In the past, patients and physicians have considered intermittent leg pain as a natural part of the aging process. It is now known that the intermittent pain is a symptom of a potentially serious disease known as peripheral artery disease (PAD). PAD occurs when there is a buildup of fatty deposits in the inner lining of the artery walls. This buildup, known as atherosclerosis, causes the artery to become narrowed and thus limits the blood supply to the leg muscles. In advanced PAD, the blood flow to the leg muscles can become so low that pain occurs even when at rest. This is a sign of severe PAD and possibly critical limb ischemia.
The term peripheral artery disease (PAD) describes a condition where atherosclerosis has occurred in the blood vessels that provide blood to the extremities – the legs, feet, arms, and hands. The atherosclerosis causes the blood vessels to narrow and can often result in the decreased delivery of oxygen and vital nutrients to the extremities. However, it is still possible for significant narrowing to occur without the development of symptoms. This insufficient blood delivery can result in damage to the tissue and the development of symptoms.
What is Peripheral Arterial Disease?
It is crucial to understand what Peripheral Arterial Disease (PAD) is in order to identify the early warning signs. PAD involves the build up of plaque in the arteries that lead to the extremities. The condition can be generalized to all arteries but more commonly affects the arteries of the legs. Plaque build up occurs when the lining of the artery is damaged by high blood pressure, high cholesterol, smoking or high blood sugar. When the lining is damaged, fat deposits in the damaged area of the lining. It is the body’s attempt to ‘patch’ the damaged area. Over time, the fat and other blood components harden and stick to the artery wall. Overtime, the build up narrows the artery and limits blood flow to the affected area. This process is also a good indication of how coronary artery disease occurs. It is just that PAD is isolated to the lower extremities. This is why people with PAD are at a higher risk of heart attack and stroke.
Importance of Identifying Early Warning Signs
Early identification of PAD alerts the health professional to the patient who is at risk for developing critical limb ischemia (CLI), which, as the terminology suggests, represents a severe deep funk with a possibility of tissue loss. Patients with CLI represent a subgroup of sufferers whose hazard of cardiovascular-related loss is many times that of age-matched controls and who have a high risk of limb amputation within 6 months of presentation. Identification of those patients who are at risk for developing CLI is a crucial challenge; although all patients with PAD are at risk, those with classical symptoms of intermittent claudication have a lower risk than individuals with atypical leg symptoms, such as heaviness and discomfort on foot elevation, who are at higher risk than those with rest pain. An easy, valid, and reliable way of identifying those patients at greatest risk for progression to limb-threatening ischemia will facilitate studies aimed at prevention and allow optimal targeting of aggressive cardiovascular risk factor intervention and the use of adjunctive medical therapies. Considering the projected exponential growth in PAD prevalence over the following 2 decades, there is an urgent need for improvement in both basic and clinical methods to identify and treat those at risk for limb loss.
Risk Factors for Peripheral Arterial Disease
Age is perhaps the most significant non-modifiable factor, with a prevalence of 15% noted in people over 70 years of age and increases to 20% in those over 75 years. It is also much more prevalent in men than women, with the prevalence being 3-4 times higher. The risk factors often tie in together, and diabetics generally suffer a more severe form due to acceleration of the atherosclerotic process. Cessation of smoking and control of sugar levels has been shown to help manage PAD. High blood pressure has a linear relationship with the risk of PAD. A recent meta-analysis showed that the risk of PAD with hypertension was increased by 2.5 times. The INTERHEART study from the Lancet showed an association of increased cholesterol/HDL ratio with many of the 11,000 patients having suffered an acute myocardial infarction, and the increased ratio was also independently associated with PAD. Again, smoking and abnormal lipoprotein metabolism often tie with diabetes, with it being driven by obesity, making it a multifactorial risk. Around 90% of patients with intermittent claudication have an abnormality of lipoprotein, usually high cholesterol. The effect of obesity is shown to be a greater increase in the risk of PAD in women compared to men. An increase of 3.3 times in women with PAD compared to those without it was shown with a body mass index of 31-36. This can often impair mobility and damage the leg arteries due to the increased systemic inflammation and lipid deposition. However, although the association between each condition and PAD is significant, none of these individual states have the same relative risk as current cigarette smoking. In fact, some states are only deemed ‘weakly related’. High cholesterol showed an increase of 2.2 times for the development of PAD in those with levels of over 240mg/dL compared to those with levels under 190. 2.7 times the risk was shown for hypertensive smokers compared to non-smokers with a normotensive blood pressure. The classic symptom of intermittent claudication in the legs has a prevalence of 6% in men and women aged between 45-74 years, again increasing with age. With the increase of life expectancy and early mortality in diagnoses such as acute myocardial infarction and stroke, it is only likely that the interest in PAD will increase. An interesting consideration from research from the Framingham study is that identified gender differences shown in a shift of conventional risk factor to attributing PAD in women with specific risk. This risk was a higher platelet count showing a 2.3 times future risk of intermittent claudication, and the use of postmenopausal hormone therapy with it again showing a relatively increased risk.
