Exploring the relationship between patient-reported outcomes and early lung involvement in rheumatoid arthritis: A prospective study

<bold>Introduction:</bold> Pulmonary manifestations are one of the most frequently observed extra-articular complications in rheumatoid arthritis (RA). <bold>Aims:</bold> To detect the connection between patient-reported outcome (PRO) and early lung involvement in RA patients. <bold>Methods:</bold> Our prospective study included a comprehensive assessment of exposure, pulmonary function tests (PFT), and the completion of patient-based questionnaires (EQ-5D-3L, Visual Analogue Scale for health (VAS) and Pittsburgh Sleep Quality Index (PSQI)) for 370 consecutive RA patients. Each patient underwent a low-dose chest CT scan. <bold>Results:</bold> RA patients (64.7 ± 10.3 years, predominantly female (80%)) were categorized into two groups based on the presence (Group 1, N=148, age 66.1 ± 9.6 years) or absence (Group 2, N=222, age 63.8 ± 10.6 years, p=0.03) of respiratory symptoms such as cough, chest pain or dyspnea. PFT and CO diffusion were significantly lower within the normal range in Group 1, including FVC% (91.5±14.7 vs. 96.4±14.7, p=0.005.), FEV1% (92.0±16.6 vs. 96.4±17.5, p=0.015), and DLCO (125.5±20.9 vs. 117.3±23.0, p < 0.001), compared to Group 2. PRO was found notably inferior in Group 1 compared to Group 2 (EQ-5D-3L index value: 0.89±0.6 vs. 0.92±0.6, p=0.002, VAS 67.2±17.5 vs. 73.9± 19.0, p=0.001, PSQI: 16.2±6.8 vs.11.3±6.18, p<0.001). RA associated lung involvement was observed on chest CT more often in Group 1 vs. Group 2. <bold>Conclusion:</bold> Respiratory symptoms, decreased quality of life and sleep are valuable indicators of early lung involvement in RA, also associated with PFT functional decline in the normal range. Pulmonary screening in RA is important especially in symptomatic patients.