Cost-effectiveness analysis of intensive blood pressure control in Korea

Abstract

This study was a cost-effectiveness analysis of intensive blood pressure (BP) control among hypertensive patients in Korea. We constructed a Markov model comparing intensive versus standard BP control treatment and calculated the incremental cost-effectiveness ratio. The study population consisted of hypertensive patients over 50 years old with systolic blood pressures (SBPs) exceeding 140 mmHg and at high risk of cardiovascular disease. Treatment alternatives included lowering the SBP below 120 mmHg (intensive) and 140 mmHg (standard) for target BP. We assumed five scenarios with different medication adherence. The effectiveness variable was quality-adjusted life years (QALYs), and costs included medical costs related to hypertension (HT), complications, and nonmedical costs. In addition, we performed a sensitivity analysis to confirm the robustness of the results of this study. Scenario 5, with 100% medication adherence, showed the lowest incremental cost-effectiveness ratio (ICER) of $1,373 USD, followed by scenario 1 (first 15 years: 62.5%, 16-30 years: 65.2%, after 30 years: 59.5%), scenario 2 (first five years: 62.5% decrease by 5% every five years), and scenario 3 (first 10 years: 62.5% decrease by 10% every 10 years). The ICERs in all scenarios were lower than the willingness to pay (WTP) threshold of $9,492-$32,907 USD in Korea. Tornado analysis showed that the ICERs were changed greatly according to stroke incidence. Intensive treatment of HT prevents cardiovascular disease (CVD); therefore, intensive treatment is more cost-effective than standard treatment despite the consumption of more health resources. ICERs are considerably changed according to medication adherence, confirming the importance of patient adherence to treatment.

Keywords: Cardiovascular disease; Cost-effectiveness analysis; Hypertension; Intensive blood pressure control.