Comparison of the first and sixth waves of the SARS-COV-2 coronavirus pandemic in patients with immune-mediated disease.

Introduction: Recent evidence shows that COVID-19 infection does not have a worse prognosis in patients with immune-mediated inflammatory diseases (IMID), although they develop a worse response to vaccination.

Objective: To compare the incidence of COVID-19 and clinical features in patients with IMID between the first and sixth waves.

Method: Prospective observational study of two cohorts of IMID patients diagnosed with COVID-19. First cohort March to May 2020, and second cohort December/2021 to February/2022. Sociodemographic and clinical variables were collected and, in the second cohort, COVID-19 vaccination status. Statistical analysis established differences in characteristics and clinical course between the two cohorts.

Results: In total, 1627 patients were followed up, of whom 77 (4.60%) contracted COVID-19 during the first wave and 184 in the sixth wave (11.3%). In the sixth wave, there were fewer hospitalisations, intensive care unit admissions, and deaths than in the first wave (p=.000) and 180 patients (97.8%) had at least one dose of vaccine.

Conclusion: Early detection and vaccination have prevented the occurrence of serious complications.