Gender disparity in immunosuppression prescribing in progressive pulmonary fibrosis (PPF) patients from the British Thoracic Society (BTS) United Kingdom (UK) interstitial lung disease (ILD) registry

Introduction: Gender may impact outcomes in PPF.

Objectives: This study aimed to explore gender differences in patients with PPF from the BTS UK ILD registry.

Methods: We retrospectively analysed baseline clinical data and treatments of patients with PPF between February 2023 and May 2024. Female and male patient characteristics were compared. The statistic will be significant if the result is p<0.05.

Results: 106 patients with PPF were enrolled; 60 (57%) were males. The diagnosis of hypersensitivity pneumonitis was higher in females than males (15.1% vs 9.4%, p=0.03), whereas asbestosis was more common in males than females (13.2% vs 0%, p=0.00). Treatment with methotrexate (MTX) was more frequently prescribed for males (9.4% vs 1.9%, p=0.04), whilst hydroxychloroquine (HCQ) use was more prevalent in females (5.7% vs 0.9%, p=0.02). Among 12 patients with MTX, there were 58% of males had rheumatoid arthritis (RA)-ILD and 25% had sarcoidosis, whereas 17% of females had RA-ILD. Males with MTX had non-significant lower forced vital capacity percent predicted than females (73% vs 87%). Of 7 patients with HCQ, there were 43% of females with RA-ILD and non-specific interstitial pneumonia respectively, and 14% of male with RA-ILD. There was no significant difference between genders in both MTX and HCQ groups.

Conclusions: Gender differences exist in the diagnosis and treatment of patients with PPF. Despite similar presentations, lung function, and imaging findings, females were less likely to be treated with the second-line immunosuppressant MTX and more likely prescribed HCQ than their male counterparts.