New recommendations spark a Cardiovascular Controversy
Cardiovascular disease remains the number one cause of death in the United States.
Heart disease, stroke and other cardiovascular diseases killed more than 787,000 Americans and accounted for one in six deaths in the U.S. in 2010, the most recent year for which statistics from the American Heart Association (AHA) are available.
The seriousness of these statistics is incontrovertible. What remains under some debate, though, is how to manage two of the chief risk factors for cardiovascular disease—cholesterol and blood pressure—and new guidelines from the AHA and other experts have only added to the controversy.
Proponents say the new guidelines allow for more individualized treatment of cholesterol and high blood pressure (hypertension), while identifying patients in greatest need of treatment. Critics contend that the new recommendations abandon important, motivating therapeutic goals for optimizing cholesterol, will require more patients to take cholesterol-lowering statin drugs and loosen the cutoff at which patients should receive blood pressure treatment.
Regardless of the debate, a local expert emphasizes that patients with heart disease, high cholesterol or hypertension should continue to work with their physicians to reduce their cardiovascular risk.
“A lot of times when this type of news comes out, one fear that I have is that patients sometimes misinterpret the news and suddenly stop taking their medications and lapse back into their usual habits,” says Dr. Krishna Tummalapalli, a cardiologist with Highlands Hospital in Connellsville and the University of Pittsburgh Medical Center. “That can backfire, and they can miss the key message that hypertension control and cholesterol control are two of the most important things we can do, in addition to lifestyle changes, to make an impact on cardiovascular problems.”
The new guidelines for managing cholesterol serve as an update to recommendations from the Adult Treatment Panel’s third report (ATP III), last updated in 2004. ATP III identified specific target levels of low-density lipoprotein (LDL, “bad”) cholesterol that patients and their doctors should strive to reach to reduce their cardiovascular risk from atherosclerosis, or “hardening” of the arteries.
The AHA and American College of Cardiology based the new recommendations for cholesterol management solely on randomized, controlled trials, the “gold standard” of medical research. They concluded that no evidence from these trials demonstrates that treating to specific LDL target goals improves patient outcomes.
So, the experts abandoned these target LDL levels and instead identified four patient groups that should be treated with cholesterol-lowering statin medications (see chart). Evidence suggests that statin therapy can reduce the risk of cardiovascular events, such as heart attacks, even in people with relatively low LDL levels.
“The point is when you really look at the medical literature, it’s very difficult to discern what the LDL goal should really be,” says Dr. John Schindler, an interventional cardiologist with the University of Pittsburgh Medical Center. “It’s more important for someone to be on therapy than it is to strive toward a specific goal.”
Some experts have considered the absence of specific LDL targets as a flaw in the new guidelines. The targets, they say, allow patients (and their doctors) to monitor their progress, motivate them to make healthful lifestyle changes and guide physicians in making treatment decisions. They also contend that by reviewing only randomized, controlled trials, the guidelines panel failed to consider scientific evidence supporting the use of LDL goals.
Schindler says the shift away from specific LDL targets will mean less frequent blood testing to monitor a patient’s cholesterol levels, although some testing will still be necessary.
“If we’re saying that we don’t know what the best LDL value is and if we don’t have a target that we’re shooting toward, what is the benefit to doing it?” he says. “From a patient perspective, some people are numbers driven, and we’ve driven into their heads that they need to know their LDL numbers. Now we’re saying forget about the numbers and just get on the medication and you’ll be fine. Some people will like that, but other people may not see that as a benefit.”
Know your risk
Among the more controversial features of the new guidelines is a new global risk calculator, which factors a patient’s age, gender, race, cholesterol level, blood pressure, diabetes and smoking status to estimate his or her 10-year risk of developing cardiovascular disease (the calculator is available at http://my.americanheart.org/cvriskcalculator).
Older recommendations called for drug therapy for patients with a 10-year risk of at least 10 to 20 percent, but the new guidelines recommend treatment for patients with a 10-year risk of only 7.5 percent, as determined by the risk calculator.
Critics claim that the new calculator places too much emphasis on age when gauging a person’s risk. For instance, according to the calculator, a 63-year-old white man and a 66-year-old African-American man will have a 7.5 percent 10-year risk of cardiovascular disease (and thus warrant statin treatment) even if they have optimal values of blood pressure, cholesterol levels and other risk factors.
