Slippery Slope of Triglycerides

For years, the scientific and medical communities have pondered the role of triglycerides in cardiovascular disease (CVD) and mortality risk. Although several studies have shown a relationship between elevated triglyceride levels and CVD, the degree to which triglycerides are independently associated and whether triglycerides directly cause CVD has been hotly debated. This is in contradistinction to the role of low-density lipoprotein cholesterol (LDL-c) where the direct relationship between LDL-c and CVD is clear. During the years, several pieces of evidence have suggested an independent association between elevated serum triglycerides and CVD; however, the firmness of this conclusion has been seen as tenuous. In fact, a recent large study (>300 000 participants) did not find triglycerides to be an independent risk factor for CAD when adjusted for high-density lipoprotein cholesterol and non–high-density lipoprotein cholesterol. Most likely, the confusion comes because it can be difficult to know whether the triglycerides themselves are the cause of the increased risk or merely a marker of increased risk. High triglycerides usually occur in conjunction with a host of other abnormalities, such as insulin resistance, diabetes mellitus, low high-density lipoprotein cholesterol obesity, and hypertension, thus it is difficult to disentangle which is the true causal factor.