Background Interstitial lung disease (ILD) in rheumatoid arthritis (RA) is frequent. Joint disease precedes the interstitial lung involvement by several years in most cases, although ILD may be the first RA manifestation.
Objectives The aim of this study was to evaluate the prevalence and clinical presentation of ILD in patients with early RA, and to identify factors associated with its occurrence.
Methods 48 patients (34 women and 14 men) with early RA, fulfilling 2010 ACR-EULAR classification criteria were enrolled to the study. The mean age was 59.6 years (±15.7). The mean disease duration was 4.7 months. Detailed medical and smoking history was taken. A physical examination, laboratory analysis, PFT and HRCT of the lung were performed in all patients.
Pulmonary manifestations were defined as the presence of respiratory symptoms and abnormalities revealed on physical examination of the lung.
The diagnosis of ILD was based on high resolution computed tomography (HRCT) of the lung and defined as the presence of diffuse or patchy reticular or reticulo-nodular lesions, honeycombing and/or ground-glass opacities, localized mainly in the peripheral or subpleural parts of the lower lobes.
Non-specific interstitial lung lesions were defined as the presence of parenchymal or subpleural bands, or pleural thickening.
Results Based on the definitions above, ILD was diagnosed in 11 patients (23%) and non-specific interstitial lung lesions in 20 patients (41.6%). Among patients with ILD, 6 had reticular lesions, 3 had ground-glass opacities and remaining 2 had ground-glass opacities associated with reticular lesions.
Respiratory symptoms were reported in 25 patients (52%) and included: cough (11), dyspnea (4), decreased physical endurance (3), fatigue (9) and fever (14). The physical examination revealed abnormalities in 3 patients (6.3%) and included: bilateral basal crackles (1) and wheezes and/or rhonchi (2).
Pulmonary manifestations occurred in 27 patients (56.3%). 6 of them (22%) had ILD and 11 (40.7%) non-specific interstitial lung lesions.
Among patients with ILD, 6 (54.5%) had the following pulmonary manifestations: cough (3), fatigue (2), fever (3) and bilateral basal crackles (1). 11 patients with non-specific interstitial lung lesions (55%) reported the following respiratory symptoms: cough (6), dyspnea (11), decreased physical endurance (3), fatigue (8) and fever (7).
PFT showed restrictive process in 1 patient (2.1%) with non-specific interstitial lung lesions on HRCT of the lung. The obstructive lung disease occurred in 1 patient (1.8%) with normal chest HRCT.
There were significant differences in time from the first RA symptoms to the first rheumatological assessment (9 vs 3.6 months, p- 0.008), time from the first symptoms to RA diagnosis (9.1 vs 4.6 months, p- 0.02) and time from the first symptoms to treatment (8.9 vs 4.3, p- 0.02) between patients with and without ILD.
There were no significant differences between these two groups in terms of age, gender, RA activity (ESR, CRP, SJC, TJC, DAS28, SDAI, CDAI), presence and level of RF and anti-citrulinated peptide, presence of pulmonary manifestations and results of PFT.
Conclusions Our study disclosed a great percentage of interstitial lung lesions in patients with early RA.
Delay in RA diagnosis and treatment appears to be associated with increased risk of ILD in patients with RA.
Disclosure of Interest None declared