proper distribution of healthcare costs and resource utilization become important. Claims database has a great amount of data, and is able to capture the real-world clinical patterns in multiple institutions. More claims database studies are needed to enrich the evidence on economic analysis of diseases, and to demonstrate the value of health technology.