HDL Particle Concentration is a Better Predictor of Coronary Heart Disease - Honigberg

HDL Particle Concentration is a Better Predictor of Coronary Heart Disease Risk than HDL Cholesterol

       

Robert Honigberg, MD

Several recent, high-profile clinical trial failures of experimental high density lipoprotein (HDL)-raising therapies has prompted members of the scientific and medical communities to question the prognostic value of HDL as an indicator of coronary heart disease (CHD) risk. However, new research suggests that we should update clinical guidelines with a more predictive measurement of HDL-related risk.

The study, which evaluated the independent associations of high density lipoprotein cholesterol (HDL-C) and high density lipoprotein particle (HDL-P) concentrations with CHD, suggests that HDL-P may be a more accurate indicator of cardiovascular risk than HDL-C. The findings were published in the current issue of the Journal of the American College of Cardiology.

Researchers analyzed blood samples obtained at study onset from 5,598 middle-aged men and women free of cardiovascular disease who participated in the Multi-Ethnic Study of Atherosclerosis (MESA), a prospective observational study initiated and overseen by the National Heart, Lung and Blood Institute. Participants were followed for a mean of six years for incident CHD events—including angina, heart attack, and coronary heart disease death.

The researchers concluded that baseline levels of HDL-C and HDL-P were both inversely associated with CHD events and carotid atherosclerosis in this study population. However, after adjusting each HDL measure for the other and for LDL-P, joint analysis demonstrated that the inverse relationship for CV risk persisted for HDL-P but no longer existed for HDL-C. The more consistent inverse association between cardiovascular endpoints and HDL-P has also been shown in other studies including the HPS, MR-FIT, EPIC-NORFOLK and VA-HIT trials. In the accompanying editorial, Emil deGoma and Dan Rader noted that HDL-P may be more useful to refine cardiovascular risk and to evaluate novel HDL-directed therapies.

In light of this study’s findings, it is likely that more research will be conducted which extends beyond traditional HDL-C measurement to sort out the different functional properties of HDL. We at LipoScience contend that measuring HDL-P in clinical practice can lead to better patient treatment decisions, particularly as the LDL particle number is brought under control. Obviously this is a provocative subject, and I’d love for you share your thoughts in the comment section.
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It's the Calcium Score Stupid! - HeartHawk

Tuesday, November 23, 2010

JUPITER to Earth: It's the Calcium Score Stupid!

Well, well, well! A funny thing happened on the way to the "statin forum." Astra-Zeneca, in a bald-faced attempt to broaden the market for its statin product Crestor, ended up proving beyond a shadow of a doubt that heart scans and calcium scoring is the most powerful predictor of heart attacks in asymptomatic people.

A post hoc analysis of the MESA study population using JUPITER criteria revealed at 25-fold increase in risk for persons having a positive calcium score. These two studies were fairly large so it was adequately powered to deliver results with a high degree of confidence.

For years docs like Bill Davis and Bill Blanchet have been screaming this from the hilltops and it something every Track Your Plaque practitioner knows. If you have a positive calcium score you have coronary artery disease and your risk of a heart attack skyrockets. Fortunately, it also gives you often decades of warning so you can actually DO something about it. Coupled with technologies like advanced lipoprotein you can find the root causes and correct them.

So, "thank you" Atra-Zeneca. I know you did it for the money - but what the heck - you might end up having helped save some lives in spite of it!

Now darn it, go out talk to your doc about getting that heart scan if you have any doubts about having the seeds of heart disease in your arteries.

Looking out for your health,
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Who is HeartHawk?
I am a numbers guy, an engineer, MBA, and for the real numbers geeks, a Six Sigma Black Belt (statistics on steroids). I am also a heart disease sufferer. It took my mother, her brother, and their father. One minute they were alive and symptom free, the next they were dead. No good-byes, just gone. So, I became a heart health activist and resolved that I will die some other way. This blog is about my journey to save myself and others, unearthing advances and atrocities, separating hope from hype, and delivering the unvarnished truth about curing heart disease, both good and bad. So, hold on tight. I promise you a hell of a ride!

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Heart Calcium Scan Most Effective in Predicting Risk of Heart Disease

Heart Calcium Scan Most Effective in Predicting Risk of Heart Disease

Released:8/20/2012 10:45 AM EDT
Source:Wake Forest Baptist Medical Center

Newswise — WINSTON-SALEM, N.C. – Aug. 21, 2012 – Heart calcium scans are far superior to other assessment tools in predicting the development of cardiovascular disease in individuals currently classified at intermediate risk by their doctors, according to researchers at Wake Forest Baptist Medical Center.

The test, known as coronary artery calcium (CAC), uses a CT scan to detect calcium build-up in the arteries around the heart. The study findings are presented in the Aug. 22 issue of the Journal of the American Medical Association.

