Vascular Atherosclerotic Risk Prevention in Patients with Peripheral Arterial Disease
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Abstract
Purpose. Peripheral arterial disease (PAD), defined as the presence of atherosclerotic occlusive vascular disease of the extremities, is a marker of systemic atherosclerosis, and has emerged as a strong risk factor for cardiovascular morbidity and mortality. Early diagnosis and aggressive medical therapy can significantly reduce cardiovascular risk profiles in such patients.
Methods. An Ovid and Medline search was used to identify relevant publications pertaining to PAD. Included were randomized, blinded, placebo-controlled studies, current accepted committee reviews, and reviews pertaining to PAD. An analysis of cardiovascular risk stratification and risk reduction in patients with PAD was performed. Current recommended medical treatment options were reviewed in terms of risks, benefits and number needed to treat (NNT) analysis.
Results. Smoking cessation, on average, will prevent 1 cardiovascular mortality for 13.5 patients abstaining for 1 year.19 Treatment of 38 patients with moderate exercise for one year would prevent one cardiovascular death.22 Aspirin therapy will prevent one major cardiovascular event [defined as stroke, myocardial infarction (MI) or cardiovascular death] in 106 patient years; clopidogrel therapy will prevent one major cardiovascular event in 84 patient years;3 ticlopidine therapy for similar time period will prevent 1 major cardiovascular event (defined as stroke, MI or cardiovascular death) in 61 patient years treated;23 angiotensin converting enzyme inhibitors (ACEI) will prevent 1 major cardiovascular event (defined as stroke, MI or cardiovascular death) in 119 patients years;29 HMG-CoA reductase inhibitors have proven beneficial with a decrease in events (defined as all cause mortality, cardiovascular mortality, major coronary events and coronary and non-coronary revascularization) seen with 50–70 patients treated for 1 year, independent of serum lipid levels.27
Conclusion. PAD should be treated with a multi-disciplinary approach, including smoking cessation, exercise and medications. Medical therapy should be comprised of a statin, an antiplatelet agent and/or an ACEI. Perspective trials comparing different combinations of these three pharmacological classes of agents in PAD are warranted.
Introduction
Peripheral arterial disease (PAD), defined as the presence of atherosclerotic occlusive vascular disease of the extremities, is a common yet often under-diagnosed medical condition with a peak incidence in the 6th and 7th decades. PAD affects about 5 million adults in the United States.1 The major risk factors for PAD are cigarette smoking, age > 40, diabetes mellitus, hypertension and hyperlipidemia. Of these, cigarette smoking has the greatest relative risk in patients with PAD. The presence of atherosclerotic disease in the lower extremity vasculature is often indicative of disease in cerebrovascular and coronary arteries. PAD is a proven risk factor for an impending major cardiovascular event.2 Early diagnosis and aggressive treatment of risk factors has been proven to reduce the incidence of morbidity and mortality as a result of major cardiovascular events.3 Current medical therapies, their benefits, and potential side effects for patients with PAD will be reviewed (Table 1).
Prevalence and Detection
Multiple studies have highlighted clinical limitations in defining and diagnosing PAD.4–6 One such study estimated the prevalence of PAD to be 2.5% in those < 60 years of age, 8.3% in those 60–69 years of age, and 18.8% in those 70 or older. In this and other similar studies, it was found that diagnosing PAD based on intermittent claudication greatly underestimated actual disease prevalence, while use of pulse abnormalities often overestimated it.4,5 In a study by Criqui et al. intermittent claudication occurred in about 2.2% of men and 1.7% of women; pulse abnormalities occurred in 20.3% of men and 22.1% of women. Total PAD prevalence, based on noninvasive testing, was 11.7%, with increasing rates with age and elevated lipid levels.5
In a multicenter cross-sectional study, PAD was detected in 1865/6979 subjects 50 years of age or older, a prevalence of 29%.6 PAD was defined by an ankle brachial index (ABI) 0.90. The overall prevalence of atherosclerotic disease in this group was PAD 13%, CAD and PAD 24%, CAD only 16%, 47% had neither (Figure 1). Also, among all patients with PAD, only 8.7% had classic signs of claudication. Of the patients with prior diagnoses of PAD, 83% were aware of their diagnoses, but only 49% of their physicians had documentation of PAD at the time of screening.
In this study, PVD was slightly more prevalent than previously described.6 Classic claudication symptoms were present in a small fraction of patients with PAD. Additionally, underdiagnosis of PAD in the primary care setting was a common barrier to effective risk modification and treatment.6
Medical Therapy: For Symptom Relief
Peripheral arterial disease is associated with lower extremity claudication and decreased exercise tolerance secondary to lower extremity symptoms. This combination of atherosclerosis and decreased ability to exercise can lead to accelerated progression of atherosclerotic disease and increased risk of major adverse cardiovascular events (MACE).7,8
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Kudos! What a neat way of thniknig about it.
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