Prevalence and risk factors of interstitial lung disease in early systemic sclerosis and systemic sclerosis sine...

Introduction: Interstitial lung involvement (ILD) is one of the main complications in patients with systemic sclerosis (SSc), representing a significant cause of mortality. According to previous reports, ILD can appear in many patients from early stages (eSSc) to patients with established disease without skin involvement (ssSSc).

Patients were included in the ssSSc group if they met the ACR/EULAR 2013 classification criteria and had a Rodnan skin score 0. In the eSSc group, if they did not meet the former criteria but fulfilled the VEDOSS criteria. Patients must have undergone a high-resolution chest CT scan within the last six months. Experts in this complication reviewed the images, and the percentage of patients with ILD in each group was determined. A univariate and multivariate analysis was performed to determine potential risk factors for ILD, including conventional risk factors and clinical findings in both groups. Odds Ratios and their 95% confidence intervals were estimated. Statistical significance was considered when p was less than 0.05.

Data from 353 patients with SSc: 65 (18.4%) with ssSSc, and 75 (21.2%) eSSc (VEDOSS patients) were included in the study. The proportion of patients with ILD was 38% in the ssSSc group and 20% in VEDOSS patients group (p=0.03). Regarding risk factors, anticentromere antibody positivity was found to have a protective effect (OR 0.17, 95% CI 0.03-0.44, p=0.001), and anti-SCL-70 antibody presence was identified as a risk factor for ILD (OR 35.8, 95% CI 2.6-492, p=0.007). No association was found with male gender, digital ulcers, puffy fingers, or capillaroscopic findings.

ILD in patients with SSc can occur from early stages or without skin involvement. Thus, an active search for ILD is warranted, as it can be present in 1 out of 5 patients with these disease subsets.