#3364 Epidémiologie des cas d'IgAN en France : évaluation à partir des bases de données médico-administratives hospitalières en France (PMSI)

Abstract Background and Aims IgA nephropathy (IgAN) is the most common primary glomerulopathy, with incidence varying from country to country. In France, epidemiological data are available, but only at the level of individual centers or regions. In addition to these clinical data, medico-administrative databases are a relevant source of data on a national scale. The aim of this study was to develop an algorithm to identify cases of IgAN from French hospital medico-administrative databases (PMSI). Method All patients hospitalised with at least one ICD-10 code related to IgA-deposited nephropathy between January 1, 2015 and December 31, 2022 were included from the PMSI database. IgAN diagnosis being confirmed by a renal biopsy, the related codes were searched for in a 2-year retrospective period before the appearance of the first IgAN code. Finally, a set of criteria was applied to identify and exclude patients with biopsies related to other pathologies (renal tumour, as well as to differentiate secondary IgAN (vasculitis, cirrhosis, connective tissue diseases, inflammatory bowel disease, spondyloarthropathy)). Results Between 2015 and 2022, 8,467 patients were identified with a diagnosis code related to IgA deposits. Of these patients, 3,213 (37.9%) had undergone a renal biopsy in the previous 2 years. Patients had an average age of 47 ± 2 years and 71.5% were male. A total of 1,653 patients (19.5%) had a biopsy procedure associated with another pathology, the main cause of secondary IgAN being IgA vasculitis (10% of patients). Conclusion This preliminary study has made it possible to develop an algorithm for identifying IgAN cases using PMSI data. In order to assess the performance of the algorithm, a validation study of the identification of cases will have to be carried out using clinical and/or histological data to confirm the identification of these patients.