Rheumatic Flares Uncommon After COVID Vax Save

Post-vaccination disease flares were uncommon among patients with rheumatic and musculoskeletal diseases who were inoculated against COVID-19, researchers found.

Among 1,377 patients who were given two doses of a SARS-CoV-2 mRNA vaccine, 11% reported a flare of their underlying disease that required treatment, but none of the flares were severe, according to Julie J. Paik, MD, and colleagues from Johns Hopkins University in Baltimore.

And while local and systemic reactions to the vaccine were common, they were expected and did not typically interfere with normal activity, the researchers reported in Arthritis & Rheumatology.

In the clinical trials of the COVID-19 vaccines, few patients with rheumatic and musculoskeletal diseases were included, which has been cited as a reason for vaccine hesitancy in these patients, who have expressed concerns about safety after case reports of disease flares.

To address this issue, Paik's group conducted a prospective observational study of patients with rheumatic and musculoskeletal diseases who received both doses of mRNA-based COVID-19 vaccines from December 2020 to April 2021 while on immunomodulatory therapy. Participants filled out a questionnaire on local and systemic events 7 days after each dose, and a month after the second dose completed an additional questionnaire detailing their flare history before and after vaccination and associated symptoms, duration, and treatment required.

The median age of participants was 47, more than 90% were women, and 10% were nonwhite. The most common diagnosis was inflammatory arthritis (47% of participants), followed by systemic lupus erythematosus (20%); smaller numbers of patients reported vasculitis, scleroderma, and overlap connective tissue disease.

Half of patients were on combination therapy involving a biologic plus a conventional disease-modifying antirheumatic drug (DMARD) with or without corticosteroids, 26% were on a conventional DMARD, 22% were treated with a biologic alone, and the remainder received immunomodulatory or corticosteroid monotherapy.

A total of 3% of patients reported having previously had a COVID-19 infection.

In 56% of patients, a flare of the underlying disease had occurred during the 6 months before the first vaccine dose. Among the 151 patients who had a flare following vaccination, it was after the second dose in 60%. Worsening of pre-existing symptoms was reported by 91% and new-onset symptoms by 72%.

Typical flare duration was 10 days, and treatment consisted of oral corticosteroids in three-quarters of patients. None required hospitalization or intravenous therapy for the disease flare.

Factors that were associated with a flare that necessitated treatment included:

• Previous SARS-CoV-2 diagnosis, incidence rate ratio (IRR) 2.09 (95% CI 1.21-3.60)
• Flare in the 6 months before vaccination, IRR 2.36 (95% CI 1.66-3.36)
• Combination therapy, IRR 1.95 (95% CI 1.41-2.68)

In contrast, lower risk of flare was associated with conventional DMARD treatment alone (IRR 0.52, 95% CI 0.34-0.80) or biologic monotherapy (IRR 0.60, 95% CI 0.39-0.93).

Adverse reactions to the vaccine included pain at the injection site in 87% of patients after the first dose and in 86% after the second dose, as well as fatigue, reported by 60% and 80% after the first and second doses, respectively. Other systemic reactions after the second dose included headache, myalgia, and chills.

Events that were severe enough to interfere with daily activities were "reassuringly" uncommon and included myalgia in 11% and fatigue in 19%, the researchers reported. One patient was hospitalized because of diarrhea after the second dose, but none had anaphylaxis or a new diagnosis of COVID-19.

The findings of increased flare risk for patients who were on combination therapy or had a flare in the previous 6 months "may be a surrogate for more refractory disease at baseline and thus the relationship with vaccination is unclear," the researchers wrote. In addition, "there was a positive association between prior SARS-CoV-2 infection and flare, which may suggest immunological priming."

Paik and co-authors also noted that patients should be advised about common local and systemic adverse events occurring following vaccination in order to alleviate anxiety.

"These early, reassuring results may ameliorate concern among patients and inform critical discussions regarding vaccine hesitancy or refusal," the team concluded.

A potential limitation of the study, the researchers said, was the possibility of responder bias among participants.

Source Reference: Connolly C, et al "Disease flare and reactogenicity in patients with rheumatic and musculoskeletal diseases following two-dose SARS-CoV-2 messenger RNA vaccination" Arthritis Rheum 2021; doi: 10.1002/art.41924.