Compliance patterns of patients treated with 2 separate antihypertensive agents versus fixed-dose combination therapy

Given the complexity of treating hypertension and achieving blood pressure control, compliance is extremely important to improve patient outcomes. Recognizing the detrimental effects of uncontrolled hypertension, the goal of our study was to assess the compliance patterns of patients treated with a combination of an ACE inhibitor plus dihydropyridine calcium channel blocker (ACEI + DHP-CCB) as two separate tablets versus a fixed-dose combination therapy of amlodipine besylate/benazepril HCl. A retrospective analysis of pharmacy claims from a managed care organization in the Northeast region was conducted. Patients who received at least 2 prescriptions for an ACEI + DHP-CCB (n=3,367) or amlodipine besylate/benazepril HCl (n=2,839) were identified and followed for an average of 247 days and 259 days, respectively. Compliance defined as medication possession ratio (MPR) was calculated based on daily possession of the ACEI, DHP-CCB and amlodipine besylate/benazepril HCl. The number of other medications the patient was receiving was measured counting major AHFS drug classes to estimate the impact of overall drug burden on compliance with antihypertensive therapy. Antihypertensive drug compliance with the ACEI + DHP-CCB as two separate agents and the fixed-dose combination (amlodipine besylate/benazepril HCl) were 69% and 88%, respectively. The average number of major AHFS drug classes the patients were on was 5.2 in the ACEI+DHP-CCB group and 4.0 in the amlodipine besylate/benazepril HCl group. The number of drug classes patients were receiving during the study period impacted MPR values for the study medications. As the number of concomitant drugs received by the ACEI + DHP-CCB and amlodipine besylate/benazepril HCl patients increased, the difference in MPR ratios between the 2 cohorts increased in favor of amlodipine besylate/benazepril HCl (from 12.2 percentage points to 24.6 percentage points). Compliance with amlodipine besylate/benazepril HCl was superior to ACEI+DHP-CCB regardless of number of concomitant drugs patients were receiving. Patients on amlodipine besylate/benazepril HCl (a fixed-dose combination) were more compliant than patients receiving an ACE-inhibitor and dihydropyridine calcium channel blocker as two separate agents. Better patients outcomes may be associated with this better compliance. Am J Hypertens (2004) 17, 223A–223A; doi: 10.1016/j.amjhyper.2004.03.592