Antihypercholesterolemic effects of atorvastatin in patients previously receiving other 3-hydroxy-3-methylglutaryl coenzyme a reductase inhibitors: an open-label study

Background: Atorvastatin, a 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor, was introduced in Japan in May 2000 with purportedly potent cholesterol-lowering effects. However, only a handful of studies have assessed its efficacy and tolerability in Japanese patients.Objective: This study was conducted to assess the efficacy and tolerability of atorvastatin in Japanese patients with hypercholesterolemia.Methods: Outpatients at the Hiramitsu Clinic who were receiving HMG-CoA reductase inhibitors for the treatment of hypercholesterolemia were enrolled in this open-label study. Previous HMG-CoA reductase inhibitor therapy was discontinued, and patients were uniformly switched to atorvastatin 10 mg/d with no intervening washout period. Clinical laboratory values and serumlipid levels were used as safety indices, and achievement rates of target total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) levels were used to assess efficacy. Target TC/HDL-C levels in patients with Japan Atherosclerosis Society category B hypercholesterolemia (patients with risk factors) and category C hypercholesterolemia (patients with coronary heart disease) were <200/<120 mg/dL and <180/<100 mg/dL, respectively.Results: Seventy-nine patients (23 men, 56 women; mean [±SD] age, 63.9 ± 11.2 years) completed the study. The mean duration of atorvastatin therapy was 62.7 ± 9.0 days. The switch to atorvastatin produced significant reductions in mean levels of TC (from 212.8 ± 29.0 mg/dL to 165.7 ± 24.8 mg/dL; P < 0.001) and LDL-C (from 135.2 ± 24.3 mg/dL to 92.2 ± 20.7 mg/dL; P < 0.001). Achievement rates of target TC and LDL-C levels dramatically improved in patients with Japan Atherosclerosis Society category B or C hypercholesterolemia. In patients with category B hypercholesterolemia, the achievement rate improved from 30.8% (20/65) at baseline to 87.7% (57/65) with regard to target TC levels and from 26.2% (17/65) to 92.3% (60/65) with regard to target LDL-C levels. In category C, the corresponding results were 30.0% (3/10) to 80.0% (8/10) and 10.0% (1/10) to 70.0% (7/10). No side effects sufficiently serious to warrant discontinuation of atorvastatin therapy were observed.Conclusion: In this study, atorvastatin was effective and well tolerated for the treatment of hypercholesterolemia in Japanese patients.