Delay and Pay? Healthcare Costs Associated with Late Oral Anti-coagulant Prescribing in People with Atrial Fibrillation

Background Atrial fibrillation (AF) is associated with increased morbidity and mortality and exerts an increasingly significant burden on global healthcare resources, with its prevalence rising with an ageing population. Despite a substantial thromboembolic risk, particularly in the period immediately following diagnosis, oral anti-coagulation is frequently not initiated or is delayed. The aim of this study was to evaluate healthcare costs in people with AF, comparing those who were commenced on oral anti-coagulation in the immediate period following the index diagnosis date with those in whom initiation was late and those who never started anti-coagulation. Methods This retrospective cost analysis used linked Scottish health data to identify adults newly diagnosed with AF between January 1st 2012 and April 30th 2019 with a baseline CHA2DS2-VASc score of ≥ 2. This AF population was sub-divided according to timing of the first prescription of oral anti-coagulant (OAC) during a 2-year follow-up period: never started (OAC never initiated), immediate OAC (OAC prescribed within 60 days of incident AF diagnosis), and delayed OAC (OAC prescribed more than 60 days after incident AF diagnosis). A two-part model was developed, adjusted for key covariates, including age, sex, and frailty, to estimate costs for inpatient admissions, outpatient care, prescriptions, and care home admissions, and overall costs. Results Of an overall AF population of 54,385, 26,805 (49.3%) never commenced OAC, 7654 (14.1%) initiated an OAC late, and 19,926 (36.6%) were prescribed anti-coagulation immediately. The mean adjusted cost for the overall AF population was £7807 per person per year (unadjusted: £8491). Delayed OAC initiation was associated with the greatest adjusted estimated mean annual cost (unadjusted: £13,983; adjusted: £9763), compared to those that never started (unadjusted: £10,433; adjusted: £7981) and those that received an immediate OAC prescription (unadjusted: £3976; adjusted: £6621). Increasing frailty, mortality, and female sex were associated with greater healthcare costs. Conclusion AF is associated with significant healthcare resource utilisation and costs, particularly in the context of delayed or non-initiation of anti-coagulation. Indeed, there exists substantial opportunity to improve the utilisation and prompt initiation in people newly diagnosed with AF in Scotland. Interventions to mitigate against the growing economic burden of AF should focus on reducing admissions to hospitals and care homes, which are the principal drivers of costs; prescriptions and outpatient appointments account for a relatively small proportion of overall costs for AF.