Comorbidities in clinical cohorts of patients with idiopathic pulmonary fibrosis: a systematic review and meta-analysis

BACKGROUND: Comorbidities can influence treatment decisions and health outcomes in patients with idiopathic pulmonary fibrosis (IPF). This systematic review and meta-analysis evaluated the types and prevalence of comorbidities, as well as their impact on health outcomes, in clinical cohorts of patients with IPF. METHODS: Ovid MEDLINE and Embase were searched up to August 2024 for eligible observational studies with ≥100 adults with IPF that reported at least one comorbidity. Meta-analyses were performed for comorbidity prevalence, with associations between comorbidities and health outcomes narratively synthesised. RESULTS: A total of 251 studies (n=606 398 participants) were included. Common comorbidities were systemic hypertension (pooled prevalence 39%, 95% confidence interval (CI) 34-44%), dyslipidaemia (30%, 95% CI 20-38%), gastro-oesophageal reflux disease (27%, 95% CI 23-31%), hiatus hernia (20%, 95% CI 9-33%), overweight/obesity (22%, 95% CI 18-27%), diabetes mellitus (21%, 95% CI 19-23%), ischaemic heart disease (20%, 95% CI 17-23%) and heart failure (15%, 95% CI 13-18%). Few studies evaluated the relationships between comorbidities and health-related quality of life or IPF disease progression. Lung cancer was the only comorbidity that was consistently associated with increased short-term and long-term mortality in patients with IPF. CONCLUSIONS: A wide variety of comorbidities affect clinically encountered patients with IPF, with many having higher prevalence rates than those reported in clinical trial cohorts. This highlights the need for personalised care in the management of IPF. The relationships between different comorbidities and health outcomes warrant future studies to better inform targeted screening and management.