FACTORS ASSOCIATED with SEVERE COVID-19 OUTCOMES in PATIENTS with IDIOPATHIC INFLAMMATORY MYOPATHY: RESULTS from the COVID-19 GLOBAL RHEUMATOLOGY ALLIANCE PHYSICIAN-REPORTED REGISTRY

ABSTRACT

Background: There is a paucity of data in the literature about the outcome of patients with idiopathic infammatory myopathy (IIM) who have been infected with SARS-CoV-2. Objectives: To investigate factors associated with severe COVID-19 outcomes in patients with IIM. Methods: Data on demographics, number of comorbidities, region, COVID-19 time period, physician-reported disease activity, anti-rheumatic medication exposure at the clinical onset of COVID-19, and COVID-19 outcomes of IIM patients were obtained from the voluntary COVID-19 Global Rheumatology Alliance physician-reported registry of adults with rheumatic disease (from 17 March 2020 to 27 August 2021). An ordinal COVID-19 severity scale was used as primary outcome of interest, with each outcome category being mutually exclusive from the othera) no hospital-ization, b) hospitalization (and no death), or c) death. Odds ratios (OR) were estimated using multivariable ordinal logistic regression. In ordinal logistic regression, the effect size of a categorical predictor can be interpreted as the odds of being one level higher on the ordinal COVID-19 severity scale than the reference category. Results: Complete hospitalization and death outcome data was available in 348 IIM cases. Mean age was 53 years, and 223 (64.1%) were female. Overall, 167/348 (48.0%) people were not hospitalized, 136/348 (39.1%) were hospitalized (and did not die), and 45/348 (12.9%) died. Older age (OR=1.59 per decade of life, 95%CI 1.32-1.93), male sex (OR=1.63, 95%CI 1.004-2.64;versus female), high disease activity (OR=4.05, 95%CI 1.29-12.76;versus remission), presence of two or more comorbidities (OR=2.39, 95%CI 1.22-4.68;versus none), predni-solone-equivalent dose >7.5 mg/day (OR=2.37, 95%CI 1.27-4.44;versus no gluco-corticoid intake), and exposure to rituximab (OR=2.60, 95%CI 1.23-5.47;versus csDMARDs only) were associated with worse COVID-19 outcomes (Table 1). Conclusion: These are the frst global registry data on the impact of COVID-19 on IIM patients. Older age, male gender, higher comorbidity burden, higher disease activity, higher glucocorticoid intake and rituximab exposure were associated with worse outcomes. These fndings will inform risk stratifcation and management decisions for IIM patients.