King's College London

Using anonymised NHS data from more than 23 million adults in England, researchers from King’s College London analysed diagnosis rates for 10 autoimmune rheumatic diseases between 2016 and 2025. While diagnosis rates recovered for some conditions following the disruption caused by the pandemic, significant gaps remain for diseases including psoriatic arthritis, rheumatoid arthritis and giant cell arteritis.

The findings, published in The Lancet Rheumatology, provide the first large population-level assessment of how diagnosis rates for autoimmune rheumatic diseases have changed since the pandemic.

The study used data from OpenSAFELY, a secure data analytics platform that provides access to anonymised NHS primary care and hospital records covering a large proportion of the population of England. The research through OpenSAFELY was conducted in collaboration with colleagues at the University of Oxford.

Across almost all of the conditions studied, there was a sudden drop in diagnoses during the first year of the pandemic. The researchers believe this is unlikely to mean fewer people developed these diseases. Instead, it could reflect the disruption to healthcare services and the challenges many people faced in accessing assessment and diagnosis at that time.

Although diagnosis rates increased later in the pandemic, there remained large deficits in diagnoses for several of the conditions as of March 2025. The largest reduction was seen in psoriatic arthritis (a type of arthritis that can occur in people with skin psoriasis), where diagnosis numbers remained around 25 per cent lower than pre-pandemic levels. Rheumatoid arthritis diagnoses were approximately 10 per cent lower than expected.

Early diagnosis is particularly important for these conditions, as effective treatments are available that can help prevent irreversible joint damage and other long-term complications. Researchers also observed a reduction in diagnoses of giant cell arteritis, a serious inflammatory condition that can lead to permanent sight loss if not treated quickly.

In contrast, diagnoses of axial spondyloarthritis (a type of arthritis that mainly affects the back in younger adults) increased above pre-pandemic levels, particularly among women.

The reasons behind these changing trends are likely to be complex. Improved diagnostic pathways, changes in clinical practice and wider public health factors may all play a role.

Importantly, the methodology used in this study could support near-real-time disease surveillance by identifying emerging trends across different demographic groups and populations.

Looking ahead, the researchers hope that approaches using routinely collected NHS data could reduce the administrative burden of manual data collection, while providing more timely insights into diagnosis patterns, treatment outcomes and healthcare inequalities. They believe similar methods could support the automated monitoring of care quality across healthcare services, helping to identify where interventions are needed to improve patient outcomes and reduce disparities in care.