Prevalence & Impact of COVID-19 in Systemic Sclerosis Patients and Assessment of the Demographic & Clinical Features in Cases Associated with Worse Prognosis: Results of a Single Centre Registry

Background: Our knowledge of the COVID-19 infection impact on systemic sclerosis (SSc) is scarce. This study aimed to assess the prevalence of COVID-19 infection and to determine the predictive factors of worse outcomes and death in SSc patients.

Methods: In this cohort study all patients who attended our clinic between 20^th February 2020 and 20th May 2021 were followed, and those with a history of COVID-19 infection completed the questionnaire. Results of para-clinical tests were extracted from the SSc database. The outcomes were classified as: alive vs. deceased and, mild vs. worse outcomes. Descriptive statistics and binary logistic regression models were applied.

Results: Of the total 192 SSc patients studied, COVID-19 affected 12.5%; 6% experienced mild disease, 7% were hospitalized and 3% died. The worse outcome was associated with: older age [95%CI: 1.00-1.08], smoking [95%CI: 2.632-33.094], diabetes [95%CI: 1.462-29.654], digital pitting scars (DPS) [95%CI: 1.589-21.409], diffusing capacity of the lungs for carbon monoxide [DLCO<70 [95%CI: 1.078-11.496], left ventricular ejection fraction (LVEF)<50% [95%CI: 1.080-38.651], systolic pulmonary artery pressure (sPAP)>40 mmHg [95%CI: 1.332-17.434], pericardial effusion (PE) [95%CI: 1.778-39.206], and tendon friction rub [95%CI: 1.091-9.387]. Death was associated with male gender [95%CI: 1.54-88.04], hypertension [95%CI: 1.093-2.155], digital ulcers (DU) [95%CI: 0.976-18.34], low forced vital capacity (FVC) [95%CI: 0.03-0.81], and joint flexion contracture (JFC) [95%CI: 1.226-84.402].

Conclusion: Risk factors for the worse outcome in COVID-19 infected SSc patients included, older age, smoking, diabetes, DPS, DLCO<70, LVEF<50%, sPAP>40 mmHg, PE, and TFR. Death was associated with the male gender, hypertension, DU, low FVC, and JFC.