Dabare Dilan, Lo Tammy T H, McCormack David J, Kung Victor W S
Department of Surgery, Poole General Hospital, Poole, UK.
Interact Cardiovasc Thorac Surg. 2012 Apr;14(4):399-405. doi: 10.1093/icvts/ivr106. Epub 2012 Jan 19.
A best-evidence topic in vascular surgery was written according to a structured protocol. The question addressed was whether screening asymptomatic individuals for an abdominal aortic aneurysm (AAA) is feasible and improves disease-free survival. Seven studies presented the best evidence to answer the clinical question. The author, journal, date and country of publication, patient group studied, study type, relevant outcomes, results and limitations of the studies are tabulated. In total, four randomized population-based studies have evaluated ultrasound screening for AAA: two British studies, Multicentre Aneurysm Screening Study (MASS) and the Chichester trial, and one each in Viborg County, Denmark and Western Australia. Participants were randomized to receive an invitation to screen or not. The MASS trial randomized 67 770 men, followed participants over 10 years and concluded that screening would almost half AAA-related deaths in men aged 65-74 years. The smaller Chichester trial included only 6040 men but demonstrated a 42% reduction in AAA-related mortality at 5 years, with ongoing benefit at 15 years (11% reduction). The Viborg County trial recruited 12 639 men aged 64-73 years, showed a 66% reduction in AAA-related mortality over 14 years. Finally, the Western Australia trial evaluated 41 000 men but included an older population of 65-83 years old. No benefit was seen in this age group but subgroup analysis of men aged 65-74 showed a significant mortality benefit. Only a small or insignificant benefit in all-cause mortality was seen in any of these studies. A recent meta-analysis of these trials has shown a significant benefit in AAA-related mortality in the long term and concluded that AAA screening is superior to other established screening programmes. The cost-effectiveness of screening was assessed in the MASS and Viborg County trials and was found to be substantially below the cost threshold set by the National Institute of Clinical Excellence for acceptance of interventions. Quality of life was assessed in the MASS and in a case-control study and showed no adverse effects that outweigh the benefits. We concluded that ultrasound screening for AAAs has met all the criteria to become a screening programme and would substantially reduce disease-related death with no adverse effect on quality of life.
一篇血管外科的最佳证据主题文章是按照结构化协议撰写的。所探讨的问题是，对无症状个体进行腹主动脉瘤（AAA）筛查是否可行以及能否改善无病生存期。七项研究提供了回答该临床问题的最佳证据。各项研究的作者、期刊、发表日期、国家、所研究的患者群体、研究类型、相关结局、结果及局限性均列表展示。
总体而言，共有四项基于人群的随机研究评估了AAA的超声筛查：两项英国研究，即多中心动脉瘤筛查研究（MASS）和奇切斯特试验，丹麦维堡郡及西澳大利亚各有一项。参与者被随机分为接受筛查邀请组和未接受筛查邀请组。MASS试验随机选取了67770名男性，对参与者进行了10年随访，得出结论：筛查可使65至74岁男性中与AAA相关的死亡人数几乎减半。规模较小的奇切斯特试验仅纳入了6040名男性，但显示5年时与AAA相关的死亡率降低了42%，15年时仍有持续益处（降低11%）。维堡郡试验招募了12639名64至73岁的男性，显示14年间与AAA相关的死亡率降低了66%。最后，西澳大利亚试验评估了41000名男性，但纳入的是65至83岁的老年人群体。该年龄组未观察到益处，但对65至74岁男性的亚组分析显示有显著的死亡率益处。在这些研究中，任何一项在全因死亡率方面均仅显示出微小或不显著的益处。最近对这些试验的一项荟萃分析表明，从长期来看，AAA筛查在与AAA相关的死亡率方面有显著益处，并得出结论：AAA筛查优于其他既定的筛查项目。MASS试验和维堡郡试验评估了筛查的成本效益，发现其大大低于国家临床优化研究所设定的干预措施可接受成本阈值。MASS试验以及一项病例对照研究评估了生活质量，结果显示没有不利影响超过益处。我们得出结论，AAA的超声筛查已满足成为一项筛查项目的所有标准，并且将大幅降低与疾病相关的死亡，对生活质量无不利影响。
