G.C. Leng

Abstract Objective : To determine whether a low ankle brachial pressure index is associated with an increased risk of cardiovascular events and death, and whether the prediction of such events could be improved by including this index. Design : Cohort study. Setting : 11 practices in Edinburgh, Scotland. Subjects : 1592 men and women aged 55–74 years selected at random from the age-sex registers of 11 general practices and followed up for 5 years. Main outcome measures : Incidence of fatal and non-fatal cardiovascular events and all cause mortality. Results : At baseline 90 (5.7%) of subjects had an ankle brachial pressure index </=0.7, 288 (18.2%) had an index </=0.9, and 566 (35.6%) </=1.0. After five years subjects with an index </=0.9 at baseline had an increased risk of non-fatal myocardial infarction (relative risk 1.38, 95% confidence interval 0.88 to 2.16), stroke (1.98, 1.05 to 3.77), cardiovascular death (1.85, 1.15 to 2.97), and all cause mortality (1.58, 1.14 to 2.18) after adjustment for age, sex, coronary disease, and diabetes at baseline. The ability to predict subsequent events was greatly increased by combining the index with other risk factors—for example, hypertensive smokers with normal cholesterol concentrations had a positive predictive value of 25.0%, increasing to 43.8% in subjects with a low index and decreasing to 15.6% in those with a normal index. Conclusion : The ankle brachial pressure index is a good predictor of subsequent cardiovascular events, and improves on predictions by conventional risk factors alone. It is simple and accurate and could be included in routine screening of cardiovascular status. Key messages In this study individuals with a low ankle brachial pressure index had an increased risk of fatal and non-fatal cardiovascular events The index was a good predictor of subsequent cardiovascular events, and improved that of conventional risk factors alone The ankle brachial pressure index could be included in routine screening of cardiovascular status Individuals with a low ankle brachial pressure index require additional monitoring, and might benefit from aspirin or other secondary preventive measures

BACKGROUND: Surgical bypass of an occluded arterial segment is one of the mainstay treatments for patients with critical limb ischaemia (CLI). However, it was introduced without formal evaluation. OBJECTIVES: To determine the effects of bypass surgery in patients with CLI. SEARCH STRATEGY: The Cochrane Peripheral Vascular Diseases Group (PVD) searched their trials register (last searched November 2007) and the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library (last searched Issue 4, 2007). Principal trial investigators were also contacted. SELECTION CRITERIA: All randomised controlled trials (RCTs) of bypass surgery versus control or any other treatment. DATA COLLECTION AND ANALYSIS: For the update one author and PVD editorial staff extracted data and assessed trial quality. Unpublished data were obtained from trial investigators. Data were analyzed using Peto odds ratio (OR) or weighted mean difference (fixed and random effects models). MAIN RESULTS: Nineteen trials were identified. Eight involved a total of just over 1200 patients. Four trials compared bypass surgery with angioplasty (PTA) and one each with thromboendarterectomy, thrombolysis, exercise, and spinal cord stimulation. Four included patients with intermittent claudication (IC) and CLI, two were restricted to claudicants, and two to CLI. Vein grafts were used for distal reconstructions and synthetic prostheses for aorto-iliac or ilio-femoral bypasses. Six trials included mortality. In general, trial quality was good; blinding was not possible. Mortality and amputation rates did not differ significantly between bypass surgery and PTA; primary patency was significantly higher in the bypass group after 12 months (Peto OR 1.6, 95% CI 1.0 to 2.6) but not after four years (P = 0.14). In patients with lower CLI, surgery was associated with increased surgical complications (Peto OR 2.69, 95% CI 1.87 to 3.86) and longer hospital stays during the first year, mean stay 46.1 days (SD 53.9) compared with 36.4 days (SD 51.4) for those receiving PTA (P < 0.0001). Amputation rates were significantly lower in bypass compared with thrombolysis (Peto OR 0.2, 95% CI 0.1 to 0.6); mortality rates did not differ. Blood flow restoration was significantly greater in bypass than in thromboendarterectomy patients (Peto OR 9.2, 95% CI 1.7 to 50.6); mortality and amputation rates did not differ. Bypass surgery outcomes did not differ significantly from exercise or spinal cord stimulation. AUTHORS' CONCLUSIONS: There is limited evidence for the effectiveness of bypass surgery compared with other treatments; no studies compared bypass to no treatment. Further large trials are required.

STUDY OBJECTIVE: To determine associations between physical activity at age 35-45 years with peripheral arterial disease and cardiovascular risk factors at age 55-74 years. DESIGN: Cross sectional survey of the general population--Edinburgh Artery Study. The presence of peripheral arterial disease was determined using the WHO/Rose questionnaire on intermittent claudication, and the ankle brachial pressure index at rest and during reactive hyperaemia. Levels of physical activity undertaken at the time of the survey and at the times the subjects were aged 35-45 years were measured by self administered recall questionnaire. SETTING: City of Edinburgh, Scotland. PARTICIPANTS: Altogether 1592 men and women aged 55 to 74 years, selected from the age-sex registers of 10 general practices spread geographically and socioeconomically throughout the city. MAIN RESULTS: Participation in moderate or strenuous activity when aged 35-45 years was reported by 66% of men and 40% of women. In men, but not in women, less peripheral arterial disease (measured by an increasing trend in the ankle brachial pressure index) was found with increasing amounts of exercise at age 35-45 years (p < 0.001). Higher levels of exercise at age 35-45 years were associated with lower blood viscosity (p < 0.05) and plasma fibrinogen levels (p < 0.05) in men and women aged 55-74 years, and also with higher current alcohol intake (p < 0.001) and high density lipoprotein cholesterol concentrations (p < 0.01) in women aged 55-74 years. After adjustment for age, sex, life-time smoking, social class, body mass index, and alcohol intake, the association between leisure activity aged 35-45 years and the ankle brachial pressure index aged 55-74 years remained highly significant in men who had at some time smoked (p < 0.001) but not in men or women who had never smoked (p > 0.05). CONCLUSION: The risk of peripheral arterial disease, particularly among male smokers, is inversely related to previous physical activity in early middle age, suggesting a protective effect of exercise.