RT Journal Article SR Electronic T1 Inhaled corticosteroids for COVID-19: a real-world data analysis on guideline adherence JF BJGP Open JO BJGP Open FD Royal College of General Practitioners SP BJGPO.2024.0135 DO 10.3399/BJGPO.2024.0135 VO 9 IS 2 A1 van Egeraat, Jasper WA A1 Kuijpers, Ton A1 Burgers, Jako A1 van Os, Hendrikus A1 Chavannes, Niels H A1 Bonten, Tobias N YR 2025 UL http://bjgpopen.org/content/9/2/BJGPO.2024.0135.abstract AB Background The recommendation to consider prescribing inhaled corticosteroids (ICSs) to a subgroup of vulnerable patients with COVID-19 was added to the Dutch medical guideline on 2 November 2021, and was also adopted by other countries during the pandemic.Aim To evaluate the adherence of GPs to this guideline, and whether the quality of real-world data is sufficient to study the effect of revised guidelines on prescribing behaviour.Design & setting A retrospective cohort study using Dutch primary care data from the Extramural Leiden University Medical Center (LUMC) Academic Network database, containing patient data of 129 general practices in the Leiden – The Hague area.Method We performed an interrupted time series analysis to measure the effect of the new recommendation on the prescription rate of ICSs, accounting for general trends and seasonal fluctuations.Results Between 1 July 2020 and 1 August 2022, 131 482 patients had 164 098 COVID-19 consultations. During this period, 1709 patients received 2094 ICS prescriptions for COVID-19. After the guideline update, there was an instantaneous decrease in prescription rate (incidence risk ratio [IRR] 0.47, 95% confidence intervals [CI] = 0.32 to 0.69). Prescription rate in the subgroup of vulnerable patients did not change significantly (IRR 0.93, 95% CI = 0.66 to 1.32), while less vulnerable patients were prescribed significantly fewer ICSs (IRR 0.29, 95% CI = 0.14 to 0.59).Conclusion The revision to the COVID-19 guideline had significant impact on GPs’ prescribing behaviour soon after publication: prescription rate remained constant for vulnerable patients, while less vulnerable patiens received ICS prescriptions significantly less often. Using electronic health records it is feasible to assess changes in guideline adherence using interrupted time series.