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Dr. Brian Denton
A new study from North Carolina State University shows that the vast majority of patients at high risk for heart disease or stroke do a poor job of taking statins as prescribed. That’s especially unfortunate, because the same study shows that taking statins can significantly increase the quality and length of those patients’ lives.

“We found that only 48 percent of patients who have been prescribed statins are taking their prescribed dose on a regular basis after one year – and that number dips to approximately 27 percent after 10 years,” says Jennifer Mason, a Ph.D. student at NC State and lead author of a paper describing the study. Statins are a component of many current cardiovascular medical treatment guidelines. They lower cholesterol levels and may significantly reduce the risk of heart attack and stroke, particularly in patients that are considered to be at high risk.

The researchers also found that, for high-risk patients, high adherence to a prescribed statin regimen may increase quality-adjusted life years (QALYs) by as much as 1.5 years compared to low adherence – and up to two years compared to not taking statins at all. Low adherence means a patient is taking the statins irregularly or at less than the prescribed dosage. QALYs are established metrics for measuring the effect of health conditions, such as heart disease and stroke, on quality of life.

The study used operations research models to look specifically at patients who have type 2 diabetes, because they are at particularly high risk for heart disease, heart attack and stroke.

“These findings suggest that adherence-improving interventions – such as patient education or electronic reminders to take medications – can significantly improve the quality and length of life, particularly for high-risk patients,” says Dr. Brian Denton, co-author of the paper and an associate professor in the Edward P. Fitts Department of Industrial & Systems Engineering at NC State.

The paper, “Optimizing Statin Treatment Decisions for Diabetes Patients in the Presence of Uncertain Future Adherence,” is forthcoming from the journal Medical Decision Making. The research was funded by the Agency for Healthcare Research and Quality (AHRQ) and the National Science Foundation (NSF). The paper was co-authored by Dr. Darin England; Drs. Steven Smith and Nilay Shah of the Mayo Clinic College of Medicine; and Mr. Murat Kurt of the University of Pittsburgh.

“Optimizing Statin Treatment Decisions for Diabetes Patients in the Presence of Uncertain Future Adherence”

Authors: Jennifer E. Mason and Brian T. Denton, North Carolina State University; Darin A. England; Steven A. Smith and Nilay D. Shah, Mayo Clinic College of Medicine; Murat Kurt, University of Pittsburgh

Published: forthcoming, Medical Decision Making

Abstract: Background: Statins are an important part of the treatment plan for patients with type 2 diabetes. However, patients who are prescribed statins often take less than the prescribed amount or stop taking the drug altogether. This suboptimal adherence may decrease the benefit of statin initiation.

Objective: To estimate the influence of adherence on the optimal timing of statin initiation for patients with type 2 diabetes.

Method: The authors use a Markov decision process (MDP) model to optimize the treatment decision for patients with type 2 diabetes. Their model incorporates a Markov model linking adherence to treatment effectiveness and long-term health outcomes. They determine the optimal time of statin initiation that minimizes expected costs and maximizes expected quality-adjusted life years (QALYs).

Results: In the long run, approximately 25% of patients remain highly adherent to statins. Based on the MDP model, generic statins lower costs in men and result in a small increase in costs in women relative to no treatment. Patients are able to noticeably increase their expected QALYs by 0.5 to 2 years depending on the level of adherence.

Conclusions: Adherence-improving interventions can increase expected QALYs by as much as 1.5 years. Given suboptimal adherence to statins, it is optimal to delay the start time for statins; however, changing the start time alone does not lead to significant changes in costs or QALYs.

CINCINNATI—University of Cincinnati (UC) researchers have determined the structure of human HDL cholesterol and say the finding could help explain how this “fat packet” protects against cardiovascular diseases, including heart attack and stroke.

The study, led by W. Sean Davidson, PhD, professor in UC’s pathology and laboratory medicine department, appears online ahead of print March 13, 2011, in the journal Nature Structural & Molecular Biology.

HDL (high-density lipoproteins) also known as “good cholesterol,” are packets of protein and fat that deliver fat to specific locations within the body.

There is an increasing effort to create drugs that help to raise levels of HDL working in conjunction with existing drugs that lower “bad cholesterol,” or low-density lipoproteins (LDL).

Studies of synthetically derived HDL have shown that an abundant protein in HDL, apolipoprotein A-I, plays a key role in HDL’s cardioprotective anti-inflammatory and anti-oxidative properties.

