COVID-19 and protection of vaccination in patients with systemic sclerosis-associated interstitial lung disease

Objectives: Data on COVID-19 in patients with interstitial lung disease are scarce and whether SARS-CoV-2 may trigger interstitial lung disease progression remains unknown. We aimed to analyze outcomes of COVID-19 in patients with systemic sclerosis-associated interstitial lung disease, including possible thoracic radiographic progression. Patients and Methods: All 43 patients with systemic sclerosis-associated interstitial lung disease followed in our center (mean +/- SD, 55.2 +/- 11.6 years, 36 female) with confirmed SARS-CoV2 infection up to 1 September 2022 were analyzed. Individual interstitial lung disease extent on high resolution CT (HRCT) performed before (up to 3 months) and after COVID-19 (2-5 months) was compared. Results: At SARS-CoV-2 infection, 9/43 patients were unvaccinated, whereas 5, 26, and 3 had received 2, 3, or 4 doses of an mRNA vaccine, respectively. Thirty-one patients were either on monotherapy with immunosuppressives (mycophenolate, n = 7; cyclophosphamide, n = 2; methotrexate, n = 10; tocilizumab, n = 7; rituximab, n = 1; etanercept, n = 1), or their combinations (n = 3). Eight patients (20%), of whom four unvaccinated, required hospitalization for pneumonia and three (7%) died of acute respiratory failure (n = 2, both unvaccinated) or cardiac arrest. Lack of vaccination was the only independent predictor for hospitalization (OR = 7.98, 95% CI: 1.25-51.09) and marginally for death (OR = 32.7, 95% CI: 0.97-1110.98), regardless of the presence of diffuse systemic sclerosis, interstitial lung disease extent greater than 20% or immunosuppressive treatment. In 22 patients with available HRCT pairs (vaccinated = 20), the interstitial lung disease extent before COVID-19 (20.4%+/- 17.8%) remained unchanged (22.4% +/- 18.5%) in all but one patient. Conclusion: SARS-CoV-2 vaccination is of outmost importance for every systemic sclerosis patient with interstitial lung disease. COVID-19 does not seem to promote progression of systemic sclerosis-associated interstitial lung disease in vaccinated patients, but further studies are warranted.