Pharmacoeconomic evaluation of hypothetical over-the-counter angiotensin-converting enzyme (ACE) inhibitors for the prevention of stroke in patients with grade I hypertension

The effectiveness and safety of angiotensin-converting enzyme (ACE) inhibitors for the treatment of hypertension have been confirmed during long-term use. Therefore, ACE inhibitors were selected as one candidate for the switch from ethical drugs to over-the-counter (OTC) medications. The objective of this study was to perform a cost-effectiveness analysis if ACE inhibitors were switched to OTC medications and used by grade I hypertension patients in Japan. We conducted a cost-effectiveness analysis from a social perspective over a lifetime horizon using a Markov Model in 50- year-old men and women with grade I hypertension. They were divided into 3 groups: 1) untreated group; 2) consultation group visiting a clinic and receiving prescriptions for ACE inhibitors; and 3) OTC group purchasing OTC ACE inhibitors. The cost of OTC medications was estimated based on a previous study of willingness to pay (¥7,237/month). Average life expectancies in both the OTC and consultation groups were 20.20 for men and 22.63 for women, while in the untreated group it was 19.97 for men and 22.47 for women. Incremental costs per expected life-year (ICER) were ¥1,743,557 for men and ¥8,647,069 for women in the OTC group and ¥3,819,861 for men and ¥9,639,844 for women in the consultation group. These results suggest that longer life expectancies can be achieved with ACE inhibitors, and the total cost is decreased using OTC ACE inhibitors compared with ethical drugs. OTC ACE inhibitors therefore appear be a useful alternative for patients who do not have time to visit a clinic regularly.