Differences in disease characteristics and outcomes as determined by biological sex in a large UK IPF population: Analysis from the British Thoracic Society, Interstitial Lung Disease (BTS-ILD) registry data

Mulholland, Sarah; Dixon, Giles; Wells, Matthew; White, Paul; Harding, Samantha; Russell, Anne-Marie; Barratt, Shaney

Abstract

Abstract
Introduction
Growing evidence suggests that biological sex influences the incidence, presentation, diagnosis and outcomes of many lung diseases. Understanding these differences is the first step towards precision medicine to improve patient care.

Methods
In this cross-sectional study IPF patients enrolled in a national, multicentre registry (UK BTS-ILD) were categorised by sex and analysed for differences in demographics, pulmonary function tests, HRCT radiological pattern, eligibility/uptake of antifibrotics and survival.

Results
Of 7177 cases, 77.8% (n=5587) were male, median age 75 years (IQR 69.5-80.5) for both sexes (p=0.83). Males were more likely to have a history of smoking (p<0.001) and lower baseline median FVC % predicted (males 76.4%, IQR 66.2-86.7 vs females 78.8%, IQR 68.6-89.1, p<0.001). Diabetes, cardiovascular disease and gastro-oesophageal reflux disease were statistically more common in males (p<0.001), whilst major depressive illness was more common in females (p<0.001). Significantly more females experienced symptoms for >24 months prior to first clinic appointment (females 40.1% vs males 36.6%, p=0.028). Whilst more males in the cohort met eligibility criteria for antifibrotics at baseline (p<0.001), a larger proportion chose not to commence antifibrotic treatment (males 47.0% vs females 29.6%, p<0.001). Female sex was associated with longer mean survival (female 9.99 years (95% CI 9.18-10.79) vs males 8.57 years (95% CI 8.15–8.99), p<0.001). Male sex, higher age, lower baseline FVC % predicted and co-existent lung cancer were all independently associated with worse survival (p<0.001).

Conclusion
This is the first UK study to use national registry data to systematically evaluate IPF disease characteristics stratifying by biological sex and highlights distinct characteristics between groups. Future clinical trials should explicitly explore sex-specific targeted interventions and analyses, to optimise future IPF patient care.

• Journal Article Type: Article
• Acceptance Date: Aug 4, 2025
• Deposit Date: Aug 4, 2025
• Electronic ISSN: 2052-4439
• Publisher: BMJ Publishing Group
• Peer Reviewed: Peer Reviewed
• Public URL: https://uwe-repository.worktribe.com/output/14795225
• Publisher URL: https://bmjopenrespres.bmj.com/