Age and Gender
Elderly individuals with PAD have high rates of functional impairment, which can have profound implications on disability and quality of life. In general, rates of intermittent claudication and its associated functional limitation are about 2 to 3 times higher in men compared to women. However, elderly women with PAD appear to have a higher prevalence of atypical leg symptoms, such as exertional leg pain, numbness, or weakness. In the absence of traditional symptoms, it is likely that PAD is under-diagnosed in this group. Atypical leg symptoms are associated with impaired functional status, and a decline in functional status has been shown to be a strong independent predictor of subsequent cardiovascular events and mortality in patients with PAD.
A recent study examining sex differences in the population-attributable risk of various cardiovascular disease factors found that the higher prevalence of smoking, diabetes, and hypertension in men compared to women accounted for most of the increased cardiovascular risk in men. This would suggest that sex itself does not confer higher risk for PAD, but that modifiable risk factors are what drive the higher prevalence of PAD in men. Regardless, it is evident that age and male sex are strong non-modifiable risk factors for PAD. This is an important consideration given the projected increase in the elderly population in the upcoming decades. With the aging of the baby boomer generation, it is expected that the number of adults with PAD will increase dramatically unless specific efforts are made to reduce incidence of the disease. An understanding of the anticipated growth in the prevalence of PAD has important public health implications in that it may serve as a stimulus to policymakers to put into place programs aimed at PAD prevention and management.
The risk of PAD is significantly higher in the elderly population and is known to affect men and women disproportionately. Prevalence of PAD increased with each decade of life among both men and women, from 1% for those 40 to 49 years of age to over 20% for those 70 to 74 years of age. Men have a notably higher prevalence of PAD compared to women, especially in the younger elderly; however, this difference essentially disappears at older ages. Whether sex has independent effects on the risk of PAD has been a topic of much debate.
Smoking and Tobacco Use
Tobacco has been recognized as a major correlation to the onset of Peripheral Arterial Disease. The chemicals in all forms of tobacco, including cigarettes, pipe tobacco, cigars, and chewing tobacco, have been proven to cause significant damage to the blood vessels. When compared to nonsmokers, those who smoke and use other forms of tobacco have about three times the risk of developing peripheral arterial disease. Time and time again, research has proven that the most effective way to reduce the risk of developing PAD is to quit smoking, or not to start if you don’t smoke already. Focuses on prevention by promoting programs and treatments that will encourage potential and current tobacco users to stop. Heavily funded by the National Heart Lung and Blood Institute, and using statistical information from clinical trials and studies, it has been widely successful in reducing the amount of tobacco use in America. Pooled data from the HIP and CLIPS trials were analyzed to determine the effects of smoking cessation and the use of various pharmacotherapies on PAD incidence. What they found was that participants who continuously abstained from smoking had a 74% lower incidence of peripheral arterial disease, and an 81% reduction in intermittent claudication. This tells us and future generations of tobacco users that using pharmacotherapies and cessation techniques to quit smoking will significantly reduce the onset of PAD and its symptoms in the long run.
High Blood Pressure and Cholesterol
Also, as age increases, older persons are more likely to have high blood pressure because high blood pressure begins to increase after age 35 up until age 60. For those 60 and older, it is most common in women and in men. We could not explain why it is more common in the different sexes. High blood pressure is more common in lower income groups than in those with a higher income. An effort to prevent the development of high blood pressure and to effectively treat it will help to reduce the incidence of P.A.D. Knowing that socioeconomic status and education also play a role with high blood pressure and P.A.D., with the correct knowledge, there can be prevention of P.A.D in the earlier stages of developing it. High cholesterol has been associated with atherosclerosis in many studies. Development of a limp or pain while walking (caused by many things) could be a symptom of Peripheral Arterial Disease. Previous heart disease or cerebrovascular disease or a marked increase in symptoms can also be important findings. This page will describe the causes of P.A.D, its early and late symptoms, who is at risk for developing it, how it is diagnosed, what is involved with the treatment, and how it can affect a person’s lifestyle. The most important and prevalent cause of P.A.D is atherosclerosis.
