(081) An Analysis Of The Impact Of The COVID-19 Pandemic Outbreak On Incident Patient Diagnoses In Primary Care In England Using An Interrupted Time Series

Publication Number: 418

Background: The Covid-19 pandemic caused disruption in diagnostic workflows in England, yet, the magnitude of consequences on new diagnoses in a primary care setting remain uncertain. This study may benefit the health care system in understanding the burden and the expected increase in diagnoses and, consequently, disease management in the coming years.

Objectives: To evaluate the impact of the Covid-19 pandemic outbreak on the rate of incident diagnoses in primary care in England.

Methods: An interrupted time series was used with data from the IQVIA Medical Research Database (IMRD), which encompasses 176 GP practices and more than 3.1 million patients and is broadly representative of the English population. The analysis assessed change in rate of new diagnoses before and after 1st April 2020, which was used as the intervention, indicating the outbreak of the Covid-19 pandemic in England. Data from 1st January 2017 - 1st May 2022 was included for all patients with age and sex recorded. Patients were followed-up from the end date of 12 months of continuous enrolment until the first of either censoring or incident diagnosis date of one of the outcomes of interest: atrial fibrillation, heart failure, hypertension, diabetes type 2, obesity, COPD, asthma, and rheumatoid arthritis. Poisson regression models were constructed for each outcome, with monthly total incident diagnoses as the response, and an offset to adjust for observed time-at-risk. Models included covariates for gender and time, and a harmonic covariate to adjust for seasonal fluctuations. Model results were assessed for evidence of a difference in number of diagnoses before and after the pandemic outbreak and a difference in direction of change in rate of diagnoses.

Results: The results showed that numbers of diagnoses were significantly lower after 1st April 2020 than before (RR [95% CI] for atrial fibrillation: 0.42 [0.33-0.53]; heart failure: 0.42 [0.33-0.53]; hypertension: 0.16 [0.12-0.21]; diabetes type 2: 0.21 [0.15-0.29]; obesity: 0.08 [0.06-0.13]; COPD: 0.32 [0.19-0.55]; asthma: 0.19 [0.14-0.27]; rheumatoid arthritis: 0.55 [0.33-0.91]). A significant positive change in rate of change of diagnoses after 1st April 2020 was also observed, indicating the rates are increasing over time more quickly since this time. The overall pattern observed is that crude incidence rates remained low for a couple months after 1st April 2020 before increasing to pre-Covid rates (or somewhat higher).

Conclusions: This study showed that the Covid-19 pandemic negatively impacted the incidence of new patient diagnoses during the specific period when national restrictions were first put in place in England and were at their most strict.