Objectives: Single-pill combination therapy (amlodipine/atorvastatin) might be more effective than double-pill therapy (amlodipine+atorvastatin) in patients with diabetes and concomitant hypertension requiring statin therapy. We compared the cost-effectiveness of a single-pill with that of double-pill for control of low density lipoprotein cholesterol (LDL-C) levels, with the ultimate goal of cardiovascular disease prevention, in these patients using a cost-effectiveness analysis model that considered medication adherence.
Methods: Effectiveness was defined as the percentage (%) attainment of target LDL-C levels (<100 mg/dL) based on adherence for each therapy. Adherence was defined as compliance to medication (≥80% proportion of days covered). A systematic review of the literature was conducted to determine the proportion of patients who were adherent and target goal attainment based on adherence level. The annual medication costs were based on the adherence levels for each regimen. The average cost-effectiveness ratio (ACER) was calculated as the cost per % attainment of the target LDL-C level.
Results: The ACER for the single-pill regimen was lower than for the double-pill regimen (4,123 vs. 6,062 Korean won per 1% achievement of target goal). Compared with the double-pill, the medication costs were approximately 32% lower with the single-pill.
Conclusion: A single-pill for reductions in LDL-C is cost-effective compared with double-pill in hypertensive patients with type 2 diabetes.
Keywords: Amlodipine besylate; Atorvastatin calcium; Cost-effectiveness analysis; Low density lipoprotein cholesterol; Medication adherence.