The association of angiotensin receptor blocker-based combination therapy with persistence and adherence in newly treated, uncomplicated hypertensive patients

Purpose: We compared treatment adherence and persistence during treatment with an angiotensin receptor blocker (ARB)-based single pill combination (SPC) and free equivalent combination (FEC) and between SPCs of an ARB with a thiazide diuretic (TD) and an ARB with a calcium channel blocker (CCB) as initial treatment in uncomplicated hypertensive patients who received pre-packaged medications from the pharmacy.

Patients and methods: Uncomplicated hypertensive patients who started combination treatment consisting of ARB and either TD or CCB were identified from a Korean national claims database. We used propensity score matching to construct two pairs of cohorts: SPC and FEC cohorts (20,175 patients per cohort) and SPC cohorts of ARB + TD and ARB + CCB (45,253 patients per cohort). We compared adherence measured via the medication possession ratio as well as overall 1-year and initial treatment persistence.

Results: Compared with the FEC cohort, the SPC cohort had significantly higher medication adherence (OR 1.31, 95% CI 1.25-1.37), overall persistence (HR 1.33, 95% CI 1.28-1.38), and initial treatment persistence (HR 1.61, 95% CI 1.56-1.64). Neither the rate of medication adherence nor the rate of treatment persistence differed significantly between the ARB + TD and ARB + CCB cohorts. However, the ARB + CCB cohort had a significantly higher rate of initial treatment persistence than did the ARB + TD cohort (HR 1.12, 95% CI 1.10-1.14).

Conclusion: Our data suggest that, compared with FEC therapy, initiating an ARB-based SPC therapy may increase adherence and persistence in patients with uncomplicated hypertension who also receive pre-packaged medication from the pharmacy. Although using an ARB + CCB SPC may improve initial treatment persistence, it does not increase adherence or overall persistence when compared with an ARB + TD SPC.