Introduction: Currently, there are no studies on changes in health problems due to population aging in Japan. This study was conducted to estimate the changes by comparing the present health problems using the International Classification of Primary care second edition (ICPC-2) with a previous study.

Methods: We conducted a retrospective open cohort study on a rural island in Okinawa. We classified health problems of all patients using ICPC-2, and compared the data with a previous study using the International Classification of Health problems in Primary care-2 defined (ICHPPC-2 defined) from 1990.

Result: The total number of visits to the clinic was 4660 per year (age 0-14 years, n=828; age 15-64, n=2146; age 65 or older, n=1688). In 2015, the frequency of musculoskeletal, skin and general, and unspecified problems was higher. The number of health problems contained within the top 50% of all health problems, which is an indicator of the comprehensiveness of practice, was higher in the previous study.

Conclusion: The present study suggested that orthopedic and dermatological disorders increased, and greater comprehensiveness of practice is needed.