The additional treatment value of immunoglobulin for the treatment of rheumatoid arthritis complicated with interstitial lung disease: A propensity score‐matched pilot study

Abstract Objective To explore the additional treatment value of intravenous immunoglobulin injections for treating interstitial lung disease (ILD) caused by rheumatoid arthritis (RA). Methods This pilot study included patients with RA‐ILD. The RA‐ILD patients were grouped by treatment agents: traditional agents (disease‐modifying antirheumatic drugs, [D]MARDs] and glucocorticoids) and traditional agents plus immunoglobulin. A propensity matching score (PSM) was performed to balance the bias of baseline characteristics. The treatment efficacy and safety indicators were analyzed and compared between the two groups. Results In total, 134 patients were included in this study. After PSM, 80 patients were finally included, with 40 in each group. The immunoglobulin group consisted of 12 men and 28 women with a mean age of 51.5 ± 8.4 years (22–75 years). The control group included 13 men and 27 women, with a mean age of 50.6 ± 8.2 years (25–74 years). The chronic obstructive pulmonary disease assessment test score in the immunoglobulin group was statistically lower after treatment than in the control group (19.1 ± 3.3 vs. 17.7 ± 3.4, p = .03). The 6‐min walking distance (364.4 ± 54.3 vs. 332.3 ± 55.1, p = .04) and forced vital capacity (78.8 ± 12.6 vs. 66.6 ± 11.2, p = .05) were statistically higher in the immunoglobulin group. The high‐resolution computed tomography score and erythrocyte sedimentation rate were both statistically lower in the immunoglobulin group (both p < .05). The adverse event rate did not differ between the two groups ( p = .61). Conclusion The additional use of immunoglobulin intravenous injection is effective for the treatment of RA‐ILD with no additional adverse effects.