SILENT LUNGS IN SILENT JOINTS: EARLY PULMONARY CLUES IN RHEUMATOID ARTHRITIS – A SYSTEMATIC REVIEW & META-ANALYSIS

Abstract

Rheumatoid arthritis (RA) is a systemic autoimmune condition that extends beyond the joints, with pulmonary involvement contributing substantially to long-term morbidity. As lung disease in RA often begins silently, pulmonary function tests (PFTs) offer a potential window to detect early physiologic changes before symptoms appear. This systematic review and meta-analysis, conducted according to PRISMA standards, synthesised evidence from studies reporting spirometric and diffusion parameters in RA. Ten eligible studies, including cross-sectional and prospective designs, were analysed, encompassing a diverse cohort of RA participants. Across studies, RA patients consistently demonstrated reduced lung function compared with controls, with significant declines in FEV1 (WMD –0.21 L; 95% CI –0.28 to –0.14) and FVC (WMD –0.19 L; 95% CI –0.26 to –0.12). Notably, these abnormalities emerged even in individuals without overt respiratory complaints, highlighting the subclinical nature of pulmonary involvement in RA. The findings support the role of PFTs as early physiologic indicators of lung disease in RA and underscore the value of incorporating baseline and serial PFT monitoring into routine care to facilitate timely detection and intervention for pulmonary complications.