Systematic review to estimate the prevalence of inflammatory rheumatic diseases in Germany

This study aimed to update the prevalence estimates of inflammatory rheumatic diseases (IRD) in Germany.

A systematic literature search in PubMed and Web of Science (last search 08 November 2022) identified original articles (regional and nationwide surveys and claims data analyses for arthritides, connective tissue diseases, and vasculitides) on prevalences for the period 2014-2022. Data sources, collection period, case definition, and risk of bias are reported. Prevalences were estimated from available national data, with consideration of international data.

Screening by two authors yielded 263 hits, of which 18 claims data analyses and 2 surveys met the inclusion criteria. Prevalences ranged from 0.42 to 1.85% (rheumatoid arthritis), 0.32-0.5% (ankylosing spondylitis), 0.11-0.32% (psoriatic arthritis), 0.037-0.14% (systemic lupus erythematosus), 0.07-0.77% (Sjögren's disease/sicca syndrome), 0.14-0.15% (polymyalgia rheumatica, ≥ 40 years), 0.04-0.05% (giant cell arteritis, ≥ 50 years), and 0.015-0.026% (ANCA-associated vasculitis). The risk of bias was moderate in 13 and high in 7 studies. Based on the results, we estimate the prevalence of IRD in Germany to be 2.2-3.0%, which corresponds to approximately 1.5-2.1 million affected individuals. The prevalence of juvenile idiopathic arthritis was reported to be around 0.10% (0.07-0.10%) of 0-18-year-olds, corresponding to about 14,000 children and adolescents in Germany.

This systematic review shows an increase in the prevalence of IRD in Germany, which is almost exclusively based on claims data analyses. In the absence of multistage population studies, the available data are, overall, uncertain sources for prevalence estimates, with a moderate to high risk of bias.