Real-world trends in acute viral hepatitis in Japan: A nationwide questionnaire-based survey.

Abstract

The actual incidence of acute viral hepatitis in Japan remains unclear. We aimed to investigate trends in the incidence of acute hepatitisB and C infections in Japan. A nationwide, multicenter, retrospective questionnaire-based survey was conducted. Participating hospitals received questionnaires through nationwide geographically distributed regional core centers certified as specialists in hepatitis treatment. The questionnaire included hospital size and the number of patients diagnosed with acute hepatitisB or C during each fiscal year (FY) from 2015 to 2022. The sex distribution in each FY was also documented. Comparisons were made before and during the COVID-19 era (2015-2019 vs. 2020-2022), and between populous and non-populous prefectures. Responses to the questionnaires were obtained from 127 institutions in 29 prefectures covering eight regions in Japan. A median of 127.0 patients with acute hepatitisB (interquartile range [IQR] 106.5-131.8 patients) were reported during each FY, and the incidence significantly decreased during the fiscal years 2020-2022 compared with the fiscal years 2015-2020 (median 96.0 [IQR 91.0-103.0] patients vs. 131.0 [IQR 128.0-134.0] patients; p=0.03). A median of 10.0 (IQR, 7.8-13.5) patients were reported with acute hepatitisC during each FY. The proportions of men in acute hepatitis B and C were significantly higher in populous prefectures. Populous prefectures had a higher proportion of men among viral hepatitis patients than non-populous prefectures. Estimating the high-risk populations in each area could provide insights to advance the elimination of viral hepatitis.