Persistence with Antihypertensive Medications in Uncomplicated Treatment-Naïve Patients: Effects of Initial Therapeutic Classes

We aimed to assess one-year persistence with antihypertensive therapy (AHT) among newly treated uncomplicated hypertensive patients in Korea and to evaluate the effect of initial therapeutic classes on persistence. We retrospectively analyzed a random sample of 20% of newly treated uncomplicated hypertensive patients (n = 45,787) in 2012 from the National Health Insurance claims database. This group was classified into six cohorts based on initial AHT class. We then measured treatment persistence, allowing a prescription gap of 60 days. Adherence to AHT was assessed with the medication possession ratio. Calcium channel blockers (CCB, 43.7%) and angiotensin receptor blockers (ARB, 40.3%) were most commonly prescribed as initial monotherapy. Overall, 62.1% and 42.0% were persistent with any AHT and initial class at one year, respectively, and 64.2% were adherent to antihypertensive treatment. Compared with ARBs, the risk of AHT discontinuation was significantly increased with initial use of thiazide diuretics (hazard ratio [HR], 3.16; 95% confidence interval [CI] 2.96-3.74) and beta blockers (HR, 1.86; CI, 1.77-1.95) and was minimally increased with CCBs (HR, 1.12; CI, 1.08-1.15). In conclusion, persistence and adherence to AHT are suboptimal, but the differences are meaningful in persistence and adherence between initial AHT classes.