Background: Rheumatoid Arthritis (RA) is an immune-mediated disease with a risk of infection that doubles that of the population without RA. The risk is increased in direct relation to age, the number of previous infections and treatment with biologic disease-modifying anti-rheumatic drugs (bDMARDs), targeted synthetic disease-modifying anti-rheumatic drugs (tsDMARDs), and glucocorticoids (GCC). It is interesting to know the characteristics of SARS CoV-2 infection and its associated mortality in RA patients.

Objectives: To analyze the number of cases of SARS Cov-2 infection. To know the severity of the infection in terms of number of hospitalizations, mechanical ventilation, ICU admission, and mortality. Identify risk factors associated with infection.

Methods: Retrospective case series of a cohort of RA patients treated with bDMARDs or tsDMARDs. Patients with RA (ACR/ EULAR 2010) treated with bDMARDs or tsDMARDs from December 2019 to January 15, 2022, attended at the Rheumatology Service of the Virgen University Hospital, were reviewed. Variables related to RA and infection were collected.

Results: Data were analyzed from 565 patients, aged 59.9 ± 12.8 years; 454 (80%) women, 465 (82%) with RF and/or ACPA positive, with a RA of 14.1 ± 10.7 years. We found 64 (11.3%) cases of Sars CoV-2 infection; of these, 6 (1.6%) required admission for 6.6 ± 3.8 days and none were admitted to the ICU. Two (22%) were treated with noninvasive ventilation and none with mechanical ventilation. The immunosuppressive treatment received in the 6 months prior to SARS CoV-2 infection consisted of prednisone in 22 (34.3%) cases at doses of 4.8 ± 1.7 mg/day; MTX in 23 (35.9%) at doses of 14.7 ± 5.7mg/week; Anti-TNF drugs in 23 (39%); Anti IL-6 in 17 (26%); JAK inhibitors in 14 (22%); RTX in 5 (8%) and abatacept in 3 (5%) patients. In 32 (50%) of these, no previous vaccination against the virus was reported. Of those vaccinated, one patient (3%) had 1 dose; 8 (25%) 2 doses and 23 (71%) patients 3 doses. There were 13 (2.3%) deaths of the total cohort; of which 1 case (0.18%) died from SARS CoV-2 infection. This case was an 80-year-old woman; she had RA for 60 years, with ILD and multiple extra-articular manifestations and associated comorbidity. She was treated with prednisone (7.5 mg/day plus baricitinib (2 mg/day). Patients with SARS CoV-2 infection were younger (57.3 ± 11.7 vs 60.3 ± 12.9 years, p<0.05) and had a lower vaccination rate (50% vs 93%, p<0.0001). There was no association with the type of RA, the presence of extra-articular manifestations (including EPID) or the number, presence, or type of comorbidities. Regarding treatments, a risk association was found between previous exposure to GCC and JAK inhibitor. A protective association was found with Anti-TNF exposure.

Conclusion: The frequency of SARS CoV-2 infection in RA patients treated with bDMARDs and tsDMARDs was like that of the general population. The infection was mild to moderate, with no increase in hospitalizations, need for assisted ventilation or number of ICU admissions with respect to what was reported in the literature. Mortality was low. The absence of vaccination was found as a risk factor. Although an association was found between infection and exposure to prednisone and JAK inhibitors and Anti-TNF protector, these associations will have to be confirmed in prospective studies.

REFERENCES: NIL.

Acknowledgements: NIL.

Disclosure of Interests: Gonzalo Jurado Quijano: None declared, Ana Fernández Reboul Fernández: None declared, Jorge Luis Rodas Flores: None declared, Inés María Fernández-Maeztu Palacín: None declared, José Javier Pérez Venegas: None declared, Blanca Hernández-Cruz Lilly, Amgen, BMD, Stada, Gebro, Sandoz, Sanofi, Lilly, Gebro, Sanofi.