Diabetes and Obesity
Obesity is also a risk factor for PAD, although there is limited evidence to show it has a direct impact on PAD. However, the atherogenic risk factors associated with obesity (such as hypertension, diabetes, high cholesterol) are all strong risk factors for PAD. Studies have shown that weight loss and increased physical activity in obese patients can reduce blood pressure, reduce total cholesterol and LDL cholesterol, and increase HDL cholesterol. This would therefore decrease the chances of the patient getting PAD or improve the symptoms of patients who have PAD.
Diabetes is a very influential risk factor for PAD. It is related to atherosclerosis and high blood pressure. These conditions, in conjunction with PAD, can cause serious damage to the arteries, increasing the risk of infection and possibility of amputation. It is estimated that between 20-50% of patients with PAD have diabetes, and they usually have poorer outcomes. The reason for this is that most diabetics have nerve damage, a condition known as neuropathy. Neuropathy impairs sensation in the extremities and can disguise the symptoms of PAD, increasing the risk of infection. Furthermore, unlike patients without diabetes, those with diabetes who undergo surgery for PAD symptoms have a 2-3 times higher risk of heart attack or death during the surgery and a 20-30% higher risk of a serious complication happening after surgery. This is usually a result of the widespread nature of atherosclerosis in diabetic patients. Finally, diabetes increases the risk of intermittent claudication progressing to critical limb ischemia, whereby patients have a combination of severe pain and lack of blood flow to the legs or feet. This is the most serious form of PAD as it increases the risk of amputation and decreases life expectancy.
Family History and Genetics
Genetic markers have also been identified which can determine predisposition to certain risk factors for peripheral arterial disease. Research is ongoing in many aspects as to whether it may one day be possible to screen for those markers, thus determining potential sufferers and taking preventative measures at an early stage.
Family history of heart disease and a person’s family medical history can help to identify potential risk factors for peripheral arterial disease. Specifically, if a person’s father or brother suffered a heart attack before 50 years of age or if a person’s mother or sister suffered one before 60 years of age, that person and their siblings are 50% more likely to develop heart disease and, as such, peripheral arterial disease. The nearer the relative, the greater the risk. For example, if both parents suffered a heart attack before the age limits specified, the risk is between double and four times normal.
Recognizing the Early Warning Signs
Slow healing wounds and chronic sores on the toes, feet, or legs are a common symptom of P.A.D. due to the reduced flow of oxygen-rich blood to the affected area. These sores can develop into open wounds which can become infected, and because of poor healing, the infection can progress and possibly lead to amputation. It is important to treat non-healing wounds with proper medical care to prevent infection.
Changes in skin color can be an indicator of a more advanced case of P.A.D. If the legs or feet become pale during elevation and a dusky red when lowered, this could be a sign of an advanced case of P.A.D. Severe arterial insufficiency can cause the nail beds to have a bluish discoloration. The diminished blood flow can also lead to atrophy of the skin and it may appear shiny.
Leg pain and cramping caused by walking or climbing stairs, that stops after a few minutes of rest, is the most common symptom of Peripheral Arterial Disease (P.A.D.). The reason the pain occurs with activity is because the muscle, during exercise, needs more blood flow, but the diseased arteries are unable to deliver adequate blood. The location of the pain depends on the location of the clogged or narrowed artery. Muscle pain or cramping in the calves, thighs, or buttocks is a common indicator of P.A.D. in the legs.
Leg Pain and Cramping
Warning signs are troubles that indicate arterial insufficiency at its early stages. Intermittent claudication is pain due to muscle ischemia, typically on walking and is relieved by rest. It is an insensitive and nonspecific marker for peripheral arterial disease because many people do not interpret it as pain or stiffness in the legs. They may think they are just getting old or unfit and take little notice of it. Ask specifically about discomfort in the calves, thighs, or buttocks on walking and its relief by resting. Claudication distance can be used as a crude marker for disease severity; however, its value may be limited by other coexisting musculoskeletal conditions, and a too and fro history may be difficult to elicit. It should be differentiated from neurogenic and musculoskeletal pains, which are usually eased by stopping, standing still, or adopting a different posture. The differential diagnosis for leg cramps is broad. Many people get night cramps, which are not vascular in origin. These usually occur in the elderly and can be associated with drug treatments, medical and surgical conditions, or no apparent cause. It is said that cramps due to arterial disease more commonly involve the calf and are also active on walking. However, this is a nonspecific distinction.
