Advances in Heart Medicines: When Diet and Exercise Aren't Enough
Hypertension and high cholesterol have been diagnosed in more than 75 million US adults. It has become a classic line in American doctor's offices and TV ads: Diet and exercise weren't enough. Certainly, genes, increasing age, and diseases that weaken the heart or arteries contribute. But lifestyle greatly affects blood pressure and plaque buildup in arteries, too. Poor habits and deliberate choices about diet and physical activity can override even healthy genes.
In many patients, purposeful actions to change family norms, like avoiding salt at the dinner table or walking after dinner instead of watching TV, can keep arteries open and keep blood pressure low and steady. Sometimes, though, diet and exercise changes really aren’t enough. Medicines become essential to prevent life-threatening complications like heart attacks and strokes.
New and old drugs to control blood pressure
A few established classes of drugs have been available to treat high blood pressure for decades, although recommendations for their best use are updated regularly. In 2017, the joint guideline for physicians recommended using medicine for hypertension in most patients age 60 years or older when the systolic blood pressure (the top number) was at least 150 and suggested that aggressive control (to systolic < 120 or 140 mmHg) may not be necessary in every patient. If a single drug cannot meet the goal even with increasing doses, or if blood pressure remains more than 20/10 mmHg too high with only one medicine, a second drug should be added.
ACE inhibitors, like lisinopril, are common first- or second-choice drugs. These drugs lower levels of the hormone angiotensin that tightens blood vessels and increases the heart’s workload. Angiotensin receptor blockers, or ARBs, likewise stop angiotensin by acting at receptors in blood vessel cells. ACE inhibitors are particularly good first choices for patients with diabetes or kidney problems, too. ACE inhibitors and ARBs work similarly, and they share side effects like cough and increased potassium, so they should not be used together.
Other treatment options for hypertension include:
- Beta blockers like albuterol, which help reduce the force and rate of the heartbeat. These drugs also help patients with rapid heart rhythms and unrelated diseases like thyroid or glaucoma conditions.
- Thiazides and other diuretics, like furosemide, which remove sodium and extra fluid from the blood to lower vessel stress. Thiazides are first-choice treatments, especially for African Americans with hypertension; diuretics also help when remove extra fluid in heart failure.
A final established class, the calcium channel blockers (CCBs), lowers the amount of calcium in cells to increase relaxation in the heart and blood vessels. CCBs like amlodipine usually are used when other treatments have not worked. They can be used to treat chest pain but should be avoided with some types of heart failure.
In 2015, a combination drug, Entresto, was approved as a new type of hypertension treatment (an “ARNI”). In addition to the ARB valsartan, Entresto contains sacubitril, a medicine to block stressor substances that tighten blood vessels. Called a neprilysin inhibitor, sacubitril cannot be given with ACE inhibitors because of the increased risk for rare angioedema and death. Combined with an ARB, though, sacubitril reduces symptoms of heart failure and is likely to help lower blood pressure, too. If ARNIs are more effective than the existing safe oral medicines, they could be incorporated into future treatment guidelines.
Choices for lowering different types of high cholesterol
Options to reduce cholesterol in the blood range from niacin, a B vitamin, to new biologic drugs. HMG-CoA inhibitors, called statins, are the most well-known, first-choice cholesterol-lowering drugs. Statins block a chemical that helps make cholesterol in the body and might remove existing cholesterol from the arteries. Statins work very well to protect against heart attack and stroke; although expert recommendations differ, even conservative guidelines suggest use when only one other cardiac risk factor exists. Well-known side effects include muscle pain and mental fogginess, but both are rare and not different from placebo. Patients with diabetes may be more likely to experience muscle problems, though, and there is a small risk of developing diabetes if you take a statin.
Older alternatives act specifically on different parts of the cholesterol molecule:
Niacin, first used in 1955, increases the “good” HDL cholesterol and lowers triglycerides. It works at doses of 1 gram or more per day and typically is used with another drug when triglycerides remain high. Although flushing is possible, it doesn’t represent an allergy and can be avoided in most patients by using lower doses or by slowly increasing the dose.
Fibrates like gemfibrozil or fenofibrate do not affect LDL at all but do lower triglycerides. When combined with statins, they are especially effective for triglyceride (TG) levels greater than 1,000 mg/dL.
The newest option for high cholesterol is not a pill but an injected drug. PCSK9 inhibitors, approved in 2015, block a protein so that more LDL can be taken out of the blood. These drugs—evolocumab and alirocumab—work well to lower LDL even in people with inherited familial hypercholesterolemia (traditionally difficult to treat) or people who don't respond to statins, and they can be used with statins for extra effectiveness. However, insurance rejection rates remain high and prescribing rates, low. As the drug cost decreases and possible effects on stroke or cardiac death rates are better understood, PCSK9 inhibitors could become more commonplace.
A wider arsenal
Blood pressure and cholesterol levels are not the only heart-healthy concerns. To keep the heart in rhythm and pain-free after some damage has already occurred, a variety of other medicines can be prescribed. Drugs like digoxin, aspirin, and nitroglycerin, as well as drugs to slow or steady the heart rate, are important for people with existing heart conditions or heart failure, for example.
The array of effective medicines to protect the heart doesn't mean that lifestyle choices aren't important. And needing medicine despite personal efforts to live the healthiest life you can doesn’t mean that you failed somehow. It just means that your heart needs more than you can give alone. Combining medicine with healthy habits can help both efforts work better. Talk openly with your doctor or pharmacist about your habits and your medicine concerns to keep your heart as healthy as possible.