AN ECONOMIC ANALYSIS OF HEART AND STROKE FOUNDATION OF ONTARIO'S HYPERTENSION MANAGEMENT INITIATIVE (HMI)

Background: Hypertension is a major risk factor for cardiovascular disease (CVD), and continues to be sub-optimally treated.  The Heart and Stroke Foundation of Ontario’s Hypertension Management Initiative (HMI) is a multi-disciplinary primary care delivery model designed to address this need.

Purpose : To perform an economic evaluation of the HMI program.

Method:  Our cost-effectiveness analysis was done from the perspective of the Ministry of Health and Long Term Care of Ontario.  The time-horizon was the patient’s life-time, and all health outcomes and costs were discounted at 5% per annum.  Costs were adjusted to 2010 Canadian dollars.  Primary outcome was the incremental cost-effectiveness ratio (ICER). We created a matched group of patients with risk factor profiles at baseline (standard care cohort) and after the HMI intervention (HMI cohort). The risk of CVD and life-expectancy for each patient at these 2 time points was estimated using the Framingham risk equation and corresponding life-tables. The risk of ESRD was also estimated using estimates from the literature.  Costs for the HMI intervention were determined by micro-costing, while a bottom-up approach was used for long term health related costs, via linkage with administrative databases.

Result: The HMI intervention resulted in a statistically significant reduction in systolic blood pressure, from 134 mmHg in the standard care group to 126 mmHg in the HMI intervention group (p value <0.001).  There was a statistically significant reduction in total cholesterol (4.26 mmol/L to 3.95 mmol/L). These improvements led to an 11% relative reduction in the risk of CVD over 10 years (9.5% risk in HMI vs. 10.7% in standard care; p-value <0.001), and an 18% reduction in the risk of ESRD.  These translated into a statistically significant improvement in life-expectancy (19.78 years in HMI vs. 19.71 in standard care). The HMI intervention resulted in a reduction in hospitalizations, diagnostic tests and physician services related to CVD and ESRD, saving roughly $430 per patient over their life-time.  Incorporating all costs, the HMI cohort was estimated to have a discounted mean life-time cost of $22,929 vs. $22,793 for standard care, with an ICER of $6,769 per life-year gain.

Conclusion: HMI is a cost-effective means of providing primary care to patients with hypertension.