HLA-B27 did not protect against COVID-19 in patients with axial Spondyloarthritis – Data from the ReumaCov-Brasil Registry
Authors: Mota Guilherme Devidé , Marques Claudia Diniz Lopez , Ribeiro Sandra Lúcia Euzébio , de Albuquerque Cleandro Pires , Castro Glaucio Ricardo Werner , Fernandino Diana Campos , Omura Felipe , Ranzolin Aline , Resende Gustavo Gomes , Silva Nilzio Antonio da , Souza Mariana Peixoto Guimarães Ubirajara e Silva , Studart Samia , Xavier Ricardo Machado , Yazbek Michel Alexandre , Pinheiro Marcelo de Medeiros 
Published: April 2023

Abstract
Background
Some studies have suggested the HLA-B27 gene may protect against some infections, as well as it could play a benefit role on the viral clearance, including hepatitis C and HIV. However, there is lack of SARS-CoV-2 pandemic data in spondyloarthritis (SpA) patients.
Aim
To evaluate the impact of HLA-B27 gene positivity on the susceptibility and severity of COVID-19 and disease activity in axial SpA patients.
Methods
The ReumaCoV-Brasil is a multicenter, observational, prospective cohort designed to monitor immune-mediated rheumatic diseases patients during SARS-CoV-2 pandemic in Brazil. Axial SpA patients, according to the ASAS classification criteria (2009), with (cases) and without (control group) COVID-19 diagnosis, were paired to sex and age. Other immunodeficiency diseases, past organ or bone marrow transplantation, neoplasms and current chemotherapy were excluded. Demographic data, managing of COVID-19 (diagnosis, treatment, and outcomes, including hospitalization, mechanic ventilation and death), comorbidities, clinical details (disease activity and concomitant medication) were collected using the Research Electronic Data Capture (REDCap) database. Data are presented as descriptive analysis and multiple regression models, using SPSS program, version 20. P level was set as 5%.
Results
From May 24th, 2020 to Jan 24th, 2021, a total of 269 axial SpA patients were included, of whom 165 (61.3%) with COVID-19 and 104 (38.7%) without COVID-19. Most of them were men (N = 153; 56.9%) with mean age of 46.3 ± 13.8 years and long-term disease (13.1 ± 9.9 years). There were no significant statistically differences concerning social distancing, smoking, BMI, waist circumference and comorbidities. Regarding b-DMARDs, 134 (75.3%) were on TNF inhibitors and 17 (9.6%) on IL-17 antagonists. Comparing those patients with and without COVID-19, the HLA-B27 positivity was not different between groups (n = 45, 73.8% vs. n = 38, 73.1%, respectively; p = 0.93). In addition, disease activity was similar before and after the infection. On the other hand, the control group had significantly higher disease activity score, according to ASDAS-CRP (2.8 ± 1.8 vs. 1.8 ± 1.2, p = 0.03). Interestingly, no new episodes of arthritis, enthesitis or extra-musculoskeletal manifestations were reported after the COVID-19. The mean time from the first symptoms to hospitalization was 7.2 ± 3.6 days, with length of hospitalization quite similar between patients who died and those discharged (12.6 ± 7 and 13.9 ± 11.7, respectively). The global death estimation for COVID-19 was 1.9 (95%CI 0.6–4.3), regardless HLA-B27 status. No significant difference was found regarding concomitant medications, including conventional or biologic DMARDs between the groups.
Conclusions
No significant difference of COVID-19 frequency rate was observed in patients with axial SpA regarding the HLA-B27 positivity, suggesting a lack of protective effect with SARS-CoV-2 infection. In addition, the disease activity was similar before and after the infection.
Trial registration: This study was approved by the Brazilian Committee of Ethics in Human Research (CONEP), CAAE 30186820.2.1001.8807, and was registered at the Brazilian Registry of Clinical Trials – REBEC, RBR-33YTQC. All patients read and signed the informed consent form before inclusion.