That pain in your calf could be PAD

Most people have heard about the dangers of plaque buildup in the heart’s arteries. But did you know the same problem can occur in your arms or legs?

Called peripheral artery disease, or PAD, it’s a form of atherosclerosis, the broader term for plaque accretion on the lining of your arteries, and the lessening of blood flow that results. The same condition sometimes strikes the coronary arteries in your heart, the carotid arteries in your neck, the femoral arteries in your thighs, or arteries in your abdomen. When it hampers blood circulation in your arms or lower legs, it’s called peripheral artery disease, but it’s all atherosclerosis.

“The number one, two and three causes are smoking, smoking, smoking,” said Harold J. Welch, MD, a vascular surgeon with The Vascular Care Group in Hyannis.

“Ninety-five percent of patients with PAD have smoking history,” he said.

According to the Centers for Disease Control and Prevention (CDC), about 6.5 million Americans over 40 have PAD, with slightly more men than women diagnosed. Risk factors include:

• History of smoking.
• High cholesterol levels.
• Diabetes.
• High blood pressure, also called hypertension.
• Age older than 60.
• Family history of PAD or coronary disease.

Trauma and some medical conditions can also cause PAD, but the vast majority result from years of smoking, Dr. Welch said. Cigarette smoke contains about 300 substances, and some of these irritate arterial linings, setting the stage for cholesterol and other components of plaque to stick to the inside walls of arteries, he said. According to the American Heart Association, smoking tobacco not only fosters new plaque formation, but it promotes more rapid growth of existing plaque deposits. Continuing to smoke after PAD has set in only makes it worse.

For Dr. Welch, the battle against smoking is personal.

“Both of my parents died at age 70 from smoking,” he said. “We’d be out of a job with no tobacco.”

PAD Symptoms

Peripheral artery disease is systemic and incurable, but treatment can relieve symptoms and slow or perhaps halt progress. It’s typically detected when a person complains to their primary care physician of pain in their calf muscle while walking, or foot pain while in bed, Dr. Welch said.

Pain during exercise, called claudication, is caused by lactic acid buildup because clogged arteries aren’t supplying enough oxygen, he said. If a person with PAD has claudication, the pain improves after a break from exertion. Foot pain while lying in bed, called rest pain, happens because gravity isn’t helping push arterial blood into the foot, Dr. Welch explained. It will improve when a person with PAD hangs the leg alongside the bed or sits up.

According to the CDC, other symptoms include:

• Muscle weakness in the affected limb.
• Ulcers or sores that don’t heal.
• Skin on the affected limb that’s smooth and shiny or cool to the touch.
• Pulse in legs is hard to detect or missing.

The CDC also says that 40 percent of people with PAD don’t experience leg pain, but Dr. Welch said he doesn’t treat people who are asymptomatic.

Diagnosis and treatment

When a patient is referred to him for possible PAD, Dr. Welch said he asks about general health and any history of smoking, family history of PAD, as well as other vascular issues, including chest pain or stroke symptoms. He will check pulses in the carotid arteries, femoral arteries in the groin, as well as in the arms and legs.

Two forms of ultrasound may be used to check pulses. The Doppler method compares the sound of pulses on the leg and at the ankle. Duplex ultrasound uses Doppler and also can focus on a specific blood vessel and provide images that can be examined for blockages, Dr. Welch said. Imaging tests with computer tomography (CT or CAT scans) or magnetic resonance (MR) may be done.

Treatment will start with making sure cholesterol levels and any diabetes are being managed. Aspirin and a statin (for lowering cholesterol) may be prescribed. Exercise will be recommended, even if walking causes leg pain. Exercise will gradually improve performance and stimulate so-called collateral vessels to help supply oxygen-carrying arterial blood.

“I tell them to exercise, but it’s going to hurt,” Dr. Welch said. “No pain, no gain. You will improve your walking.”

And patients will be told to stop smoking.

“Most of them will try to quit,” he said. “I’m pretty blunt with them. I’ll ask them, ‘Do you like walking or do you like smoking?’”

Most of his PAD patients are older, and Dr. Welch said he doesn’t expect someone in their 70s to dramatically change their diet to help lower cholesterol.

For patients needing surgical intervention, a catheter can be run into an occluded leg artery where a small balloon at the tip expands to widen the blood vessel. A small stent may then be placed to keep the vessel propped open. This procedure, known as balloon angioplasty, can be done on an outpatient basis at the office.

A second option, a surgical bypass of the blocked area, would be done on an inpatient basis at Cape Cod Hospital. In this procedure, blood is rerouted around the area using a plastic tube or perhaps another blood vessel from the patient. Both procedures also are used to treat atherosclerosis in the heart’s coronary arteries.

“You can improve your symptoms, but it’s not going to make your plaque go away,” Dr. Welch said.

The picture is much more favorable for nonsmoking PAD patients.

“In fact, people who don’t smoke and don’t have diabetes and have pain with claudication, the chance of needing any surgical intervention is about 5 percent,” he said.

PAD trends

The picture of trends for PAD and its risk factors is mixed. Rates of obesity, diabetes and hypertension in the U.S. have all risen in recent years, according to the CDC. On the positive side, cigarette sales declined for the past two decades, though they increased somewhat in 2019, according to the Federal Trade Commission.

“I’m not sure obesity in and of itself is a viable factor” as a cause for PAD, Dr. Welch said.

But obesity is associated with developing diabetes and hypertension, both of which harm your circulatory system and are PAD risk factors. PAD raises your overall risk of stroke or heart attack, as the condition is a local expression of the body-wide problem of atherosclerosis.

A 2021 article in Circulation Research states that the most recent data on prevalence of PAD in America dates to the 1990s and newer information is needed. It also notes that the aging of the U.S. population should be considered as a factor.

“I’d say it’s fairly common on Cape Cod, given the older population down here,” Dr. Welch said.