MacMahon S, Sharpe N, Gamble G, Hart H, Scott J, Simes J, White H
Department of Medicine, University of Auckland, New Zealand.
Circulation. 1998 May 12;97(18):1784-90. doi: 10.1161/01.cir.97.18.1784.
Cholesterol lowering in patients with above-average cholesterol levels has been shown to reduce the progression of atherosclerosis and lower the risk of coronary heart disease events. However, there has been uncertainty about the effects of cholesterol lowering in patients with average or below-average cholesterol levels.
In this study, 522 patients with a history of myocardial infarction or unstable angina and with baseline levels of total cholesterol between 4 and 7 mmol/L (mean, 5.7 mmol/L) were randomized to treatment with a low fat diet plus pravastatin (40 mg daily) or to a low fat diet plus placebo. Treatment with pravastatin reduced the levels of total cholesterol by 19%, LDL cholesterol by 27%, apolipoprotein B by 19%, and triglycerides by 13% (all 2P<.0001) and increased apolipoprotein A1 and HDL cholesterol levels by 4% (both 2P<.0005), in comparison with placebo. Carotid atherosclerosis was assessed from B-mode ultrasound measurements of the common carotid artery. After 4 years, mean carotid wall thickness had increased by 0.048 mm (SE=0.01) in the placebo group and declined by 0.014 mm in the pravastatin-treated group (SE=0.01) (2P for difference <.0001). The effect of treatment on wall thickness was similar in three groups classified by tertiles of total cholesterol at baseline, with mean levels of 4.8, 5.7, and 6.6 mmol/L, respectively (2P for interaction >.8).
Treatment with pravastatin reduced the development of carotid atherosclerosis among patients with coronary heart disease and a wide range of pretreatment cholesterol levels. Treatment with this agent prevented any detectable increase in carotid wall thickening over 4 years of follow-up.
胆固醇水平高于平均水平的患者降低胆固醇已被证明可减缓动脉粥样硬化进展并降低冠心病事件风险。然而，胆固醇水平处于平均或低于平均水平的患者降低胆固醇的效果一直存在不确定性。
在本研究中，522例有心肌梗死或不稳定型心绞痛病史且总胆固醇基线水平在4至7 mmol/L（平均5.7 mmol/L）之间的患者被随机分为接受低脂饮食加普伐他汀（每日40 mg）治疗组或低脂饮食加安慰剂组。与安慰剂相比，普伐他汀治疗使总胆固醇水平降低19%，低密度脂蛋白胆固醇降低27%，载脂蛋白B降低19%，甘油三酯降低13%（均P<0.0001），并使载脂蛋白A1和高密度脂蛋白胆固醇水平升高4%（均P<0.0005）。通过对颈总动脉进行B型超声测量来评估颈动脉粥样硬化。4年后，安慰剂组颈总动脉平均壁厚度增加了0.048 mm（标准误=0.01），普伐他汀治疗组颈总动脉平均壁厚度下降了0.014 mm（标准误=0.01）（差异的P<0.0001）。根据基线总胆固醇三分位数分类的三组患者中，治疗对壁厚度的影响相似，三组患者的平均水平分别为4.8、5.7和6.6 mmol/L（交互作用的P>0.8）。
普伐他汀治疗可减少冠心病患者及广泛的治疗前胆固醇水平范围内颈动脉粥样硬化的发生。在4年的随访中，使用该药物治疗可防止颈动脉壁增厚出现任何可检测到的增加。
