Persistence with antihypertensives in uncomplicated treatment-naïve very elderly patients: a nationwide population-based study

BACKGROUND: Limited studies have evaluated the medication-taking behavior in very elderly hypertensive patients. The aim of this study was to evaluate the persistence and adherence with antihypertensive agents in treatment-naïve patients, along with other related factors, according to age. METHODS: Adult (19–64 years), elderly (65–79 years), and very elderly (≥80 years) uncomplicated hypertensive patients starting antihypertensive monotherapy were identified from the National Health Insurance claims database. The first-year treatment persistence and adherence rates measured using the medication possession ratio were assessed and compared in these three age cohorts. RESULTS: After propensity score matching, three age cohorts with 6689 patients each were assembled from 228,925 uncomplicated hypertensive patients who began antihypertensive monotherapy in 2012. The treatment persistence and adherence rates over the first year were the lowest in the very elderly (59.5% and 62.8%, respectively) and highest in the elderly (65.2% and 67.9%, respectively) patients among the three age cohorts (p < 0.001). The adjusted risk for treatment non-persistence was significantly higher in the very elderly (adjusted hazard ratio, 1.20; 95% confidence interval, 1.13–1.27) compared with the elderly. Having more comorbidities, being a beneficiary of medical aid, and having a diagnosis of dementia were unique positive predictors for treatment persistence in the very elderly, along with common predictors such as female sex, dyslipidemia, and an initially chosen antihypertensive therapeutic class other than beta blockers and thiazide diuretics. CONCLUSIONS: Very elderly patients were less likely to continue antihypertensive therapy over the first year compared with their younger counterparts. Our findings suggest that a low comorbidity index and lack of medical aid support negatively affect the treatment persistence in this population.