Prioritisation of treatments for lower extremity peripheral artery disease in low- and middle-income countries

Lower extremity peripheral artery disease (PAD) is increasing in prevalence in low- and middle-income countries creating a large health care burden. Clinical management may require substantial resources but little consideration has been given to which treatments are appropriate for less advantaged countries. The aim of this review was to systematically appraise published data on the costs and effectiveness of PAD treatments used commonly in high-income countries, and for an international consensus panel to review that information and propose a hierarchy of treatments relevant to low- and middle-income countries. Pharmacotherapy for intermittent claudication was found to be expensive and improve walking distance by a modest amount. Exercise and endovascular therapies were more effective and exercise the most cost-effective. For critical limb ischaemia, bypass surgery and endovascular therapy, which are both resource intensive, resulted in similar rates of amputation-free survival. Substantial reductions in cardiovascular events occurred with use of low cost drugs (statins, ACE inhibitors, anti-platelets) and smoking cessation. The panel concluded that, in low- and middle-income countries, cardiovascular prevention is a top priority, whereas a lower priority should be given to pharmacotherapy for leg symptoms and revascularisation, except in countries with established vascular units

Development and validation of an ankle brachial index risk model for the prediction of cardiovascular events

Background The ankle brachial index (ABI) is related to risk of cardiovascular events independent of the Framingham risk score (FRS). The aim of this study was to develop and evaluate a risk model for cardiovascular events incorporating the ABI and FRS. Design An analysis of participant data from 18 cohorts in which 24,375 men and 20,377 women free of coronary heart disease had ABI measured and were followed up for events. Methods Subjects were divided into a development and internal validation dataset and an external validation dataset. Two models, comprising FRS and FRS + ABI, were fitted for the primary outcome of major coronary events. Results In predicting events in the external validation dataset, C-index for the FRS was 0.672 (95% CI 0.599 to 0.737) in men and 0.578 (95% CI 0.492 to 0.661) in women. The FRS + ABI led to a small increase in C-index in men to 0.685 (95% CI 0.612 to 0.749) and large increase in women to 0.690 (95% CI 0.605 to 0.764) with net reclassification improvement (NRI) of 4.3% (95% CI 0.0 to 7.6%, p = 0.050) and 9.6% (95% CI 6.1 to 16.4%, p < 0.001), respectively. Restricting the FRS + ABI model to those with FRS intermediate 10-year risk of 10 to 19% resulted in higher NRI of 15.9% (95% CI 6.1 to 20.6%, p < 0.001) in men and 23.3% (95% CI 13.8 to 62.5%, p = 0.002) in women. However, incorporating ABI in an improved newly fitted risk factor model had a nonsignificant effect: NRI 2.0% (95% CI 2.3 to 4.2%, p = 0.567) in men and 1.1% (95% CI 1.9 to 4.0%, p = 0.483) in women. Conclusions An ABI risk model may improve prediction especially in individuals at intermediate risk and when performance of the base risk factor model is modest

Physics and technology of the Next Linear Collider: a report submitted to Snowmass '96

We present the current expectations for the design and physics program of an e+e- linear collider of center of mass energy 500 GeV -- 1 TeV. We review the experiments that would be carried out at this facility and demonstrate its key role in exploring physics beyond the Standard Model over the full range of theoretical possibilities. We then show the feasibility of constructing this machine, by reviewing the current status of linear collider technology and by presenting a precis of our `zeroth-order' design