Pharmacy-led implementation of evidence based medicine in primary care : Evaluating Diuretics in Usual Care study (EVIDENCE)

Abstract

Introduction Obtaining evidence of comparative effectiveness and safety of widely prescribed drugs in a timely cost-effective way is emerging as a major global challenge for healthcare systems. The Evaluating Drugs in Normal Care (EVIDENCE) programme addresses this challenge through novel methodology. We describe an exemplar pilot study comparing thiazide type diuretics for hypertension. Method Patients prescribed either indapamide or bendroflumethiazide for hypertension were identified in each primary care practice recruited. Random allocation of a prescribing policy for one or other of these drugs was then applied to the whole practice and where required repeat prescriptions were switched to comply with randomised policy. Patients were informed of the potential switch by letter with the option to discuss further with the study team and/or opt-out of the switch. Routinely collected hospitalization and death data in NHS will be used to compare cardiovascular event rates between the two policies. Results We found bendroflumethiazide was prescribed to 78% of patients prescribed either of these drugs despite recent NICE preference for indapamide. 29 primary care practices in 5 Scottish NHS boards were recruited and 14 randomised to indapamide and 15 to bendroflumethiazide creating a study population of 5985 patients. Less than 0.23% of patients opted out. Conclusion This pilot study demonstrated the feasibility and cost efficiency of the EVIDENCE approach. A relatively large study was generated rapidly with negligible disruption to practice workflows. EVIDENCE methodology offers a novel way to compare the effectiveness of a wide range of medicines where there is clinical equipoise.