Changes in Skin Color and Temperature
While changes in skin color and/or temperature are not as frequent a complaint as some of the other symptoms, they are the ones most commonly associated with arterial problems. The extremities, particularly the lower ones, rely on an efficient blood flow system to maintain the delivery of oxygen and nutrients to the cells, as well as to carry away waste products. Color changes occur in stages – in the early phase, the skin turns pale. This suggests a 50% or more reduction in normal blood flow. If the ischemia is prolonged, the skin then turns a dusky bluish tinge, then dark red or black in the end stages. The skin may also become shiny and thin with hair loss. Temperature of the skin can also give indications of abnormal blood flow. When compared with the other limb, a cooler limb suggests insufficient blood flow, whereas a warm limb may suggest a thrombosis as opposed to a gradual narrowing of the artery. This puts the affected limb at risk of compartment syndrome.
Slow Healing Wounds and Ulcers
PAD is a very serious disease that often goes undiagnosed. Its symptoms of leg pain and cramping, changes in skin color, temperature, slow to non-healing wounds and ulcers, and weak or absent pulses in the legs can all be attributed to other conditions. This can be very dangerous as other conditions may not require the most effective treatment for PAD, which is lifestyle changes, medicine, or in severe cases, angioplasty or surgery. Knowing the symptoms is the first step in preventing PAD from worsening.
If you injure your leg, what do you expect to occur? You assume that with time, the skin will close up and the wound will heal, right? Well, this may not be the case for someone suffering from PAD. Because of the decreased blood flow, injuries as small as scrapes or insect bites can cause open sores called ulcers. Ulcers occur mainly on the sides of the feet or the toes and appear as a hole or sore. They are very painful and can become infected if not treated properly; in severe cases, amputation may be necessary for ulcers that do not heal.
Weak or Absent Pulse in the Legs
The pulse in the feet or legs is usually lower than the pulse in the arms. When there is a lack of blood flow to a specific area of the body, the pulse is weaker or non-existent. Physicians will grade the pulses from 0 to 4, with 0 being no pulse and 4 being a normal pulse. This is similar to the blood pressure grading scale which ranges from 0 (systolic pressure of less than 80) to IV (systolic pressure of more than 220). Any pulse graded under a 2 is considered abnormal. The two kinds of pulses that a physician will check for are arterial pulses and femoral pulses. These pulses can represent the health of the blood vessels in the lower extremities and can help a physician detect early PAD. Any asymmetry in pulses can represent a problem with blood flow on one side of the body. This may be an indicator of a site-specific blockage on the side with the weaker pulse. High thigh and groin area pulses can indicate that a blood flow problem is in its early stages and can still be reversed. This kind of blockage is common in diabetics and could signify worsening diabetes or complicated atherosclerosis.
Erectile Dysfunction in Men
Due to shame or embarrassment about discussing sexual health, men may not address erectile dysfunction with their physician. However, the symptom is a cause for concern and should be evaluated by a doctor, as it may signal a serious underlying health problem. The presence of erectile dysfunction in younger men, as well as smokers of any age with the disease, is a particularly strong predictor of widespread atherosclerosis in other parts of the body.
Erectile dysfunction is an occasional concern for men and is not always due to a medical condition. However, chronic erectile dysfunction that occurs on a regular basis is a possible symptom of peripheral arterial disease. While the link between the two is not entirely known, it is believed that the same process of fatty plaque build up in the arteries associated with a hardening of the arteries known as atherosclerosis that causes peripheral arterial disease may ultimately affect penile arteries.
Seeking Medical Attention and Treatment Options
The importance of early diagnosis cannot be overemphasized. Early identification of the disease and early intervention can significantly improve the patient’s quality of life and functional capacity. It can also help to prevent heart attack, stroke, amputation, and death. Those with symptomatic PAD have a six-fold increase in heart attack and stroke risk. Currently available treatment methods can be highly effective in saving limbs and lives of patients with PAD. Unfortunately, it is all too common for those with PAD to either not report leg symptoms to their physician or for the physician to minimize the importance of leg symptoms. Studies have shown that less than 50% of those with PAD experience leg symptoms report them to their physician. Many individuals and their healthcare providers are unaware of the seriousness of the disease and the effectiveness of treatment. Increasing public and healthcare provider awareness of PAD and its proper treatment is a key strategy in reducing the heavy burden of PAD. This document can be an important educational tool in such efforts.