Current medical guidelines recommend classifying individuals as high, intermediate or low risk using the Framingham Risk Score (FRS), a cardiovascular risk-prediction model. However, doctors realize that the model isn’t perfect and that the intermediate group actually includes some individuals who could benefit from more aggressive drug therapy, as well as individuals who could be managed solely with lifestyle measures.

“We know how to treat patients at low and high risk for heart disease, but for the estimated 23 million Americans who are at intermediate risk, we still are not certain about the best way to proceed,” said Joseph Yeboah, M.D., assistant professor of cardiology at Wake Forest Baptist and lead author of the study.

The Wake Forest Baptist study, which was funded by the National Heart Lung and Blood Institute (NHLBI) of the National Institutes of Health, evaluated which of the top-tier assessment tools best identified people within the intermediate group who were actually at higher or lower risk.

Determining the relative improvements in prediction afforded by various tests, especially when used in conjunction with the FRS, could help identify intermediate-risk people who may benefit from more aggressive primary prevention interventions, including the use of aspirin and the setting of lower targets for drug treatment of LDL cholesterol and blood pressure, Yeboah said.

Using data from the NHLBI’s Multi-Ethnic Study of Atherosclerosis (MESA) study, the researchers did a head-to-head comparison of six top assessment tests for cardiovascular risk prediction in intermediate-risk people: CAC score, ankle-brachial index, brachial flow mediated dilation, carotid intima-media thickness, high sensitivity C-reactive protein and family history of heart disease.
Of the 6,814 total MESA participants from six communities across the country, 1,330 were considered at intermediate risk and were included in this study. The researchers determined that the CAC score proved the best in predicting which among the intermediate-risk people would go on to have heart disease in the ensuing 7.5 years (average) of follow-up observation.

“If we want to concentrate our attention on the subset of intermediate-risk patients who are at the highest risk for cardiovascular disease, CAC is clearly the best tool we have in our arsenal to identify them. However, we have to look at other factors such as costs and risks associated with radiation exposure from a CT scan before deciding if everyone in the intermediate group should be screened,” Yeboah said.

Additional research is needed to explore the costs, benefits and risks of widespread use of CAC screening in people at risk of heart disease, he said.

The study’s co-authors are: Robyn L. McClelland, Ph.D., University of Washington, Seattle; Tamar S. Polonsky, M.D., University of Chicago; Gregory L. Burke, M.D., Jeffery J. Carr, M.D., and David M. Herrington, M.D., Wake Forest Baptist; Christopher T. Sibley, M.D., National Institutes of Health; Daniel O’Leary, M.D., Tufts Medical Center; David C. Goff Jr., M.D., Ph.D., University of Colorado; and Philip Greenland, M.D., Northwestern University
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Measuring HDL Particles as Opposed to HDL Cholesterol Is a a Better Indicator of Coronary Heart Disease

Measuring HDL Particles as Opposed to HDL Cholesterol Is a a Better Indicator of Coronary Heart Disease, Study Suggests

ScienceDaily (July 11, 2012) — Until recently, it seemed well-established that high-density lipoprotein (HDL) is the "good cholesterol." However there are many unanswered questions on whether raising someone's HDL can prevent coronary heart disease, and on whether or not HDL still matters. A team of researchers at Brigham and Women's Hospital (BWH), the University of Pittsburgh Graduate School of Public Health (GSPH) and other institutions, have discovered that measuring HDL particles (HDL-P) as opposed to HDL cholesterol (HDL-C) is a much better indicator of coronary heart disease (CHD), and that HDL does indeed, still matter.

This study will be electronically published July 11, 2012 and will be published in the August 7th print issue of the Journal of American College of Cardiology.

"Several recent failures of HDL-raising drugs and a genetic study have generated doubt that circulating levels of HDL in the blood are causally related to heart disease, and that raising HDL is a promising therapeutic approach," said Rachel Mackey, PhD, principal investigator of the study and assistant professor of epidemiology at GSPH.

Most previous studies of HDL have looked at the cholesterol to assess CHD risk, not many have examined the particle count. The research team analyzed data from the Multi-Ethnic Study of Atherosclerosis (MESA), an NIH funded multiethnic study. The researchers focused on a subset of data of 5,500 middle-aged men and women, over the age of 45. They looked at the quantity of HDL particles (HDL-P) in addition to the quantity of cholesterol carried by the particles (HDL-C), which has historically been used to measure HDL.

"HDL cholesterol is only one property of HDL particles -- it's like cargo on a ship, one can look at HDL cholesterol, which is one type of the cargo that is carried on the ship, or one can look at the number of ships. In our study, we found that the number of HDL particles had stronger cardio-protection than HDL cholesterol," explained Samia Mora, MD, a physician in the Cardiovascular and Preventive Divisions at BWH and senior author on the study.

The study suggests that it's important to not only measure HDL cholesterol, but to experiment with other ways of measurement, such as HDL particles. "Before we lose confidence in the potential of raising HDL to benefit patients, there needs to be more research extending beyond HDL cholesterol measurement," Explained Dr. Mackey.
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