New data on Covid-19 morbidity and mortality in people with rheumatic diseases

Priscilla Lynch provides a round-up of some of the most topical research presented at this year’s EULAR Congress, which took place virtually from 2-5 June

Population-based data from Spain presented at the 2021 EULAR Congress show individuals with rheumatoid arthritis (RA) had an increased risk of Covid-19 diagnosis and hospitalisation compared to the general population. Similarly, data from the ARTIS database in Sweden show risks of severe Covid-19 were increased among people with inflammatory joint diseases.

Arani Vivekanantham and colleagues investigated the association between RA and the risk of Covid-19 diagnosis, hospitalisation with Covid-19, and Covid-19-related death. This population-based cohort study includes all individuals registered in the Information System for Research in Primary Care (SIDIAP) – which covers over 80 per cent of the population of Catalonia, Spain. This information was linked to region-wide SARS-CoV-2 testing, hospital and mortality records. Outpatient diagnoses of Covid-19, hospitalisations and deaths with Covid-19 were identified between 1 March and 6 May 2020.

A total of 5,586,565 people were identified, of which 16,344 had RA. Having RA was positively associated with being diagnosed with Covid-19, and being hospitalised with Covid-19. However, the authors did not find an association between RA and the risk of worsening from outpatient diagnosis to hospitalisation or death, or from hospitalisation to death.

The authors believe this is the largest study performed to date looking at Covid-19 outcomes in people with RA. Further research is needed to address factors linking RA and Covid-19 outcomes, including the presence of other comorbidities, underlying RA disease activity, and the use of immunosuppressive medications. A second poster from Bower and colleagues looked at all-cause mortality, absolute and relative risks for severe Covid-19 in people with chronic inflammatory joint diseases and compared both over time and to the general population.

Using data from ARTIS – a Swedish national database – data on hospitalisations, admission to intensive care, and deaths due to Covid-19 were analysed in 110,567 people with inflammatory joint disease, including RA, psoriatic arthritis, ankylosing spondylitis, spondyloarthritis, or juvenile idiopathic arthritis. These were compared to outcomes for 484,277 people in the general population.

In all groups, the absolute risk of death from any cause in 2020 was higher than 2015-2019, with a peak in mid-April, but the relative risks of death versus the general population remained similar. Among people with inflammatory joint disease in 2020, the risk of hospitalisation, admission to intensive care, and death due to Covid-19 was 0.5 per cent, 0.04 per cent and 0.1 per cent, respectively.

Following the original abstract submission, Dr Bower added an update that among people with inflammatory joint disease in 2020, the risk of hospitalisation, admission to intensive care, and death due to Covid-19 was 0.3 per cent, 0.03 per cent and 0.07 per cent, respectively.