PS-P07-8: TREATMENT STRATEGIES AND ADHERENCE TO THE TRIPLE COMBINATION OF AN ANGIOTENSIN-CONVERTING ENZYME INHIBITOR, A CALCIUM-CHANNEL BLOCKER, AND A DIURETIC

Abstract

Objective: To compare adherence to antihypertensive treatment between patients prescribed the perindopril/amlodipine/indapamide single pill combination (SPC) vs the two pill combination of an angiotensin converting enzyme inhibitor (ACEI), a calcium channel blocker (CCB), and a diuretic (D). Design and method: Using the healthcare utilization database of the Lombardy Region (Italy), patients, aged 40 years or older, who received a prescription of perindopril/amlodipine/indapamide SPC during 2015 2018 were identified and the date of the first prescription was defined as the index date. For each patient prescribed the SPC, a subject who started ACEI/CCB/D treatment as a two drug SPC plus a third drug separately (i.e. 2 pills) at the index date was identified. Adherence to the triple combination was assessed over the year after the index date as the proportion of this year period in which prescription made the triple combination available, i.e. by the proportion of the follow up days covered (PDC) by prescription. The primary aim was to compare the odds of being highly adherent to the drug therapy (PDC> 75%) between groups. A secondary aim was to compare the odds of being poorly adherent (PDC < 25%). Log binomial regression models were fitted to estimate the risk ratio, and its 95% confidence interval, of treatment adherence in relation to the drug treatment strategy, using the two pill combination as reference. Adjustments were made for several demographic and clinical covariates. Results: 28,210 patients prescribed the perindopril/amlodipine/indapamide SPC were identified and matched to 28,210 patients prescribed ACEI/CCB/D in two pills. Compared with patients on the two pill combination, those treated with a SPC were slightly younger (68 vs 71 years) and more frequently men (54% vs 48%) with no between group difference in the clinical profile. About 59% and 25% of patients prescribed the three drug treatment as SPC and two pill combination showed high adherence, respectively. Compared with patients under two pill combination, those who were treated with the SPC had a higher propensity to be highly adherent to the triple combination (risk ratio: 2.38, 95% confidence interval 2.32 2.44). This was the case regardless of the sex, age, patient clinical status, and number of co treatments. The odds of being poorly adherent to treatment was much lower in the SPC than in the two pill combination group (risk ratio: 0.33, 0.31 0.34). Conclusions: In a real life setting, patients who were prescribed the perindopril/amlodipine/indapamide SPC exhibited more frequently a good adherence to antihypertensive treatment than those prescribed a two pill combination of ACEI/CCB/D.