introduction
Peripheral arterial disease describes diseased arteries outside the heart.
Arteries transport oxygen rich blood from the lungs, via the heart, to the muscles and organs of the body, while veins carry the blood back from the organs to the heart and lungs. In peripheral arterial disease (PAD) the arteries become narrowed or blocked due to fatty deposits on their inner lining. This process is similar to the one that leads to coronary heart disease (CHD) an indeed, people with PAD sometimes also suffer from CAD. PAD can occur in arteries anywhere in the body outside the heart, but most commonly in those of the legs and pelvis.
The narrowing of arteries compromises normal blood flow and causes symptoms which vary with the severity of the disease. The earliest symptoms of PAD include leg pains and cramping associated with physical activity that subside with rest. This characteristic symptom of PAD is called claudication. Severe disease in the legs can cause continuous pain and ulcers due to insufficient blood flow resulting in tissue death (gangrene) and amputation. Over 200,000 surgical and vascular (angioplasty) procedures are performed each year in the United States to prevent the onset of severe tissue damage in PAD.
It is estimated that PAD affects over 10% of the adult population in the industrialized world and one in five over the age of 75. In the United States about eight million people over the age of 40 are thought to have PAD. The condition often goes undetected as the symptoms can be elusive or absent.
Various factors are considered to contribute to the risk of developing of PAD, including environmental factors, of which smoking is considered the most significant. Less is currently known about the impact of genetics although it is generally believed that many genetic variations play a role and that each has a small or modest individual effect on disease development.
Recently scientists at deCODE genetics discovered an association between the diagnosis of PAD and a specific variant in the genome. The variant is located on chromosome 15 within the nicotinic acetylcholine receptor gene cluster. In smokers, this same variant also increases the risk for Nicotine Dependence and Lung Cancer.
The deCODEme Genetic Scan identifies the risk variant rs1051730 on chromosome 15 and provides interpretation of the associated risk for development of PAD in individuals of European descent. Insufficient information is currently available about the association of this variant to PAD in individuals of other ethnicities.
risk factors
Various factors are considered to contribute to the development of PAD, of which the most significant are the following:- Smoking: The single most important risk factor for Peripheral arterial disease is smoking.
- Age and gender: PAD is more common in men than women and the incidence increases with age.
- Other cardiovascular risk factors: In addition to cigarette smoking, diabetes and high blood pressure are significant risk factors. Abnormal cholesterol levels are also associated with PAD.
- Ethnicity: The condition is more common in African-American and Hispanic individuals than those of European or Asian descent .
more information
You can learn more about PAD by talking to your doctor and visiting these websites:
American Heart Association on Peripheral Artery Disease
MedlinePlus on Peripheral Artery Disease
The Society for Vascular Surgery on Peripheral Artery Disease
Vascular Disease Foundation on Peripheral Artery Disease