Abstract 502: Cost-effectiveness Of Therapeutic Drug Monitoring In Patients With Resistant Hypertension

Abstract

Background: Non-adherence to anti-hypertensive medications poses a significant problem in the treatment of patients with presumed resistant hypertension (RH). Our recent study has shown that therapeutic drug monitoring (TDM) is a useful tool not only for detecting medication non-adherence but also exploring the barrier to antihypertensive drug therapy, resulting effective BP control. However, the cost effectiveness of TDM in the management of resistant hypertension has not been investigated.

Method: A Markov model was used to evaluate life-years, quality-adjusted life-years (QALYs), costs, and incremental cost-effectiveness ratios in RH patients receiving either TDM optimized therapy or standard best medical therapy (BMT). The model ran from the age of 30 to 100 years or death, using a cycle length of 1 year. Efficacy of TDM was modeled by reducing risk of hypertension-related morbidity and mortality.

Results: In the age group of 60-year olds, TDM gained 1.07 QALYs in men and 0.97 QALYs in women at additional costs of є3,854 and є3,922, respectively. Given a willingness-to-pay threshold of є35,000 per QALY gained, the probability of TDM being cost-effective compared to BMT was ≥95% in all age groups from 30 to 90 years. Incremental cost-effectiveness ratios were influenced mostly by the annual frequency of TDM testing, the rate of non-responders to TDM, and the magnitude of effect of TDM on systolic blood pressure (Figure).

Conclusion: Therapeutic drug monitoring presents a potential cost-effective health care intervention in patients diagnosed with RH. Importantly, this finding is valid for a wide range of patients, independent of gender and age.