Raising Good Cholesterol May Cut Heart Risk in Diabetes Patients

November 12, 2012

Raising Good Cholesterol May Cut Heart Risk in Diabetes Patients

Suma Vupputuri, PhD, an investigator for the Kaiser Permanente Health Research Center in Atlanta and his co-researchers have published the results of a study they conducted online in the American Journal of Cardiology recently. The findings indicate that increased levels of HDL, ‘good cholesterol’ could help to minimize the risk of stroke or heart disease in those suffering type 2 diabetes.

The study consisted of an investigation into 30,067 type 2 diabetes patients by researchers from Kaiser Permanente Health Research Center. The patients’ HDL, ‘good’ cholesterol levels were recorded twice over a 2 year period between the years 2001 and 2006. The researchers sought an association between HDL levels and the risk of being hospitalized because of stroke or heart disease.

The diabetes sufferers whose HDL levels varied the most with the highest and lowest levels were compared to those whose levels remained stable. The risk of hospitalization was derived after investigation into these figures.

It was found that for every 5-mg/dL increase in HDL cholesterol there was a 4% drop in the risk of hospitalization because of heart disease and stroke. However the investigation identified that a reduction of at least 6.5 mg/dL was related to an 11% increased chance of hospitalization. This caused the researchers to put forward, “that the prevention of a HDL cholesterol decrease might be at least as important as increasing the HDL cholesterol level”.

The National Cholesterol Education Program, is a project of the National Heart, Lung, and Blood Institute, and it considers HDL under 40 mg/dL as a risk factor for heart disease and stroke. With this as background, it is known that of all type 2 diabetes sufferers 50% are classed as having low HDL. Women have HDL levels below 50 mg/dlL, and for men that figure is below 40 mg/dL.

Even after producing these findings the researchers remain cautious and acknowledge that the risk of heart attacks and strokes has not been proven to reduce because of increased levels of HDL. They say, “perhaps because safe and effective agents that substantially increase the HDL cholesterol level remain elusive”.

HDL can be raised by changes to lifestyle leading to heart risk cut

Suma Vupputuri, accepts that a major drawback of the study was the limited information that the researchers had on the methods used by the participants to raise their HDL. It is explained that changing your lifestyle can increase your HDL. Increasing the exercise that you do, stop smoking and losing weight are all factors known to increase the levels of HDL in your body. Yet at the same time these factors lower the risk of stroke or heart disease. It’s a bit of a chicken and egg scenario. Is the reduced risk of hospitalization because of the increased levels of HDL or are they just a by product of the steps the patient took?

On these lines Vupputuri expands that perhaps those cases with lower levels of HDL, and hence increased risk of hospitalization because of heart disease or stroke could be down to the individual gaining weight and not the lowered levels of HDL.

In spite of these issues, Vupputuri says, “I think the general message, certainly, from our paper, is yes, raising HDL is going to improve your cardiovascular outcomes”. This can be achieved by changing lifestyle which gives other health benefits too.

Steven Grover, MD, MPA, director of the McGill University’s Cardiovascular Improvement Program in Montreal, is in agreement with Vupputuri when he says, “There’s enough supportive evidence from clinical trials that there’s good reason to believe raising HDL will work”. He is talking about the benefits of lower risk of heart disease and stroke.

Grover conducted a study in 2009 which did not target type 2 diabetes patients and so had fewer type 2 diabetes sufferers in the group. The study found yet more benefits than Vupputuri’s study.

In addition to lifestyle changes there are other ways to raise HDL. Statins are known to be beneficial, however they are more effective at lowering LDL, which is considered to be the ‘bad’ cholesterol. Naicin, which is a vitamin, can raise HDL levels, as can gemfibrozil, which is a fibrate. However because these are both generic they have not attracted as much financial support as statins have.

The National Heart, Lung and Blood Institute terminated a clinical trial researching niacin recently. The trial used niacin in large doses with an extended release but the trial was ended 18 months prematurely because using statins alone were more effective at reducing the risk of stroke or heart disease.

In 2006 Pfizer, the pharmaceutical company, tried to develop an HDL-raising drug. However the project was concluded when it was found that the drug, torcetrapib, instead of reducing risk of death and heart disease had the opposite effect. However there has been progress on another drug which works in a similar fashion to torcetrapib. The drug dalcetrapib appears to be raising levels of HDL safely, but the process is still in early days and all results and findings are still classed as preliminary. Larger scale research is now required to confirm that the levels of safety and effectiveness are as indicated.

Tags: ,

Category: Articles