Description

• Reproducible, exercise-induced cramping pain in a defined group of muscles that is relieved by rest
• May also be asymptomatic or present with atypical signs, such as trouble walking, leg fatigue, or leg pain
• Most patients with peripheral arterial disease (PAD) have atherosclerotic disease of the lower extremity and therefore compromised blood flow most commonly felt in the calves, but it also can affect the feet, thighs, hips, and/or buttocks.
• 10–35% of patients with PAD report classic claudication symptoms.

Epidemiology

• Strongly associated with smoking and diabetes mellitus
• Predominant sex: Male > Female (<2:1 ratio)
• Increases progressively with age (estimated 6% in those age >70 years)

• Incidence is related to age: 0.07% of men 35–44 years of age and 1.4% of men age >65 years develop the disease per year.
• Diabetic patients have an incidence >4–6× that of nondiabetic patients.

• 2–3% of men >60 years of age have symptomatic PAD compared with 1–2% of women of the same age.
• Noninvasive testing shows that the true prevalence of PAD is at least 5× higher than the reported prevalence of intermittent claudication.

Risk Factors

• Cigarette smoking: 90% of all patients with claudication
• Diabetes mellitus
• Hypertension
• Hyperlipidemia
• Family history
• Pre-existing heart disease (15% of patients with congestive heart disease [CHD] have vascular disease in other beds)
• Advanced age

General Prevention

In general, reduce cardiovascular risk:

• Frequent walking exercises
• Smoking cessation
• Control of BP, lipids, and glucose levels

Pathophysiology

• Atherosclerotic stenosis/occlusion of arterial flow diminishes BP to the muscles of an extremity.
• Symptoms generally are exacerbated by exercise when blood flow demand exceeds supply distal to the area of stenosis/occlusion and reduces tissue perfusion.

Etiology

• Usually defined by clinical history (e.g., history of atherosclerosis, migraines, vasculitis, radiation exposure, limb trauma)
• Sites affected depend on the area of arterial supply involved: Symptoms occur distal to the area of arterial stenosis/occlusion.
• Superficial-femoral artery: Most common area associated with claudication; pain in the upper 2/3 of the calf
• Aortoiliac disease: Pain may extend from buttock to thigh (if impotence also is present, consider Leriche syndrome)
• Aortoiliac or common femoral artery: Pain in the thigh
• Popliteal artery: Pain in lower ⅓ of calf
• Tibial or peroneal artery: Pain in the feet (if isolated foot claudication, consider thromboangiitis obliterans)
• Subclavian, axillary, and brachial disease: Pain may extend to the upper extremities.

Commonly Associated Conditions

• Other manifestations of atherosclerosis:
  • Myocardial infarction
  • Carotid artery occlusive disease
  • Renovascular occlusive disease
  • Hypertension
• Of all patients with PAD, 25–68% have concurrent coronary artery disease and 34–50% have a concomitant cerebrovascular disease.