Comparative Cost-Effectiveness of Bile Acid Sequestering Resins, HMG Co-A Reductase Inhibitors, and Their Combination in Patients with Hypercholesterolemia

Abstract

OBJECTIVE: To determine the cost-effectiveness of bile acid sequestrants (resins) alone, HMG Co-A reductase inhibitors alone, and a combination of a resin with an HMG Co-A reductase inhibitor in patients with hypercholesterolemia. DESIGN: Retrospective, open-label, cost-effectiveness analysis. SETTING: University-based outpatient lipid clinic. PARTICIPANTS: Patients managed in our lipid clinic with an LDL-cholesterol (LDL-C) greater than 160 mg/dL following eight weeks on an American Heart Association Step I diet were eligible for this study. INTERVENTIONS: Patients were treated with bile acid sequestrants alone, an HMG Co-A reductase inhibitor alone, or a combination of both drugs to achieve an LDL-C of less than 130 mg/dL. Costs included in the analysis were initial and concomitant drug acquisition (Redbook average wholesale price), safety and efficacy monitoring tests (liver function, creative phosphokinase, eye examinations, lipid profiles), clinic visits ($28/visit), managing side effects. Patients were followed for one year after initiation of lipid-lowering therapy. Cost-effectiveness was calculated as dollars spent per year per mg/dL reduction in LDL-C. MEASUREMENTS: Percent reduction of LDL cholesterol, total cost of treatment, and cost per mg/dL reduction in LDL cholesterol. RESULTS: A total of 141 patients were included in the analysis: 42 patients on resins alone, 56 patients on HMG inhibitors alone, and 43 on a combination resin-HMG inhibitor. Total yearly per patient costs for treatment was $1,532 for resins, $1,635 for HMG inhibitors, and $2,556 for combination therapy. Cost per patient per year per mg/dL LDL-C reduction was $49 for resins alone, combination therapy. Low-dose resin therapy $25 for HMG inhibitors alone, and $30 for was more cost-effective than high-dose resin therapy in patients treated with either monotherapy ($20 versus $57) or combination therapy ($26 versus $33). CONCLUSION: The selection of lipid-lowering therapy should be determined by the magnitude of LDL-C reduction required and the cost effectiveness of therapy. HMG inhibitors alone and bile acid sequestrant-HMG inhibitor combinations are the most cost-effective. When combination regimens are used, low-dose resin therapy is preferable.