Volume 5, Number 7: July 2002
A
rational approach to diagnosis and treatment of intermittent claudication.
Reevaluating
the role of phosphodiesterase inhibitors in the treatment of cardiovascular
disease.
The ankle brachial index is
associated with leg function and physical activity: the Walking and Leg
Circulation Study.
Prevalence
and clinical correlates of peripheral arterial disease in the Framingham
Offspring Study.
Reference: Am J Med Sci 2002;323(5):244-51. Intermittent claudication (IC), the first recognizable symptom of peripheral arterial disease, is prevalent among older persons and associated with significant morbidity and mortality. The diagnosis of IC involves taking a thorough patient history, conducting a physical examination with an emphasis on the cardiovascular system, and noninvasive testing with functional assessment. The goals of treatment for IC are to prevent progression of vascular disease and cardiovascular complications and to improve exercise performance, functional status, and quality of life. The cornerstones of therapy are risk-factor modification, particularly smoking cessation, and exercise. In patients for whom non-pharmacologic therapy does not provide adequate pain relief and improvement in physical function, medical therapy with 1 of 2 drugs approved for the treatment of IC may be appropriate. Revascularization or intervention is generally reserved for patients with incapacitating disease. Early diagnosis of IC and implementation of effective therapy can reduce the development of morbidity and mortality.
Reference: Clin Cardiol 2002;25(6):256-62. First developed for clinical use in the late 1980s, the phosphodiesterase inhibitors were found to increase the levels of the ubiquitous second messenger cyclic adenosine monophosphate and could effect changes in vascular tone, cardiac function, and other cellular events. After several early studies using high doses of phosphodiesterase inhibitors in patients with severe heart failure suggested adverse consequences, they fell out of favor. However, recent investigations of phosphodiesterase inhibitors in patients with intermittent claudication have demonstrated profound benefits. Furthermore, these agents have proven useful in prevention of cerebral infarction and coronary restenosis, and their use in the treatment of heart failure is being reevaluated. The reemergence of phosphodiesterase inhibitors can be attributed to a better understanding of dosing and drug-specific pharmacology, the use of concomitant medications, and a recognition of unique ancillary properties; however, their use still requires caution.
Reference: Ann Intern Med 2002;136(12):873-83. BACKGROUND: The ankle brachial index (ABI) is a noninvasive, reliable measure of lower-extremity ischemia. However, the relationship between ABI and lower-extremity function has not been well studied. OBJECTIVE: To describe the association between the ABI and lower-extremity function. DESIGN: Cross-sectional study. SETTING: 3 academic medical centers in the Chicago area. PARTICIPANTS: 740 men and women (460 with peripheral arterial disease). MEASUREMENTS: Accelerometer-measured physical activity over 7 days, 6-minute walk, 4-m walking velocity, standing balance, and ABI. RESULTS: 33% of participants with peripheral arterial disease had intermittent claudication. Fewer than 40% of participants with an ABI less than 0.40 walked continuously for 6 minutes compared with more than 95% of participants with an ABI between 1.00 and 1.50. Compared with an ABI of 1.10 to 1.50, an ABI less than 0.50 was associated with shorter distance walked in 6 minutes (beta-regression coefficient = -523 ft [95% CI, -592 to -454 ft]; P < 0.001), less physical activity (beta = -514.8 activity units [CI, -657 to -373 activity units]; P < 0.001), slower 4-m walking velocity (beta = -0.21 m/s [CI, -0.27 to -0.15 m/s]; P < 0.001), and less likelihood of maintaining a tandem stand for 10 seconds (odds ratio, 0.37 [CI, 0.18 to 0.76]; P = 0.007), after adjustment for typical confounders. Associations between ABI and function were stronger than associations between leg symptoms and function. CONCLUSIONS: The ABI, a noninvasive test that can be performed in a medical office, is more closely associated with leg function in persons with peripheral arterial disease than is intermittent claudication or other leg symptoms. These data support the use of the ABI to identify abnormal lower-extremity function.
Reference: Am Heart J 2002;143(6):961-5. BACKGROUND: Peripheral arterial disease (PAD) is associated with an increased risk for mortality. We sought to assess the prevalence of PAD and its risk factors in a population-based sample. METHODS: We examined 1554 males and 1759 females with a mean age of 59 years who attended a Framingham Offspring Study examination from 1995 to 1998. PAD was defined by an ankle-brachial blood pressure index of <0.9. Age- and sex-adjusted and multivariable logistic regression analyses were performed to identify factors associated with PAD. RESULTS: The prevalences of PAD, current intermittent claudication, lower extremity bruits and surgical intervention were 3.9%, 1.9%, 2.4% and 1.4% in males and 3.3%, 0.8%, 2.3% and 0.5% in females. Hypercholesterolemia, high-density lipoprotein cholesterol, triglyceride, diabetes, hypertension, current smoking, pack-years of smoking, body mass index, fibrinogen, and prevalent coronary disease were associated with PAD in age- and sex-adjusted analyses. Odds ratios and 95% CIs for significant associations identified from multivariable analyses are as follows: each 10 years of age, 2.6 (2.0, 3.4); hypertension, 2.2 (1.4, 3.5); smoking, 2.0 (1.1, 3.4); 10 pack-years of smoking, 1.3 (1.2, 1.4); 50 mg/dL of fibrinogen, 1.2 (1.1, 1.4); 5 mg/dL of high-density lipoprotein, 0.9 (0.8, 1.0); coronary disease, 2.6 (1.6, 4.1). CONCLUSIONS: Smoking cessation and hypertension control are important goals in the aim to reduce PAD and its associated impact on quality of life, functional decline, and risk for subsequent cardiovascular disease. |
