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Abstract: TH-PO636

Current Status of Treatments for IgA Nephropathy in Japan: A Descriptive Study Using Claims Database

Session Information

Category: Glomerular Diseases

  • 1402 Glomerular Diseases: Clinical, Outcomes, and Trials


  • Matsuzaki, Keiichi, Department of Public Health, Kitasato University School of Medicine, Sagamihara, Japan
  • Ishida, Mami, Department of Medical Informatics and Clinical Epidemiology, Kyoto Prefectural University of Medicine, Kyoto, Japan
  • Kumakura, Tateki, Department of Information and Computer Technology, Tokyo University of Science Graduate School of Engineering, Tokyo, Japan
  • Sozu, Takashi, Department of Information and Computer Technology, Faculty of Engineering, Tokyo University of Science, Tokyo, Japan
  • Suzuki, Hitoshi, Department of Nephrology, Juntendo University Urayasu Hospital, Urayasu, Japan
  • Suzuki, Yusuke, Department of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan

Several questionnaire-based studies have clarified the current status of treatment for IgA nephropathy (IgAN) in Japan. However, there have been few studies on based on the medical claims records. The aim of this study is to clarify the current treatment status for IgAN using the medical claims database in Japan.


Medical claims data were retrieved from JMDC (Tokyo, Japan). To interpret the medical claims data, we used the International Classification of Diseases, Tenth Revision codes (ICD-10) for disease, Anatomical Therapeutic Chemical (ATC) codes for drugs, names of the medical practice for treatment procedure, respectively. First, we extracted the claims who had disease code of IgAN from April 2014 to October 2020 (31282 patients, 469173 receipts). Then, we included the patients aged between 18 and 80 years at the index date with confirmed IgAN diagnosis at least 6 months of continuous insurance coverage/enrollment after the index date. We defined the newly diagnosed IgAN patients as those who underwent renal biopsy and confirmed IgAN more than twice (at least once as the “main disease”). Treatment patterns were categorized by ATC codes and names of the medical practice. Patient who occurred in severe infectious disease was defined as recorded the sequential organ failure assessment score in hospital record.


Among the 4554 included patients, 2200 patients (48.3%) received the corticosteroids. Of those, severe infectious disease occurred in only 8 patients (0.17%). Renin-angiotensin system inhibitors (RAS-I) were used in 2682 patients (58.9%). Women aged 18-29 years had a lower prescription rate of RAS-I (30.2%) than other groups. Of the 805 patients were newly diagnosed IgAN (49.6% men; mean age 44.9), 396 patients (49.2%) underwent the tonsillectomy and 684 patients (85.0%) underwent the corticosteroid therapy including the oral corticosteroid alone respectively. Tonsillectomy with corticosteroid pulse therapy was the most commonly chosen initial treatment procedure (358 patients: 44.5%).


Tonsillectomy with corticosteroid pulse therapy was the standard treatment in Japan.