This paper reviews the clinical trial data that offer insight into the question of whether, and in what groups of people, triglycerides might be an appropriate therapeutic target for the primary or secondary prevention of atherosclerotic cardiovascular disease. Two angiographic trials (the Lopid Coronary Angiography Trial and the Bezafibrate Coronary Atherosclerosis Intervention Trial) and three clinical endpoint trials (the Helsinki Heart Study, the Bezafibrate Infarction Prevention Study, and the VA HDL Intervention Trial) are reviewed. Hypertriglyceridemia per se is probably not an appropriate therapeutic target for the prevention of atherosclerotic cardiovascular disease because it is a poor marker of atherogenic risk and because there have been no clinical trials that have directly addressed the question of whether lowering the triglyceride level reduces the number of clinical events. The studies reviewed here, however, suggest that patients with established coronary heart disease and a high triglyceride level, in association with either a low high-density lipoprotein-cholesterol level or perhaps other features of the metabolic syndrome, such as obesity, diabetes, or hypertension, may benefit from fibrate therapy. For patients without established coronary heart disease, it is reasonable to consider hypertriglyceridemia as a risk marker prompting the aggressive treatment of other risk factors such as hypertension, diabetes, high low-density lipoprotein-cholesterol, and obesity.
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This post hoc subgroup analysis of the HHS was one of the first papers to suggest that multivariable modelling was not the most useful way to look at the relationship between triglyceride level and the occurrence of clinical events. When the joint effects of lipids were considered in this stratified analysis, the greatest benefit of gemfibrozil was seen in patients with a high LDL: HDL ratio and a high level of triglycerides.
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