In what could be a landmark study recently published in the Journal of the American Medical Association , researchers conducted a meta-analysis of the data from the Copenhagen City Heart Study (over 9000 persons with two decades of followup), the Copenhagen General Population Study (an ongoing study of over 30,000 persons), and the Copenhagen Ischemic Heart Disease Study (2500 persons referred for angiography). The conclusion, "Lower plasma levels of HDL cholesterol due to heterozygosity for loss-of-function mutations in ABCA1 were not associated with an increased risk of IHD." The lead investigator added, "The principal finding of this study is that heterozygosity for loss-of-function mutations in ABCA1 associated with substantial, lifelong lowering of plasma levels of HDL cholesterol, but not with corresponding higher levels of plasma triglycerides or atherogenic remnant lipoproteins, did not predict an increased risk of ischemic heart disease."
Now, let's review their findings - this time in English! The researchers looked for mutations in a key gene ( ABCA1 ) that lowers HDL Cholesterol (HDL) and reduces cholesterol efflux from the artery wall but does not affect triglycerides. As expected, the group with the mutations had an HDL that averaged 17mg/dl lower than the general population and that 17mg/dl reduction should have translated to a 70% risk increase based on the results of the Copenhagen City Heart Study. However, this low HDL group did not appear to have any more risk than average. It was only in the presence of low HDL and high triglycerides that they found higher heart disease risk.
The findings suggest that, although low HDL is consistently associated with higher heart disease risk, it is not, by itself, a cause. The practical implication is not to dismiss low HDL as a marker for heart disease but to question its true role. It further suggests that simply raising HDL (as is the target of many new drugs such as CETP antagonists) is not enough and it must be considered in relation to other factors that often appear in conjunction with low HDL such as high triglycerides. Of course, this provides additional validation for the 60/60/60 Track Your Plaque principle. Keep that HDL high and those TGs low!
Man, and I thought quantum physics was wacky stuff! Study after study has shown that higher HDL is strongly associated with cardiovascular health. HDL Cholesterol efflux mechanisms and the entire mechanics of reverse cholestrol transport have been proposed , studied, and experimentally observed. Now this!
In what could be a landmark study recently published in the Journal of the American Medical Association , researchers conducted a meta-analysis of the data from the Copenhagen City Heart Study (over 9000 persons with two decades of followup), the Copenhagen General Population Study (an ongoing study of over 30,000 persons), and the Copenhagen Ischemic Heart Disease Study (2500 persons referred for angiography). The conclusion, "Lower plasma levels of HDL cholesterol due to heterozygosity for loss-of-function mutations in ABCA1 were not associated with an increased risk of IHD." The lead investigator added, "The principal finding of this study is that heterozygosity for loss-of-function mutations in ABCA1 associated with substantial, lifelong lowering of plasma levels of HDL cholesterol, but not with corresponding higher levels of plasma triglycerides or atherogenic remnant lipoproteins, did not predict an increased risk of ischemic heart disease."
Now, let's review their findings - this time in English! The researchers looked for mutations in a key gene ( ABCA1 ) that lowers HDL Cholesterol (HDL) and reduces cholesterol efflux from the artery wall but does not affect triglycerides. As expected, the group with the mutations had an HDL that averaged 17mg/dl lower than the general population and that 17mg/dl reduction should have translated to a 70% risk increase based on the results of the Copenhagen City Heart Study. However, this low HDL group did not appear to have any more risk than average. It was only in the presence of low HDL and high triglycerides that they found higher heart disease risk.
The findings suggest that, although low HDL is consistently associated with higher heart disease risk, it is not, by itself, a cause. The practical implication is not to dismiss low HDL as a marker for heart disease but to question its true role. It further suggests that simply raising HDL (as is the target of many new drugs such as CETP antagonists) is not enough and it must be considered in relation to other factors that often appear in conjunction with low HDL such as high triglycerides. Of course, this provides additional validation for the 60/60/60 Track Your Plaque principle. Keep that HDL high and those TGs low!
Wacky stuff!
HeartHawk