Diabetes Complications - Peripheral Artery Occlusive Disease (PAOD)
Diabetes Complications - Peripheral Artery Occlusive Disease (PAOD)
also known as Peripheral Vascular Disease (PVD) and Peripheral Arterial Disease (PAD)
By Lahle Wolfe

Peripheral artery occlusive disease (PAOD is also known as peripheral vascular disease [PVD]) is a term for all disease caused by the obstruction of large peripheral arteries, which can result from atherosclerosis, inflammatory processes leading to stenosis, an embolism or thrombus formation. It causes either acute or chronic ischemia. It can also effect the lymph vessels.

What is Peripheral Artery Disease (PAD)?

PAD, is a disease of the blood vessels. The arteries supplying blood to the limbs get blocked and usually affects one or both legs but it can also affect the arms or "peripheral" body organs (that is, any organ other than the brain, the heart, or the lungs).

Atherosclerosis, the thickening of the walls of the arteries due to cholesterol-filled plaques, is usually the cause of PAD. Occasionally, PAD occurs suddenly when a blood clot formed in the heart or in another blood vessel breaks off and wedges itself in a smaller artery.

Signs and Symptoms

Many people do not know that they have a problem. They may think that they only have back or muscle pain-related problems, when in fact, they could have PAD. The most common symptom is cramping, pain or tiredness in the leg or hip muscles while walking or climbing stairs. Typically, this pain goes away with rest and returns when you walk again. Other symptoms include:

* Muscle pain in buttocks, calf, leg, or back
* Slight pain or tingling in legs
* Pain that worsens with movement and exercise
* Foot or leg pain at rest

Approximately 75% of all persons with PAD do not have any symptoms; those that do usually mistake them for something else. PAD affects both men and women but men are more likely to experience symptoms than women.

Risk Factors

If you have diabetes, you are at risk for developing PAD. Other risk factors include:

* Cigarette smoking (major risk factor for PAD; smokers who develop PAD are diagnosed about 10 years earlier than nonsmokers)
* Obesity
* Diabetes mellitus
* High blood pressure
* Physical inactivity (exercise increases the distance that individuals with PAD can walk without pain and also helps to decrease the risk of heart attack or stroke. Note: supervised exercise programs are one of the treatments for PAD patients.) High blood cholesterol (LDL)
* Family history of vascular or heart disease
* Age (being over age 50 increases risk of developing PAD)

Stage Classification

Peripheral artery occlusive disease is commonly divided into (Fontaine) stages:

* I: mild pain on walking ("claudication")
* II: severe pain on walking relatively shorter distances (intermittent claudication)
* III: pain while resting
* IV: loss of sensation to the lower part of the extremity
* V: tissue loss (gangrene)

Causes

All causes of atherosclerosis are also causes of PAOD. There is, however, a strong preponderance of diabetic people who smoke. A known diabetic who smokes runs an approximately 30% risk of amputation within 5 years.

Diagnosis

Upon suspicion of PAOD, the first-line test is the Ankle brachial pressure index (ABPI/ABI) which is a measure of the fall in blood pressure in the arteries supplying the legs. A reduced ABPI (less than 0.9) is consistent with PAOD. Values of ABPI below 0.8 indicate moderate disease and below 0.5 severe disease.

The next step is generally a form of angiography, where a catheter is used to inject radiodense contrast agent into the femoral artery and selectively guided to the artery in question. Stenosis of the arteries can be identified, and generally correlates with the patient's symptoms.

Treatment

Dependent on the severity of the disease, the following steps can be taken:

* Conservative measures include Smoking cessation (cigarettes promote PAOD and are a risk factor for cardiovascular disease). Regular exercise for those with claudication helps open up alternative small vessels (collateral flow) and the limitation in walking often improves. Medication with aspirin and statins, which reduce clot formation and cholesterol levels, respectively can help with disease progression and address the other cardiovascular risks that the patient is likely to have.

* Angioplasty(PTA or percutaneous transluminal angioplasty) can be done on solitary lesions in large arteries, such as the femoral artery.

* Occasionally, bypass grafting is needed to circumvent a seriously stenosed area of the arterial vasculature. Generally, the saphenous vein is used, although artificial (Gore-Tex) material is often used for large tracts when the veins are of lesser quality.

* Rarely, sympathectomy is used - removing the nerves that make arteries contract, effectively leading to vasodilatation.

* When gangrene of toes has set in, amputation is often a last resort to stop infected dying tissues from causing septicemia.

Arterial thrombosis or embolism has a dismal prognosis, but is occasionally treated successfully with thrombolysis.

Complications

When the parts of the body fed no longer being by the blocked blood vessels organs and tissues don't get enough oxygen and nutrients. This causes damage and tissues ad organs can die if blood flow doesn't improve. Without treatment a person could lose a leg or die.

PAD can lead to gangrene (tissue death) and amputation, something diabetes may also be at increased risk for without PAD. It is therefore, very important to follow your doctor's instructions on managing blood glucose, diet, and exercise.
Disorders Associated with PAD

Many PAOD patients also have angina pectoris or have had myocardial infarction. There is also an increased risk for stroke.

Diabetes and PAD

Diabetes itself is a risk factor for PAD. Hyperglycemia (high blood glucose levels) is a major contributing factor to many complications of diabetes. A healthy diet, exercise, and stress management care plan all will help you to better control your blood glucose levels and reduce your risk of developing PAD or other complications.

Know your target and ranges for your blood glucose. If you are insure, ask your doctor to write it down for you. Staying in those ranges is one of the most important aspects of diabetes daily care.

Sources

Peripheral arterial occlusion

Merk Manual: Peripheral arterial occlusion

American Heart Association

Wikipedia.com, Peripheral Atery Occlusive Disease, was used as basis for this article; edited for content.

WebMD.com, Peripheral Aterial Disease of the Legs