Factors Associated with an Electronic Health Record-Based Definition of Post-Acute Sequelae of COVID-19 in Patients with Systemic Autoimmune Rheumatic Disease.

Many individuals with rheumatic disease are at higher risk for severe acute COVID-19. We aimed to evaluate risk factors for Post-Acute Sequelae of COVID-19 (PASC) using an electronic health record (EHR)-based definition. We identified patients with prevalent rheumatic diseases and COVID-19 at Mass General Brigham. PASC was defined by ICD codes, relevant labs, vital signs, and medications, at least 30 days following the first COVID-19 infection. Patients were followed until the earliest of incident PASC, repeat COVID-19 infection, 1 year of follow-up, death, or February 19, 2023. We used multivariable Cox regression to estimate the association of baseline characteristics with PASC risk. Among 2,459 patients (76.37% female, mean age 57.4 years), the most common incident PASC manifestations were cough (14.56%), dyspnea (12.36%), constipation (11.39%), and fatigue (10.70%). Serious manifestations including acute coronary disease (4.43%), thromboembolism (3.09%), hypoxemia (3.09%), stroke (1.75%), and myocarditis (0.12%) were rare. The Delta wave (aHR 0.63, 95% CI: 0.49-0.82) and Omicron era (aHR 0.50, 95% CI: 0.41-0.62) were associated with lower risk of PASC than the early pandemic (March 2020-June 2021). Age, obesity, comorbidity burden, race, and hospitalization for acute COVID-19 infection were associated with greater risk of PASC. Among patients with rheumatic diseases, following their first COVID-19 infection, using an EHR-based definition, we found a decreased risk of PASC over calendar time. Aside from glucocorticoids, no specific immunomodulatory medications were associated with increased risk, and risk factors were otherwise similar to those seen in the general population.