Heart and Stroke Foundation of Ontario (HSFO) high blood pressure strategy's hypertension management initiative study protocol

Achieving control of hypertension prevents target organ damage at both the micro and macrovascular level and is a highly cost effective means of lowering the risk for heart attack and stroke particularly in people with diabetes. Clinical trials demonstrate that blood pressure control can be achieved in a large proportion of people. Translating this knowledge into widespread practice is the focus of the Hypertension Management Initiative, which began in 2004 with the goal of improving the management of this chronic health condition by primary care providers and patients in the community.

This study will test the effect of a systems change on the management of high blood pressure in real world practice in primary care in Ontario, Canada. The systems change intervention involves an interprofessional educational program bringing together physicians, nurses and pharmacists with tools for both providers and patients to facilitate blood pressure management. Each of two waves of subjects were enrolled over a 6 month period with the initial enrollment between waves separated by 9 months. Blood pressure will be measured with the BpTru ^® automated blood pressure device. To determine the effectiveness of the intervention, a before and after analysis within all subjects will compare blood pressure at baseline to annual measurements for the three year study. To assess whether the intervention has an impact on blood pressure control independent of community trends, a betwen group comparison of baseline blood pressures in the delayed wave will be made with the immediate wave during the same time period, so that the immediate wave has experienced the intervention for at least 9 months. The total enrollment goal is 5,000 subjects. The practice locations include 10 Family Health Teams (FHTs) and 1 Community Health Centre (CHC) and approximately 49 primary care physicians, 15 nurse practitioners, 37 registered nurses and over 150 community pharmacists across the 11 communities throughout the province of Ontario. The 11 primary care sites will be divided into immediate and delayed groups based on geography and the use of an electronic versus a traditional chart patient record.

Initial consideration was given to randomizing the groups, however, for a number of reasons, this was deemed to not be possible. In order to ensure that the sites in the immediate intervention and delayed intervention groups are not different from each other, the sites will be assigned to the intervention groups manually to ensure a distribution of the variables as evenly as possible.

Given that HSFO approached this particular group of health care providers to participate in a program relating to hypertension, this may have heightened their awareness of the issue and affected their management of patients with hypertension. Thus, data will be collected to allow an assessment of previous practice patterns and determine any impact of the Hawthorne Effect.

Clinicaltrials.gov NCT00425828