Cost Effectiveness of ACEIs/ARBs versus Amlodipine Monotherapies: A Single-Center Retrospective Chart Review

Abstract

The aim of this retrospective chart review study was to examine the cost effectiveness of angiotensin-converting enzyme inhibitors (ACEIs); angiotensin receptor blockers (ARBs); and dihydropyridine calcium channel blockers (CCBs) such as amlodipine, monotherapies in the management of essential hypertension among adult patients (≥18 years) without cancer, cardiovascular disease, and chronic kidney disease in the primary care clinics of a university-affiliated tertiary care hospital. Patients were followed up for at least 12 months from the initiation of therapy. Propensity score bin bootstrapping with 10,000 replications was conducted to generate the 95% confidence intervals (CI) for both treatment outcome (e.g., reduction of the systolic (SBP) and diastolic blood pressures (DBP) in mmHG) and the cost (e.g., costs of drugs, clinic visits, and labs in Saudi riyals (SAR)). Among the 153 included patients who met the inclusion criteria, 111 patients were on ACEIs/ARBs, while 44 patients were on amlodipine. On the basis of the bootstrap distribution, we found that the use of ACEIs/ARBs was associated with an incremental reduction of SBP of up to 4.46 mmHg but with an incremental cost of up to SAR 116.39 (USD 31.04), which results in an incremental cost effectiveness ratio (ICER) of SAR 26.09 (USD 6.95) per 1 mmHg reduction with 55.26% level of confidence. With regard to DBP, ACEIs/ARBs were associated with an incremental reduction of DBP of up to 5.35 mmHg and an incremental cost of up to SAR 144.96 (USD 38.66), which results in an ICER of SAR 27.09 (USD 7.23) per 1 mmHg reduction with 68.10% level of confidence. However, ACEIs/ARBs were less effective and costlier than amlodipine in reducing SBP and DBP with 44.74% and 31.89% levels of confidence, respectively. The findings of this study indicate that the use of ACEI or ARB as a monotherapy seems to be more effective than amlodipine monotherapy in the management of essential hypertension in primary care settings with minimal incremental cost.