[Differences between women and men in rheumatic systemic diseases with lung involvement]

Biological sex has a significant impact on the prevalence and course of lung involvement and inflammatory rheumatic diseases (IRD). However, data and analyses addressing this relationship are lacking for Germany.

In a retrospective analysis, data from the German Federal Statistical Office were evaluated using hospital discharge diagnoses coded according to the International Classification of Diseases (ICD-10) from 2005 to 2023. Frequency, temporal trends, and distribution were analysed separately for women and men. Eleven rheumatologic diseases as primary diagnoses were included: rheumatoid arthritis (M05, M06), connective tissue diseases (M32-M35), and ANCA-associated vasculitis (M30.1, M31.3, M31.7). Each was combined with five secondary diagnoses indicating pulmonary involvement (J84.1, J84.8, J84.9, J99.0*, J99.1*).

Over the 19-year observation period, the total number of hospitalizations for women with IRD (n = 734,167; 68%) exceeded that of men (n = 349,806; 32%). The absolute number of cases with lung involvement associated with IRD was also higher in women (n = 88,936) than in men (n = 52,523). However, the relative proportion of lung involvement among patients with IRD was higher in men compared to women (15% vs. 12%). In both sexes, case numbers increased steadily over the study period, with a transient decline in 2020. The rise in cases with lung involvement among patients with IRD over time was more pronounced in men.

The number of hospitalized patients with lung involvement secondary to IRD has increased continuously over the past 19 years. Male patients with IRD appear to have a higher risk of developing lung involvement compared to female patients.