Seasonal Variation of Drug Prescription Rate for Overactive Bladder in Men Based on National Health Insurance Claims Data, 2012-2016

Abstract

Purpose: Overactive bladder (OAB) symptoms might be affected by weather, but only a few clinical studies have investigated this issue. We investigated seasonal variations in OAB-drug prescription rate (DPR) in men using nationwide claims data in Korea.

Methods: A total of 2,824,140 men aged over 18 years were included from the Health Insurance Review and Assessment service - National Patient Sample data between 2012 and 2016. Depending on the monthly average temperature, the seasons were divided into 3 groups, namely, hot (June, July, August, and September), intermediate (April, May, October, and November), and cold (January, February, March, and December) seasons. OAB-DPR was estimated using the claims data, and differences in its rate were examined among the 3 seasonal groups.

Results: The overall OAB-DPR was 1.97% (55,574 of 2,824,140). The OAB-DPR were 0.38%, 0.63%, 0.92%, 1.74%, 4.18%, 7.55%, and 9.69% in the age groups of under 30, 30s, 40s, 50s, 60s, 70s, and over 80 years, respectively; thus, the prescription rate increased with age (P<0.001), with a steeper increase after 60 years of age. OAB-DPR was 1.02% in the hot season, 1.19% in the intermediate season, and 1.27% in the cold season, with significant differences among the 3 seasonal groups (P<0.001). These seasonal variations persisted in the subgroup analysis in each age decade (P<0.001).

Conclusion: OAB-DPR varied with seasons and was significantly higher in the cold season than in the hot season, suggesting that cold weather may affect development and aggravation of OAB symptoms in men.

Keywords: Men; Seasons; Urinary bladder, Overactive.

Fig. 1.

Case extraction diagram. HIRA, Health Insurance Review and Assessment Service; NPS, National Patient Sample; OAB, overactive bladder.

Fig. 2.

Drug prescription rate for overactive bladder in men according to seasons in each age decade.