Sequential drug decision problems in long-term medical conditions: a case Study of Primary Hypertension Eunju Kim ba, ma, msc

4.3.1Comparison of cost-effectiveness results

Eight cost-minimisation analyses (CMAs), eight CEAs and three cost-utility analyses (CUAs) were identified. A summary table of the included studies is provided in Appendix 5. Where insignificant differences in blood pressure lowering effect or prevention of CVDs across antihypertensive drugs was assumed, CMAs consistently showed that Ds-based treatments were the least expensive regimen^[249-256]. The greater part of the difference in costs was attributed by drug acquisition costs. The differences in other cost components such as the costs for physician visit and laboratory test could not offset the difference in drug acquisition costs because newer drugs such as CCBs and ACEIs were more expensive than Ds by a factor between 4^[250] and 73^[251]. Although some studies included the costs for treating AEs, the impact on total costs was imperceptible where equal effectiveness across antihypertensive drugs was assumed^{[249, 256]}. This result was robust in a range of sensitivity analyses with varying assumptions of efficacy of ACEIs, utility values and costs associated with potassium supplementation, laboratory tests, clinical visits, compliance and side effects.

In most CEA or CUA studies, Ds or BBs-based regimens also showed greater cost-effectiveness compared with ACEIs or ARBs. However, there were some differences in the rank of cost-effectiveness depending on patient subgroup. For example, Ds were the most cost-effective drug for patients at high risk of HF, but not for patients at a high risk of DM. CCBs were the most cost-effective drug for patients over 55 years, at low risk of HF or at high risk of DM. For patients at high levels of DM risk and intermediate levels of HF risk, ACEIs or ARBs were the most cost-effective alternative to Ds or CCBs because of the difference in relative treatment effect of drugs that act on the risk of CVDs or DM^[63]. That is, CCBs are associated with lower rates of stroke and MI, but higher rates of HF, whereas ACEIs or ARBs are associated with lower rates of HF and DM but higher rates of stroke^[63].