News Review From Harvard Medical School -- Drug May Reduce Leg Pain, Boost Walking
A common blood pressure medicine may also help people with leg pain from clogged arteries, a new study suggests. The study included 212 people with peripheral artery disease. People with this condition have plaque inside the arteries in the legs. This narrows the channel where blood flows. A common symptom is pain in the legs while walking. People were randomly assigned to receive either ramipril or a placebo (fake pills). Ramipril is a type of blood pressure medicine called an ACE inhibitor. These drugs lower blood pressure partly by making blood vessels wider. People were given a treadmill test at the start of the study. After taking ramipril for 6 months, people were able to walk more than 4 minutes longer. There was little change (about 21 seconds) for those taking the placebo. Those in the ramipril group also could walk without pain for about 75 seconds longer than those in the placebo group. The Journal of the American Medical Association published the study. HealthDay News wrote about it February 5.
By Reena L. Pande, M.D.
Harvard Medical School
What Is the Doctor's Reaction?
Too few people know about a condition called peripheral artery disease, or PAD. In PAD, the blood vessels in the legs become blocked with cholesterol and plaque buildup. These blood vessels normally supply oxygen and nutrients to the leg muscles. PAD affects more than 7 million adults in the United States alone.
The major factors that increase the risk of developing PAD are similar to those that lead to blockages in the heart. They include:
- Smoking
- Diabetes
- High blood pressure
- High cholesterol
When the leg blood supply becomes blocked, people may have pain or discomfort in the leg muscles when they walk. This is similar to the way that people with blockages in the arteries around the heart feel chest pain when they exert themselves.
PAD can have a major impact on quality of life. Besides leg pain, it can cause ulcers or sores that may require leg amputation.
Unfortunately, treatments to improve the leg muscle pain that comes with peripheral artery disease are limited. However, a new research study suggests that drugs called ACE inhibitors may help. These drugs are often used to treat high blood pressure.
Researchers from Australia studied 212 patients with PAD and leg pain for 24 weeks. The study showed significant benefits for people who received the drug, called ramipril.
- They could walk farther overall.
- They walked farther before they first felt discomfort.
- They had better physical function and quality of life.
What Changes Can I Make Now?
A few treatments for leg symptoms of PAD have been proven to work. They include:
- Exercise training -- Exercise is by far the best treatment for PAD symptoms, short of getting more blood flow to the leg (see below). I recommend that my patients walk at least 3 to 5 times per week for about 45 minutes. It's best to walk until it hurts, stop and recover, then walk again. Repeat this pattern until the full time is completed. Many people worry that they will make their legs worse by walking because it hurts to walk. However, research shows that, if you walk regularly, you can more than double the distance you can walk before you have to stop for leg pain.
- Prescription medicines -- The best medicine available is cilostazol (Pletal). This drug can improve walking distance by about half. Pentoxifylline (Trental) is also approved for use but is less effective.
- Restoring blood flow -- This can be done with bypass surgery, which uses your own vein to bypass the blockage and create a new channel of blood to the leg. Another way to restore blood flow is by opening up the blood vessel from the inside with an inflated balloon. Then a wire mesh tube called a stent is used to hold the vessel open. These procedures are recommended only for people with severe symptoms that limit daily function or those with foot ulcers or sores caused by too little blood flow.
How do you find out if you have PAD? Talk to your doctor and describe your symptoms. Your doctor can do a simple test called the ankle-brachial index. This test compares the blood pressure in the ankle to the blood pressure in the arm. If there is a blockage anywhere along the way, the blood pressure at the ankle will be low compared with the arm. A value of less than 0.90 is considered abnormal.
The body's plumbing is all connected. So having blockages in one part of the body can also be a sign of blockages in other important parts of the body, such as the heart or the brain. Having PAD means you are at higher risk of having heart disease or a stroke. This means that it's very important to not only treat the leg symptoms, but also reduce your risk of heart attack and stroke. You can reduce your risk by controlling blood pressure, cholesterol and diabetes, and quitting smoking.
What Can I Expect Looking to the Future?
PAD has not been recognized or treated often enough. This new research is very encouraging. It suggests that a new class of drugs may help people with PAD walk farther and with less pain. More research needs to be done to confirm this study, but it's certainly a start.
Many others are working on new treatments for PAD and trying to understand other reasons that people with PAD get leg discomfort. So far, good treatments for this disease are sorely lacking. I hope that this work will lead to newer and better ones.
