Peripheral Arterial Disease (PAD) – Diagnostic Criteria and Management
Q: Hello Doctor, I am writing this on behalf of my father. He is Mr. S.P. Pruthi, 56 years old male, suffering from diabetes. His BP is normal, and these days he is having pain in his toes. Sometimes he feels as if they are paralyzed., His legs are getting thinner. His cholesterol level is high and he is a regular smoker. How should I start his treatment to get him fit?
– By Ashish
Your father is most likely suffering from Peripheral arterial disease (PAD) in his legs. This occurs when blood vessels in the legs are narrowed or blocked by plaque formation (fatty deposits) and hence the blood flow to feet and legs decreases.
PAD is also known as peripheral vascular disease (PVD), leg atherosclerosis, or simply poor circulation.
My diagnosis is based on the following points which give a picture of reduced circulation of blood in the legs –
- Pain in his toes
- His legs are getting thinner
- History of diabetes
- History of smoking
- High cholesterol levels
Classical Symptoms of PAD
- Pain, which can occur in the legs, feet, or toes, and often interrupts sleep. Pain may also increase with walking; this type of pain is called claudication.
- Another sign is sores on the legs or feet that heal slowly (longer than 8 to 12 weeks) or don’t heal at all.
- Feet may feel cold because of decreased blood flow.
- Decreased hair growth on the legs.
- Weak pulse in the feet.
Anyone can develop PAD, but people with diabetes, especially those with Type 2 diabetes, have a higher risk of developing it. Also PAD increases with smoking.
Relation of Diabetes to Peripheral Vascular Disease
The excess sugar in the blood damages the blood vessel walls, making them thicker and less elastic. These changes contribute to atherosclerosis (hardening of the arteries). If cholesterol levels are high in blood, fatty plaque start developing on the walls of the arteries. This narrows the lumen of vessels causing PVD in the legs.
Stiff and narrowed arteries reduce the flow of blood and oxygen to leg muscles. This leads to pain in legs.
Diabetes may also damage the nerves of the legs causing peripheral neuropathy. This may induce symptoms like numbness and tingling of feet.
Smoking and Leg Atherosclerosis
The chemicals in cigarette smoke trigger changes in blood vessels that increase the risk of peripheral vascular disease, including:
- Causes damage and creates inflammation in the artery walls, encouraging the build-up of fatty plaque (atherosclerosis) that narrows the arteries and blocks blood flow. Smoking can also trigger these fatty plaques to burst, blocking an artery and causing a heart attack or stroke.
- Stiffens the artery walls making them less able to expand and relax. This affects all the arteries of the body.
- Makes the blood thicker and more likely to form clots.
- Nicotine signals the body to release chemicals that raise blood pressure.
In addition to these direct effects, smokers are less likely to have heart-healthy diets and tend to drink more alcohol. Smokers also have higher levels of LDL (bad) cholesterol and triglycerides, and lower levels of HDL (good) cholesterol. It may independently lead to an arterial disease called Berger’s disease.
Diagnosis of PAD
The ABI (Ankle-brachial index test) is diagnostic of PAD. It is painless and noninvasive, and takes about 20–30 minutes to perform. The patient is asked to lie down for about 10 minutes so that the effect of gravity is the same on your arms and legs; this is necessary to get accurate results. Then the doctor will measure the blood pressure in his arms and in two places on each foot with a handheld device called a Doppler probe. The Doppler probe uses sound waves to detect blood flow. Only the systolic blood pressure (the “top number”) will be recorded for each site. The blood pressure in the patients’ ankles will be compared to the blood pressure in his arms. If it is lower in the ankles than in the arms, he may have PAD.
The diagnostic criteria for PAD based on the ABI are interpreted as follows:
Normal if 0.91-1.30
Mild obstruction if 0.70-0.90
Moderate obstruction if 0.40-0.69
Severe obstruction if < 0.40
Poorly compressible if > 1.30
Further investigations like ultrasound of leg can be done.
Management of Peripheral Arterial Disease
This is very essential. As you can understand, if a person has PAD, he may also have clogged blood vessels in his heart or brain, putting him at higher risk for heart attack or stroke. So it is advisable to start with all preventive measures at the earliest.
With the help and careful monitoring by your doctor, do the following:
- Quit smoking
- Eat healthier. Avoid fried fatty stuff. Include fresh fruits and vegetables in your diet.
- Get more exercises, but do not exert. Exercises are not to be done in a state of pain.
- Control your blood sugar
- Blood pressure and cholesterol levels are to be kept in check.
- Ask your doctor about taking a daily aspirin to prevent clots, or drugs to reduce cholesterol levels.
If a severe blockage is found on investigations, further intervention is required. Either a minimally invasive procedure like an angioplasty that opens blockages with a tiny balloon can be done or bypass surgery to place a new graft to carry blood into the blocked area would be required.
The ABC of Diabetes Management
There are three major treatment goals to keep diabetes under control. This is called the ABCs of diabetes management. Following them lowers the risk of having complications of diabetes, including PAD. Ask your doctor what your individual goals should be and what you need to do to reach them. The closer your numbers are to your goals, the better it is.
- A is for A1C test (short for hemoglobin A1C). This simple blood test that measures your average blood sugar over the last 3 months. It is done at least twice a year. Aim to have an A1C level less than 7%.
- B is for blood pressure. Aim for a blood pressure less than 130/80.
- C is for cholesterol. Aim to have your LDL cholesterol less than 100 mg/dL. Have your cholesterol checked at least once a year.