Dr. Billy Kim, a Vascular Surgeon with The Surgical Clinic, treats patients with Peripheral Arterial Disease (PAD). People with PAD normally experience some sort of pain in their legs. Sometimes this pain occurs while at rest and sometimes it is experienced during times of activity. Understanding your risk factors for PAD can help patients change some aspects of the disease process.
What are the Risk Factors for PAD?
There are several risk factors associated with PAD. These risk factors can be separated into two categories, which are those which cannot be modified, such as age, and those which can be, such as smoking, diabetes, and hypertension. Several large population studies demonstrate that the incidence of painful conditions such as Intermittent Claudication (IC) and Critical Limb Ischemia (CLI) increases with age. No real surprise there.
Smoking and PAD
Smoking has been shown to be an independent risk factor for the development of PAD. There is a two-to-six-fold increase in the risk of developing PAD. In fact, the association of smoking with PAD is thought to be stronger than its association with coronary artery disease. The severity of PAD appears also to be directly proportional to the number of cigarettes smoked in one’s lifetime. The good news is that when someone stops smoking the incidence of conditions like IC decreases.
Diabetes mellitus is associate with a twofold increase in the risk of developing PAD. The risk is directly proportional to the severity and duration of diabetes. For every 1% increase in hemoglobin A1C, a corresponding 26% increase has been suggested in the risk of developing PAD. The other issue with diabetes is poor wound healing in addition to peripheral neuropathy. Therefore it does carry a five to tenfold increase in the rate of major amputations compared to non-diabetics. With this understanding, it is paramount to have a good control of the hemoglobin A1C, thorough evaluation of the feet on a daily basis, especially those with peripheral neuropathy.
Elevated total serum cholesterol, low-density lipoprotein (LDL) cholesterol, decreased high-density lipoprotein (HDL), and hypertriglyceridemia have been associated with an increased risk of developing PAD. This risk is increased by 5% to 10% for every 10 mg/dl rise in total cholesterol. The best predictor for PAD was the ratio of total to HDL cholesterol. In addition, smoking also seems to enhance the effects of hypercholesterolemia.
Low serum HDL levels may also be related to smoking and reduced physical activity. Therefore evidence suggests that control of serum cholesterol and triglyceride levels decrease both the incidence and the progression of PAD. Recommendations include aggressive treatment of these patients with lipid lowering drugs (statins), which is also true for patients with coronary artery disease.
Hypertension is associated with an increased risk of developing PAD. However, this association is weaker than for cerebrovascular and coronary disease. In addition, hypertension risk factor is less when compared to smoking and diabetes.
Additional Risk Factors
Something that is not talked about a great deal is hyperhomocysteinemia. Increased levels of homocysteine levels are detected in approximately 30-40% of patients with lower extremity PAD. This association between hyperhomocysteinemia and PAD has been suggested to be stronger than for coronary artery disease.
Patients with PAD are not only at risk for progression of disease but also for other significant cardiovascular events such as myocardial infarction (20-60% increased) and stroke (40%). Interestingly enough though, the clinical course for PAD in regards to the legs is fairly stable. Only a quarter of patients with intermittent claudication will ever deteriorate significantly. This is attributed to the development of collaterals, metabolic adaption of ischemic muscle, and the alternation of gait to favor nonischemic muscle groups. Therefore a worsening ankle-brachial index (ABI) is the best predictor for deterioration of PAD.
For patients with CLI, 60-90% require some form of a revascularization procedure. These patients generally have a poor prognosis. At 1 year, only 25% of these patients have resolution of their symptoms, 20% continue to have symptoms, 30% have undergone an amputation, and 25% are dead. In those patients who have unreconstructable disease or attempts at reconstruction have failed, the 6 month follow up results indicated that approximately 40% end up with an amputation and 20% die.
Traditional treatment goals for intermittent claudication are to relieve symptoms of pain while walking, to increase walking capacity, and to improve quality of life. The approach for these patients involves a multi-faceted approach to address the risk factors, pharmacologic agents (antiplatelet agents, phosphodiesterase inhibitor, statins) and invasive procedures. These invasive procedures include endovascular interventions such as angioplasty, stent, atherectomy, and combination. More invasive procedures would include endarterectomy, thrombectomy, and bypass.
Recovery from an invasive surgery like a peripheral artery bypass happens in two stages. First, the patient will have to spend 1 to 2 nights in the hospital before being discharged. The patient’s doctor will then give particular instructions that the patient will have to follow at home. Usually, these instructions include exercises to promote healthy blood flow.
In order to avoid placing strain on the veins, patients should avoid sitting for long periods of time while in recovery. Driving should be avoided until the doctor recognizes enough progress has been made. Patients can expect 6 to 8 weeks until full recovery.
If you need surgery for peripheral artery disease, practicing good exercise and diet habits will help you prepare for surgery. Talk with your doctor or surgeon for more recommendations about preparing for treatment.
Specialized Treatment at The Surgical Clinic in Nashville, TN
At The Surgical Clinic, PLLC, board-certified vascular surgeons are trained and equipped to assess, identify and provide various treatment options for our patients. This may include conservative risk and behavior modifications, pharmacologic agents. Depending on the severity of IC and CLI, the next steps may include invasive interventions which we will provide the full spectrum of treatment tailored to the needs of the patients.