Importance of Early Diagnosis and Treatment
Early diagnosis and treatment of PAD are aimed at accomplishing two goals. The first is to relieve symptoms and improve walking performance. This is a quality of life issue for people who have trouble walking because of leg pain. The second goal is to modify the natural history of the disease and prevent cardiovascular events. So too with the general approach to treatment, risk factor modification and medical therapy are most useful in achieving these goals.
An important step for both patients and healthcare providers to take, identifying those at risk for PAD and intervening early to prevent overt disease, is to increase awareness about the disease and its risks. This topic is discussed in more detail in section IV, “Community and Population Approaches.”
Without a doubt, the early diagnosis and medical treatment of peripheral arterial disease (PAD) is of utmost importance, believed to possibly prevent many unnecessary deaths and amputations. Early diagnosis enables early treatment to modify the disease and prevent its worst outcomes. Unfortunately, PAD often goes undiagnosed by clinicians. Misunderstandings about the nature of PAD, the underscoring of familiar symptoms such as claudication, and physical inactivity by many patients, and the failure to take a patient’s symptoms seriously all contribute to this lack of diagnosis. Nevertheless, with increased public and healthcare provider awareness of the disease and its risks, early diagnosis of PAD should become increasingly more common.
Medical Evaluation and Diagnostic Tests
Medical evaluation and diagnostic tests are the first step in determining the severity of arterial disease and its impact on blood flow. Tests can also sometimes identify the location of the buildup in your arteries. Often, diagnosis begins with a medical history and a physical exam. During the exam, the healthcare provider will look for weak pulses in the affected leg or the presence of a bruit. A bruit is an abnormal sound of turbulent blood flow that can be heard with a stethoscope. This sound may indicate a narrowing or blockage of the blood vessels. In some cases, your doctor may measure the blood pressure in your ankles and compare it to the blood pressure in your arms using a simple and painless test with blood pressure cuffs (this test is known as the ankle-brachial index). Another useful test measures the Doppler pressure. This test is painless and helps to determine the blood flow in your arteries. The doctor places blood pressure cuffs at various points on your arm and leg while taking blood pressure measurements using a Doppler ultrasound device. This device consists of a handheld instrument that uses sound waves to create images of blood flow on a computer screen. Doppler ultrasound can also be used to provide an image of the artery to determine if there is a specific area of narrowing.
Lifestyle Changes and Self-Care Strategies
Our patient described above was counseled about her high-risk disease status and the potential for future intervention by a cardiologist due to her complaint of claudication. She was also educated on expected improvement and worsening of symptoms through documentation of ABI and subsequent measurement of exercise duration to claudication onset. This was an effective strategy to empower the patient to engage in exercise, increasing PAD symptoms of claudication and further referral for intervention hold high significance in helping this woman to change her health behavior for the better.
– Quick screens, for example, 1 question: American Heart Association Life’s Simple 7 for ideal cardiovascular health. – Health coaching can also be an effective tool. showed through the Heart and Soul Study that distress was common in patients with stable coronary heart disease and was associated with a greater incidence of MACE.
Medications and Surgical Interventions
Patients with peripheral arterial disease usually have other medical problems. The goal is to treat all of these conditions in order to lower the risk of heart disease and stroke. Heart disease is the number one cause of death for PAD patients, thus aggressive treatment of heart disease is very important. However, the most important treatment is still directed at the legs to relieve pain and improve walking distance. Treating high cholesterol has been shown to slow the progression of PAD. A healthy diet, weight control, and exercise are the first steps, but many people will also need cholesterol-lowering medications. Blood pressure control is also very important, and studies have shown that ACE inhibitors and angiotensin receptor blockers such as ramipril and losartan can improve walking distance in patients with PAD. A variety of medications can improve walking distance and relieve leg pain in patients with intermittent claudication. The most effective and best studied drug is cilostazol, which has been shown in multiple trials to increase pain-free walking distance. Cilostazol is a type of medication called a phosphodiesterase inhibitor, and it helps to relax the walls of the blood vessels and decrease inflammation. The other medication that is often used to improve walking distance is pentoxifylline, which helps to decrease the blood’s viscosity and improve red blood cell flexibility. Although not as effective as cilostazol, it is a cheaper alternative with fewer side effects.
