A reader writes:
Dr. Lasater, I’m a 55-year-old woman who has enjoyed fairly good health my entire life. My tennis partner, a woman who is my age, recently had a heart attack. She feels quite fortunate to have survived and is now getting back to her usual activity level, but she and her family are still concerned – and quite puzzled – that this happened to her. She has never smoked, there has never been any history of heart problems in her family, her blood pressure has never been a problem, and even though she is slightly overweight, she has always been fairly active physically. She had seen her doctor just a month before and was told that her cholesterol was “fine.” I know that having our cholesterol checked is important, but are there any additional tests that could be performed to see whether someone is at risk for having a heart attack or a stroke?
You, as well as your friend and her family, are right to be concerned. One in two people die from cardiovascular disease every year; this is more than the next seven causes of death combined, including cancer.
Cardiovascular disease is the number one cause of death in American women – yes, women! One of the major risk factors for cardiovascular disease is high cholesterol and it is also the most treatable. Yet traditional cholesterol testing fails to identify up to 40-50% of the population at risk for cardiovascular disease and death. There are a number of additional tests that can be quite useful to determine whether one is at significant risk of having a heart attack or stroke. Arguably the most important of these is to have one’s Particle Test performed. Most physicians order what many experts consider the wrong test to gauge heart disease risk: a standard cholesterol panel, which shows the levels of low-density lipoprotein (LDL) and non-high density lipoprotein (non-HDL) cholesterol. What they should request instead (or in addition) is an inexpensive assay for a blood protein known as apolipoprotein B (apoB), which indicates the number of “bad cholesterol”-laden particles circulating in the blood—a truer indicator of the threat to our arteries than absolute cholesterol levels, some researchers believe. The use of routine apoB tests, which are now relatively inexpensive, would identify millions more patients who could benefit from cholesterol-cutting therapies and would spare many others from unnecessary treatment. Across the United States, patients who have the highest apoB readings will suffer nearly 3 million more heart attacks, strokes, and other cardiovascular events in the next 15 years than will people with the lowest levels. As lipidologist Dr. Daniel Rader of the University of Pennsylvania Perelman School of Medicine puts it, the question of whether LDL cholesterol is the best measure of cardiovascular risk now has a clear answer: “No.” In women after menopause, testing for elevated apolipoprotein B is especially important because the drop in hormone levels at menopause results in more apoB being produced by the liver, a risk increase which usually “flies under the radar” of the usual cholesterol/lipid tests.
Another test that is important, especially if there is a history of heart disease without high cholesterol in one’s family, is for Lipoprotein (a). The “LP little a,” as it is called, is a form of Low Density Lipoprotein (LDL) in which another protein, called Apo(a), is attached to each LDL particle as it carries cholesterol around in the body. Having elevated blood levels of Lipoprotein (a) raises a person’s risk of heart attack and stroke beyond what is normally seen from elevated LDL cholesterol alone. This is believed to be due to the Apo(a) protein, which may reduce the body’s ability to break down clots. The typical lipid/cholesterol test will not reveal if this bad boy is present in increased numbers, so it must be ordered specifically. Elevated Lipoprotein (a) is usually inherited from one parent. About 1 in 4 people in the population are believed to have elevated blood levels of Lipoprotein (a). African-Americans may have higher levels. Besides genetics, Lipoprotein (a) levels may result from increased intake of some types of fats, and some medical conditions.
One more test that is worth consideration is high-sensitivity C-reactive protein (hs-CRP), a measure of inflammation in the body. When inflammation is present, the plaque in our arteries becomes unstable and is thus more likely to rupture, causing a heart attack or stroke. One major published study, the JUPITER Study, found that treating elevated CRP is even more beneficial in preventing cardiovascular events than is treating high LDL cholesterol.
You should ask your doctor to consider ordering these additional tests, as they are relatively inexpensive, can help further stratify one’s cardiovascular risk, and if elevated can be treated.
Steve R. Lasater MD practices Age Management Medicine, Hormone Replacement, and Clinical Lipidology at Optimal Wellness Medical Group, 5070 Cascade Road SE, Suite 210, Grand Rapids, MI 49546. See his website at http://www.OptimalWellnessMedical.com