COVID Risks Raised in Rheumatoid Arthritis

Patients with rheumatoid arthritis (RA) were at increased risk for both COVID-19 and related hospitalization and death, a national VA study found.

Compared with non-RA patients and after adjustment for demographics, comorbidities, healthcare utilization, and local incidence rates, patients with RA had a 25% higher risk of COVID-19 (HR 1.25, 95% CI 1.13-1.39, P<0.05), reported Bryant R. England, MD, PhD, of the University of Nebraska Medical Center in Omaha, and colleagues.

Patients also had a 35% higher risk of COVID-19 hospitalization and death (HR 1.35, 95% CI 1.10-1.66, P<0.05), according to the study online in Arthritis & Rheumatology.

Patients with RA have an elevated risk for infections overall because of the immune dysregulation inherent in their disease, their common comorbidities, and from the immunosuppressive medications required for disease control. However, most research into infection risks among RA patients has focused on bacterial, not viral, infections.

England and co-authors noted that with the widening use of COVID-19 vaccines, priority had been given to individuals with a number of chronic conditions such as cancer, cardiovascular disease, chronic kidney disease, and diabetes, but patients with rheumatic diseases were not included in those early priority recommendations.

The team noted that although a few studies have considered rates of COVID-19 and outcomes among patients with rheumatic diseases, they were mostly limited by selection bias, heterogeneous populations, and the inclusion of a wide variety of conditions and treatments.

Therefore, to look specifically at the risks in RA, England and colleagues conducted a retrospective cohort study using Veterans Health Administration data collected from January to December 2020. Comorbidities were reported according to the Elixhauser comorbidity index, focusing on conditions that are recognized as conferring increased risks for COVID-19. Local incidence rates of COVID-19 were obtained from the data repository at Johns Hopkins University in Baltimore.

Medication use for the patient data assessed included prednisone, conventional synthetic disease-modifying anti-rheumatoid drugs (DMARDs) such as methotrexate, biologics such as tumor necrosis factor inhibitors, and targeted synthetic DMARDs such as JAK inhibitors.

The analysis included 33,886 patients with RA who were matched with the same number of non-RA patients. Those with RA were more likely to have more comorbidities, to be smokers, to have a high body mass index (BMI), and to have been hospitalized within the previous year. Recent use of DMARDs was reported for 73% of RA patients, while biologics or targeted DMARDs had been used by 34.2%.

The researchers found that during 62,894 patient-years of follow-up, there were 1,503 cases of COVID-19 among RA patients, with 388 leading to hospitalization or death (345 hospitalizations; 84 deaths). During the same follow-up period, 288 patients died of non-COVID causes.

Factors other than RA found to be significantly associated with a higher risk of COVID-19 infection (P<0.05) were:

• Black race, HR 1.22 (95% CI 1.07-1.39)
• Hispanic ethnicity, HR 1.48 (95% CI 1.23-1.78)
• Higher Elixhauser comorbidity score (per one unit), HR 1.12 (95% CI 1.09-1.15)
• Having no insurance, HR 1.40 (95% CI 1.24-1.58)
• Having a VA service-connected condition, HR 1.22 (95% CI 1.10-1.37)
• Number of hospitalizations in previous year, HR 1.11 (95% CI 1.05-1.16)
• County incidence rate per 100,000, HR 1.00 (95% CI 1.00-1.00)

In addition, having a BMI either below or above the normal range was associated with increased risk, with hazard ratios ranging from 1.36 to 1.78.

For COVID-19 hospitalization/death, increased risks (P<0.05) were observed for patients with a higher Elixhauser comorbidity score (HR 1.24, 95% CI 1.20-1.30), lack of insurance (HR 1.88, 95% CI 1.49-2.37), hospitalization in the previous year (HR 1.13, 95% CI 1.06-1.21), and county COVID-19 incidence rate (HR 1.00, 95% CI 1.00-1.00).

The investigators also undertook secondary analyses looking at the influence of medications, and found an increased risk both of COVID-19 infection (HR 1.66, 95% CI 1.36-2.03) and hospitalization/death among patients treated with DMARDs, biologics and targeted synthetic drugs, and prednisone (HR 2.12, 95% CI 1.48-3.03).

The investigators noted that the elevated risk of COVID-19 in RA patients was similar to what has been observed for patients with other chronic conditions. “Consideration should be given to establishing RA, and potentially other conditions that require treatment with similar immunosuppressive medications, as a chronic condition that receives prioritization for COVID-19 prevention and management strategies,” England and co-authors wrote.

A limitation of the study, they said, was the observational design and the possibility of unmeasured confounding.