The results, published in an Article in this week's Lancet, are from a major international consortium led by Dr Nadeem Sarwar and Professor John Danesh of the University of Cambridge. The findings encourage the conduct of trials of medicines that can lower levels of triglyceride fats.
Coronary heart disease is the leading cause of death and disability worldwide, responsible for about 7 million deaths every year. It is well known that high levels of bad (ie, LDL) cholesterol in the blood can cause heart disease, and this has lead to development of medicines that lower levels of LDL cholesterol to combat heart disease. By contrast, the relevance to heart disease risk of other types of blood fat, such as triglycerides, is not established.
Triglycerides, which are produced by the liver or derived from food, are a major source of energy in humans. Despite decades of research, it has remained uncertain whether raised blood levels of triglycerides cause heart disease. The new study has involved a novel approach that uses genetic information to mimic aspects of a drug trial. This so-called "Mendelian randomisation" analysis involved comparison of heart disease risk in people who have inherited different versions of a gene known to influence blood triglyceride levels. In analysis of 350,000 people from 101 studies, the researchers showed that people with a genetically-programmed tendency for higher triglyceride levels also had a greater risk of heart disease.
According to Dr Sarwar, "Although these genetic findings are consistent with a causative role for triglyceride fats in the development of heart disease, they do not replace the need for large randomised clinical trials of medications that can lower blood triglycerides. Such trials should help establish whether lowering triglyceride levels can reduce the risk of heart disease."
In an accompanying Comment, Dr Guillaume Pare and Dr Sonia S Anand, Population Genomics Program, Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, ON, Canada, say: "[This] experiment provides firm evidence for the association of [this genetic variant] on triglycerides and risk of coronary heart disease...the true nature of triglycerides' effect on coronary risk still needs further clarification."
Source
The Lancet