Incidence and prevalence of Takayasu arteritis in England before and after the COVID-19 pandemic–results from RECORDER

Objectives Takayasu arteritis (TAK) is a rare large vessel vasculitis associated with substantial morbidity and mortality. Evidence on its epidemiology, including the COVID-19 pandemic’s impacts, is incomplete. We aimed to describe incidence and prevalence of TAK in England using national routinely collected healthcare data. Methods Using Hospital Episode Statistics for the whole of England (Admitted Patient Care and Outpatients), we identified all people with the ICD-10 code for TAK. We validated our case ascertainment and diagnosis date refinement strategies in five NHS Trusts and using the unique Imperial College TAK cohort of 123 confirmed cases. We calculated incidence of TAK in England from 2006-2023 (cohort design), particularly focusing on the COVID-19 pandemic, and point prevalence for 1st July 2022 (cross-sectional design). Results were reported by key demographic variables. Results Incidence of TAK in England was 1.3 (95% CI 1.3-1.4) per million per year and was stable except for a 30% drop in 2020-2021 (COVID-19 pandemic). Prevalence of TAK in mid-2022 was 22.5 per million (95% CI 21.3-23.8). Median age at diagnosis was 53 years. Incidence and prevalence were both higher in women, and in Asian/Asian British and Other ethnic groups. There was variation between different geographical areas, but socioeconomic status did not have a marked effect. Conclusion Nearly 1300 people have TAK in England, with over 70 new cases each year apart from during the COVID-19 pandemic. These estimates, based on a ten-fold larger cohort than previous European studies, will be essential in planning and commissioning pandemic-prepared specialist services.