ICS withdrawal and rate of FEV1 decline in a primary care COPD population in England

Abstract

<b>Introduction:</b> WISDOM reported a 43ml difference in FEV₁ in COPD patients on triple therapy (TT) (ICS/LABA/LAMA) who withdrew from ICS compared to patients remaining on TT over 1 year[1]. <b>Aim:</b> We investigated ICS withdrawal and rate of FEV₁ decline in primary care COPD patients who did not necessarily meet inclusion criteria for WISDOM. <b>Methods:</b> Current or ex-smoking COPD patients ≥35years of age with hospital (HES) linked primary care (CPRD-Aurum) records between 01/01/04-30/09/19 were included. All patients had ≥4 months of TT prescriptions at baseline. Those later prescribed LABA/LAMA only were categorised as ICS withdrawers. Index date was the first date of LABA/LAMA prescription for ICS withdrawers and the first TT prescription date after 4 months for those remaining on TT. End of follow-up was 30/09/19 or before if patients died or transferred out of practice. Patients were required to have ≥2 FEV₁ measurements ≥6 months apart to estimate rate of FEV₁ decline using mixed linear regression adjusted for baseline age, gender, smoking status, FEV₁ % predicted, BMI, stroke, exacerbation frequency, and time on baseline TT. <b>Results:</b> 60,645 COPD patients were included of whom 6,974 (11.3%) withdrew from ICS. ICS withdrawers were more likely to be ex-smokers, not have a current diagnosis of asthma, and have fewer baseline exacerbations than those remaining on TT. Adjusted mean rate of FEV₁ decline was -36.4ml/year (95% CI -33.6 to -31.5) in ICS withdrawers and -32.6ml/year (95% CI -33.6 to -31.5) in those remaining on TT (difference p=0.014). <b>Conclusion:</b> In contrast to the WISDOM trial, mean rates of FEV₁ decline were clinically similar between COPD patients on TT and COPD patients who withdrew from ICS.