[Characteristics of patients with systemic sclerosis who develop interstitial lung disease].

Background: Systemic sclerosis associated-interstitial lung disease (SSc-ILD) show a high mortality. The factors associated SSc-ILD have shown variability in different populations. There are few studies in Mexican mestizos. Objective: To analyze the epidemiological, clinical and paraclinical factors associated with SSc-ILD. Material and methods: Cross-sectional study, where patients > 18 years of age with a diagnosis of SSc according to EULAR/ACR 2013 criteria and diagnosis of ILD by forced vital capacity (FVC) < 70% and > 5% of affected lung area on tomography were included. The strength of association of the factors for ILD was measured by odds ratio (OR) with 95% confidence intervals (95% CI). The significant variables were analyzed by multiple logistic regression with adjustment. Results: Of the 80 patients with SSc, 38 (47.5%) had ILD. Risk factors such as smoking, higher activity index, lower FVC, anti-topoisomerase I antibodies, and protective factors such as a limited SSc, early capillaroscopic pattern, and anti-centromere antibodies (ACA) were associated with ILD. In the multivariate analysis, a higher activity index with OR 4.17, (95% CI 2.01-8.65) persisted as a risk factor, while ACA with OR 0.17, (95% CI 0.03-0.85) persisted as a protective factor associated with SSc-ILD. Conclusions: A higher index of activity and ACA persisted as factors associated with SSc-ILD.