Impact of COVID-19 on the diagnoses, HbA1c monitoring and mortality in people with type 2 diabetes: a UK-wide cohort study involving 13 million people in primary care

Carr, M. J.; Wright, A. K.; Leelarathna, L.; Thabit, H.; Milne, N.; Kanumilli, N.; Ashcroft, D. M.; Rutter, M. K.

Background: The COVID-19 pandemic has already disproportionately impacted people with diabetes. Timely diagnosis and appropriate monitoring in people with type 2 diabetes (T2D) are necessary to reduce the risk of long-term complications. Methods: We constructed a cohort of 23M patients using electronic health records from 1709 UK general practices registered with the Clinical Practice Research Datalink (CPRD), including 13M patients followed between March and July 2020. We compared trends in diagnoses, monitoring and mortality in T2D, before and after the first COVID-19 peak, using regression models and 10-year historical data. We extrapolated the number of missed or delayed diagnoses using UK Office for National Statistics data. Findings: In England, rates of new T2D diagnoses were reduced by 70% (95% CI 68%-71%) in April 2020, with similar reductions in Northern Ireland, Scotland and Wales. Between March and July, we estimated that there were more than 45,000 missed or delayed T2D diagnoses across the UK. In April, rates of HbA1c testing in T2D were greatly reduced in England (reduction: 77% (95% CI 76%-78%)) with more marked reductions in Northern Ireland, Scotland and Wales (reduction: 84% (83-84%)). Reduced rates of diagnosing and HbA1c monitoring were particularly evident in older people, in males, and in those from deprived areas. Mortality rates in T2D in England were more than 2-fold higher (110%) in April compared to prior trends, but were only 66% higher in Northern Ireland, Scotland and Wales. Interpretation: As engagement with the NHS increases, healthcare services will need to manage the backlog and the expected increase in T2D severity due to delayed diagnoses and reduced monitoring. Older people, men, and those from deprived backgrounds with T2D may be groups to target for early intervention. Funding: National Institute for Health Research (NIHR) Greater Manchester Patient Safety Translational Research Centre