IGHG3 and interstitial lung disease: Initial univariate logistic regression analysis indicated that both IgG1 [odds ratio (OR) 2.031 (95% CI: 1.215, 3.394), P = 0.007] and IgG3 [OR 2.232 (95% CI: 1.156, 4.308), P = 0.017] were associated to an elevated risk of RP-ILD.