“Together with reports of other cohorts exposed to immunosuppressant medication, these data could inform future public health guidance for individuals with autoimmune disease,” the researchers wrote.
The study, “Risk factors for severe outcomes in patients with systemic vasculitis & COVID‐19: a bi‐national registry‐based cohort study,” was published in the journal Arthritis & Rheumatology.
Systemic vasculitis is a group of disorders in which inflammation of the blood vessels causes tissue damage. The conditions are typically managed with immunosuppressants and high-dose glucocorticoids that dampen the activity of the immune system.
Since these medications also put patients at greater risk for infections, patients with systemic vasculitis are potentially more likely to have COVID-19 and to experience more severe outcomes. Yet, reports about the use of glucocorticoids in COVID-19 patients have shown inconsistent results.
A team of researchers in the U.K. and Ireland now set out to establish the factors that increase the risk for severe COVID-19 outcomes in a group of systemic vasculitis patients. Severe outcomes were defined as invasive ventilation, the need for advanced oxygen therapy, or death.
A total of 65 patients with systemic vasculitis and a diagnosis of COVID-19 were recruited at centers in the U.K. and Ireland from March to July. The most common vasculitis was AAV, about half had active disease, and patients’ median age was 70.
At the time of their COVID-19 diagnosis, about 69% of patients were receiving glucocorticoids, at a median dose of 7.5 mg of prednisone per day. Also, 22 patients had received rituximab and 10 had taken cyclophosphamide recently.
A large majority of patients (91%) were hospitalized due to COVID-19 and 11% were admitted to an intensive care unit. A total of 25 patients (38%) had severe COVID-19 outcomes, including 18 patients (23%) who died. Only one patient experienced worsening vasculitis following COVID-19 infection.
Statistical analyses then found that patients with respiratory disease were 7.5 times more likely to experience poor COVID-19 outcomes, while those using glucocorticoids had 3.7 times greater changes of severe outcomes.
The exact AAV diagnosis, disease activity, and the use of immunosuppressants other than glucocorticoids, however, did not affect the risk of severe COVID-19 outcomes. Similar results were obtained when only AAV patients were examined.
“Future work should seek to establish risk factors for severe disease in a wider population. Comparisons with controls who did not contract COVID-19 would allow assessment of incidence and risk factors for contracting COVID-19,” the investigators wrote.
Among the study’s limitations are the overrepresentation of patients with severe disease and small-vessel vasculitis, and the potential for biased selection of patients who were more vulnerable to COVID-19 due to immunosuppressive treatments and exposure at healthcare facilities.