“Unfortunately, we’ve known very little about the molecular details that explain HDL’s protective effects,” says Davidson. “A major reason for this is an almost complete lack of understanding of HDL’s structure and how it interacts with other important plasma factors.”

Rong Huang, PhD, a post-doctoral fellow in Davidson’s laboratory, has isolated human HDL and analyzed its 3-D structure as it circulates in human plasma.

“Previous studies have only focused on synthetic HDL made in the test tube,” Davidson says. “By isolating human HDL, we were able to focus on the broad range of HDL particles actually circulating in humans.”

Team members used a series of sophisticated spectroscopic and mass spectrometric techniques to study HDL and have found that proteins of HDL form a cage-like structure that encapsulates its fatty cargo.

They determined that most of the HDL particles circulating in human plasma are remarkably similar in structure; however, they found evidence that the particles have a twisting or shock absorber-like motion that allows them to adapt to changes in particle fat content.

By determining the structure of HDL, Davidson and his team were able to conclude that the majority of physiological interactions occurring with HDL—including its twisting movements—occur at the particle surface, which is dominated by the cardioprotective protein apolipoprotein A-I.

This monopolization of the particle surface, Davidson says, suggests that other proteins have very little room to bind to HDL and probably have to interact with the protein itself, which could explain how apolipoprotein A-I plays such a dominant role in HDL function and its protective effects.

“This work presents the first detailed models of human plasma HDL and has important implications for understanding key interactions in plasma that modulate its protective functions in the context of cardiovascular disease,” says Davidson.

The study was funded by grants from the National Institutes of Health and its National Heart, Lung, and Blood Institute, as well as funds from the American Heart Association.

Penn State University Study Highlights Benefits of Phytosterols Found in Popular Snack Nut

FRESNO, Calif., Feb. 28, 2011 /PRNewswire/ — Newly released research from Penn State University highlights phytosterols, found in pistachios, may  improve cholesterol, a factor in cardiovascular health.

“We already know that pistachios are a naturally cholesterol-free food, but this new study suggests that phytosterols, or plant sterols, in pistachios may help to reduce the absorption of cholesterol,” said Constance Geiger, PhD, RD, CD and nutrition expert for the Western Pistachio Association. “Lowering cholesterol may reduce the risk of heart disease, so these findings give people even more reasons to snack on delicious pistachios.”

Plant sterols, naturally found in many fruits, vegetables and nuts, have been long studied for their cholesterol-lowering properties. These chemical compounds help lower total cholesterol levels by blocking the amount of cholesterol absorbed in the body.

Geiger offers three easy ways to eat pistachios for improved heart health:

• In the car: toss a bag of pistachios in the glove box for an easily accessible go-to food option when out running errands. Having a nutritious option within arm’s reach will help you avoid drive-thru binges.
• At home: fill a bowl with pistachios and set it out in the kitchen next to an empty bowl for shells for a healthier snack option.
• After the gym: pistachios may help lower blood cholesterol levels, and they also offer fiber, which satisfies hunger. Munch on pistachios on your way to or from the gym.  They offer more than 20 important nutrients to keep you powered up for the day.

Pistachio Facts

Pistachios are a naturally cholesterol-free snack that contains just 1.5 grams of saturated fat and 13 grams of fat, the majority of which comes from monounsaturated fat. A one-ounce serving of pistachios equals 49 nuts, which is more nuts per serving than any other snack nut. One serving of pistachios has as much potassium (300mg, 8 percent) as an orange (250mg, 7 percent), making it a nutritious snack choice or ingredient to incorporate into daily diets.

Research Details

The research abstract referenced in this press release is titled, “Dose-related effects of pistachios on plasma sterol concentrations in moderately hypercholesterolemic individuals” and co-authored by Holligan, S, Gebauer, SK, West, SG, Kay, CD, Kris-Etherton PM from the Department of Nutritional Sciences, Department of Biobehavioral Health, The Pennsylvania State University (University Park, PA, 16802), Beltsville Human Nutrition Research Center, Agricultural Research Service, USDA (Beltsville, MD, 20705) and School of Medicine, University of East Anglia (Norwich, NR4 7TJ, UK).

About the Western Pistachio Association

Western Pistachio Association is a non-profit voluntary trade association representing more than 400 growers in the United States. WPA is governed by an 18-member board of directors and is funded entirely by growers and independent processors with the shared goal of increasing global awareness of nutritious, American-grown pistachios.