Discontinuation of beta-blockers in cardiovascular disease: UK primary care cohort study

Aims: The present study aims to investigate patterns of beta-blocker usage in a national primary care cohort. Methods and results: This is a retrospective cohort study utilising the UK General Practice Research Database from 2004 to 2008. Inclusion criteria were (i) a first diagnosis of chronic heart failure (CHF), myocardial infarction (MI) or angina, and (ii) first-ever prescription of beta-blocker on or after 1st April 2004. Outcome measures were discontinuation of beta-blockers over time, initiation dosages, titration patterns, incidence of adverse events (AEs) and associated prescribing actions. A total of 12,493 patients (68.0% male; mean age 58.0 ± SD 17.6 years) were included. Of these, 27% had discontinued beta-blockers within 1 year of initiation, increasing to 39% by 2 years and 50% by 3 years. Persistence appeared to be greater in the MI cohort compared with angina or CHF cohorts. Beta-blocker dose at initiation averaged approximately 33% of guideline recommended target, rising to 40% in those who continued with therapy. Dyspnoea, fatigue and dizziness were the most common incident AEs at 98, 53 and 49 per 1000 patient years, with little difference between indications. Conclusion: A quarter of patients with cardiovascular disease who are commenced on a beta-blocker are no longer taking the drug by one year. This rises to 50% by three years, a finding that is consistent irrespective of whether the prescription is for prognostic (CHF or post MI) or symptomatic (angina) benefit. There is an urgent need to understand and address the prescribing difficulties of beta-blockers in these at-risk patients.