Tummalapalli stresses that physicians must consider the individual characteristics of each patient, as well as a patient’s family history of cardiovascular disease, when assessing risk and making treatment decisions.
“Individualized risk would be the main focus of these new guidelines. Each patient is different,” Tummalapalli says. “None of these calculators will replace the clinical judgment of the doctor.”
Other experts have expressed concerns that the lower threshold for starting treatment will produce a drastic rise in the number of patients taking statin drugs, some of whom may gain little benefit while being exposed to a risk of statin side effects. The drugs may cause elevations in liver enzymes and blood sugar, muscle aches and, in rare cases, a potentially life-threatening muscle breakdown.
Tummalapalli says most people who experience statin complications develop them soon after starting therapy. For patients who can’t tolerate a particular statin regimen, a physician may adjust the dose, switch to a different statin or consider other cholesterol-lowering alternatives, he adds.
Schindler says millions of patients have used statins safely for many years, and the cardiovascular benefits that the drugs provide far outweigh their potential risks.
“If you have one of those four conditions outlined in the guidelines, you may end up being strongly encouraged to initiate a new medication,” he says. “This is a therapy that’s been shown to be effective. When you target the right population, the highest-risk group, with a drug that has known minimal side effect profiles, to me that’s an easy balance. I would say use these drugs to reduce cardiovascular events.”
Targeting high blood pressure
Hypertension has long been identified as a systolic blood pressure (the top number in the reading) of 140 mmHg or higher or a diastolic pressure of 90 mmHg or higher, and doctors have used medical therapy to reduce blood pressure below these thresholds.
However, in December, new guidelines from the Eighth Joint National Committee (JNC 8) essentially redefined hypertension in people age 60 and older. The guidelines recommend that these patients undergo treatment when their blood pressure exceeds 150 mmHg systolic or 90 mmHg diastolic, and the treatment should maintain blood pressure levels below these levels. In patients younger than age 60, as well as anyone with chronic kidney disease or diabetes, doctors should initiate treatment to keep blood pressure levels below 140 mmHg systolic or 90 mmHg diastolic, according to the guidelines.
The guideline authors noted that treatment does not need to be adjusted in older patients whose medical treatment is well tolerated and safely results in lower achieved systolic blood pressure (e.g. 140 mmHg).
As with the cholesterol recommendations, the hypertension treatment guidelines have stirred controversy.
“The American Heart Association and American College of Cardiology are not completely sold on this recommendation,” Tummalapalli says. “They’re not fully endorsing it. With this 150/90 number, I’m still cautious. Hypertension is a serious health risk and the number one cause of stroke and heart failure. We still need to be cautious. That’s not to say that based on the new guidelines we can relax our approach. Each patient has to follow his physician’s advice and ask questions.”
Other organizations have presented their own guidelines for managing blood pressure. For example, the AHA and ACC released a scientific advisory in November recommending the longstanding blood-pressure goal of less than 139/89 mmHg.
Tummalapali emphasizes that blood pressure management, as with cholesterol control, should be based on an individual patient’s overall health profile: “If the patient is otherwise in good health, with no history of stroke, no cardiovascular disease or diabetes, I may be more inclined to agree with the 150/90 recommendation in people over age 60. But if they have any history of heart disease or diabetes or a family history of stroke, I may be more vigilant.”
Lifestyle changes still key
Despite differences in opinions and recommendations, experts universally agree that healthful lifestyle changes are the cornerstone of cardiovascular risk reduction. Doctors recommend a heart-healthy diet such as the Mediterranean-style eating plan, which is low in saturated fat, trans fat and sodium and emphasizes consumption of fruits, vegetables, legumes and whole grains.
Exercise is another key to heart health, and studies have shown that engaging in regular physical activity can reduce blood pressure and raise levels of beneficial HDL cholesterol. Many experts recommend getting at least 30 to 45 minutes of daily aerobic exercise, such as walking, biking or swimming, on most days of the week.
And, if you’re overweight, work with your health-care professional to develop a diet and exercise plan that can help you shed pounds and reduce your cardiovascular risk.
“Sometimes even minor reductions in weight lead to significant clinical changes,” Schindler says. “If you just shave off the last 10 to 15 pounds of weight you put on, your blood pressure is going to come down and your cholesterol is going to come down. Those last 10 pounds do have real, negative effects with respect to cardiovascular disease.”