Quality of hypertension pharmacotherapy in Quebec: a population-based study.

ABSTRACT

BACKGROUND: Choosing the initial pharmacotherapy for new antihypertensive users and ensuring adherence to therapy can be problematic. OBJECTIVES: We sought to assess the quality of pharmacotherapy among new users of antihypertensives in Quebec, and to measure persistence with treatment in the short and longer term. METHODS: Using provincial administrative databases, a historical population-based study was conducted with a cohort of Quebec adults who filled their first antihypertensive prescription between January 1, 2007, and December 31, 2009. We described antihypertensive treatment for those with a diagnosis of hypertension (HTN) in the 5 years preceding initiation of drug therapy. Conformity with criteria for optimal use based on the 2006 Canadian Hypertension Education Program (CHEP) was evaluated. Persistence with treatment was estimated at 3 months, 1 year and 2 years after pharmacotherapy initiation. RESULTS: Among the 79,181 new antihypertensive users with HTN who started treatment between 2007 and 2009, 82.5% were first prescribed only one drug, usually an angiotensin II receptor blocker or an angiotensin-converting enzyme inhibitor and rarely a diuretic. 24.2% of newly treated hypertensive persons aged 60 or older in our sample received a beta-blocker, which is not recommended practice. The initial treatment conformed to CHEP recommendations for 72.8% of those with uncomplicated HTN. After 3 months, 69.8% of new users still persisted with their treatment. This proportion remained stable after 1 year (69.1%) and 2 years (69.2%). CONCLUSION: Conformity of antihypertensive treatment with CHEP criteria, and patient persistence with therapy, was fairly high for new users in the province of Quebec. Research is needed, however, on how to further improve pÉÉharmacotherapy quality and persistence in new users.