Cholesterol Particle Size and Number Can Predict Heart Attack, Says University of Pittsburgh Researcher at AHA Meeting
ANAHEIM, CA, November 14, 2001 — The size and number of lipoproteins in the body can predict an individual's risk of heart attack, particularly in women, reported a University of Pittsburgh researcher at this week's American Heart Association (AHA) meeting.
"The higher the number of small LDL particles, the greater the woman's chances of a heart attack," said Lewis Kuller, M.D., professor and chair, department of epidemiology, University of Pittsburgh Graduate School of Public Health. "We found that heart attack risk was as much as 2.45 times more likely for women who had the largest number of small LDL particles compared to women who had the lowest number of small LDL particles."
These findings are strikingly important, as heart disease is the number-one killer of women in the United States, and almost 60 percent of the people who die of a heart attack die suddenly outside of a hospital.
By assessing this new marker, researchers believe that physicians may be in a much better position to initiate therapy to reduce the risk of heart attack or prevent atherosclerosis before it becomes full-blown disease. Dr. Kuller points out that lipoprotein size and distribution can be improved not only by drug therapy, but by diet and exercise as well for many individuals.
Dr. Kuller presented results of a study that evaluated lipoprotein size and number from blood samples taken from 1,849 participants in the Cardiovascular Health Study. The project evaluated stored blood samples from patients who were followed for five to six years. Participants were aged 65 and older, with one group representing the controls, a second group that ultimately experienced heart attack and a third group free of subclinical or clinical cardiovascular disease.
Results showed that women who had experienced a heart attack had large numbers of small LDL (low-density lipoprotein) particles. The association was stronger in women than in men.
Small LDL particles are more likely than large particles to cause the buildup of plaque along arterial walls. LDL cholesterol is often referred to as "bad" cholesterol when compared with HDL (high-density lipoprotein), or "good" cholesterol.
Although lipoproteins were once difficult and costly to measure, nuclear magnetic resonance imaging technology (MRI) now makes an analysis of lipoprotein size and number a relatively simple task.