Wide difference in biologics usage and expenditure for the treatment of patients with rheumatoid arthritis in each prefecture in Japan analyzed using "National Database of Health Insurance Claims and Specific Health Checkups of Japan".

To analyze the biologics usage and expenditure for the treatment of patients with rheumatoid arthritis (RA) in each prefecture throughout Japan using the national open database, the Ministry of Health, Labour and Welfare of Japan disclosed; in Oct 2016, the data of the top 30 most-frequently prescribed drugs during a 1-year period from April 2014 to March 2015 in each prefecture in Japan, along with the patients' age and sex. Seldom-used drugs were excluded. We picked up only biologics for the present study. The total expenditure on biologics used in each prefecture was correlated with the population thereof. However, there was a big difference, up to ~ twofold, in the average expenditure used for an RA patient: highest in Toyama and lowest in Wakayama. There was also a big difference, ~ 4.5-fold, in the number of rheumatologists/1000 RA patients, highest in Kyoto and lowest in Aomori. The average expenditure used for an RA patient was correlated with the number of rheumatologists in the western part of Japan. Etanercept seemed to be used most frequently to Japanese RA patients followed closely by infliximab. Abatacept was used more frequently to the elderly than other biologics. There was a big difference in the number of rheumatologists and expenditure on biologics for the treatment of an RA patient among prefectures in fiscal 2014. Factors that brought this unevenness need to be scrutinized for universal implementation of good RA care throughout Japan, where there are uniform health insurance system and free access to rheumatologists.