Risk factors for peripheral artery disease pinpointed
Atherosclerosis, the disease process that causes fatty blockages in the heart's blood vessels (a condition known as coronary artery disease) can also cause blockages in the arms and legs, where it is called peripheral artery disease, or PAD. Like coronary artery disease, PAD increases the odds of having a heart attack. It can also cause leg pain when walking and is responsible for many foot and leg amputations. Although the same factors that contribute to coronary artery disease are thought to cause PAD, the impact of the individual factors on PAD has been unknown. A study led by researchers at Harvard-affiliated hospitals used the nearly 45,000 men in the long-term Health Professionals Follow-up Study to determine how individual risk factors are connected to PAD. They identified men who had no evidence of coronary artery disease upon enrollment, and then noted which of them developed significant PAD over the years. They found that type 2 diabetes, high blood pressure, past or current smoking, and high cholesterol were the four factors most closely tied to the development of PAD. The results were published in the Journal of the American Medical Association.
For current smokers, the risk was dose-related, with the heaviest smokers being the most likely to develop PAD. In former smokers, the risk declined along with the length of time since quitting. However, any past smoking greatly increased the chance of developing PAD, with those who had quit more than 20 years earlier still nearly four times more likely to develop PAD than men who never smoked.
For type 2 diabetes and high cholesterol, how long the individual had the disease determined the risk of PAD. This was not the case with high blood pressure, however, which elevated the risk evenly for everyone.