Sun
19
Apr

Earlier detection of artery disease needed

By Elizabeth Smoots, MD

We give much less attention to our arteries than our hearts. But among my patients I've found that arterial disease is closely related to heart disease. These conditions are equally dangerous and signal widespread atherosclerosis, or hardening of the arteries.

Now, new research indicates that peripheral artery disease (PAD) has largely been unrecognized, ignored, or mistakenly thought to be part of the aging process. Men are particularly at risk for the problem. The good news, researchers say, is that increased use of a simple test in the doctor's office could improve detection of this deadly disorder.

Dangers of peripheral artery disease

A buildup of fatty material in the arteries of the legs, called PAD, is associated with a high rate of cardiovascular disease. According to recent studies, patients with PAD have a risk of heart attack or stroke that is five to seven times greater than the general population—about the same risk as someone who has heart disease.

People with arterial plaque in their extremities can also develop life-threatening problems such as ulcers or gangrene. More than one-third of patients with these complications eventually have a limb amputation.

Who is at risk for PAD?

Many people are not aware of the dangers of clogged arteries in the legs. According to a recent survey by the National Coalition on Aging, only 32 percent of people 50 and older are familiar with PAD. Yet the condition is very common, affecting up to 12 million people in the U.S.

Of those afflicted with PAD, there are about twice as many men as women. The condition increases with age in the general population as follows:
Age (years)Proportion affected (%)
40-592.5
60-698.3
70-7918.8
The other risk factors for PAD are similar to those that increase your chances of getting heart disease. These may include:
  • High blood pressure
  • Abnormal cholesterol
  • Diabetes
  • Obesity
  • Smoking
  • Elevated blood levels of homocysteine
  • Personal or family history of heart disease, stroke, or other cardiovascular disease

Symptoms and signs of PAD

So how do you know if you have PAD? The problem is that early in the disease most people don't have any symptoms. Even later on, only about one-third have classic symptoms of PAD.

The condition's earliest and most characteristic symptom is pain in the calves or thighs while walking, called intermittent claudication. This usually occurs after walking a certain distance, and ends after resting for a consistent length of time. Other symptoms may include:
  • Numbness, weakness, or a feeling of heaviness in the legs
  • Burning or aching in the feet at rest, especially while lying flat
  • Coolness or color changes of the legs or feet
  • Foot sores that are slow to heal

Diagnosis and early detection

Since the symptoms of PAD are often absent or unrecognized, many people who have the disease don't even know it. But a recent study in the Journal of the American Medical Association (JAMA) found that a simple, non-invasive blood pressure test can be done in the doctor's office to detect PAD.

Called the ankle-brachial index, or ABI, the test involves taking pressures in both arms and ankles using a blood pressure cuff and a simple device to detect blood flow called a Doppler. The resulting blood pressure readings are then used to calculate your ABI. A value less than or equal to 0.9 signals PAD.

Researchers in the JAMA study who used the ABI test detected PAD in 29% of 7,000 subjects over the age of 49 who were at risk for the disorder. Over half of these patients had never before been diagnosed with the condition. Of those previously diagnosed with PAD, the patient's current doctor didn't know about it in roughly half the cases. The researchers concluded that PAD is an under-diagnosed condition and that increased use of the ABI test could improve detection.

Who should be screened for PAD?

Everyone who is middle-aged or older should have the pulses in their ankles and feet checked during a routine physical exam. If the pulses are weak, your provider may suggest an ABI or other testing. Many experts also recommend testing for people with risk factors for PAD even in the absence of symptoms.

In my opinion, the best time to diagnose peripheral artery disease is early—preferably before symptoms start. This is when treatment has the best chance of slowing progression and preventing complications.