随机临床试验的结果在真实世界中的外推价值有限

基于医疗保险和医疗保险服务中心颈动脉支架植入术（CAS）数据库（2005年~2009年）的一项大型回顾性队列研究结果显示，年龄所致竞争风险的存在和医生技能熟练水平总体较低的局面限制了医疗保险（Medicare）患者的CAS获益。

该患者人群的围手术期死亡率是CREST 和SAPPHIRE关键临床研究中的患者人群的2倍以上[doi:10.1001/jamaneurol.2014.3638]。

在这项回顾性研究中，布莱根妇女医院的Jessica J. Jalbert医生及其同事对超过22,000例患者进行了分析。患者平均年龄超过76岁，60.5%为男性，94%为白人。约半数患者有症状，91.2%患者具有高手术风险，97.4%患者的颈动脉狭窄程度≥70%。

约80%进行CAS的患者达到SAPPHIRE试验定义的适应证标准，约半数患者达到至少一项SAPPHIRE试验定义的高手术风险标准。

结果显示，在平均约2年的随访中，以下患者的死亡风险超过33.3%，包括年龄≥80岁的患者（死亡风险41.5%）、有症状的患者（37.3%）、具有高手术风险且有症状的颈动脉狭窄程度≥50%的患者（37.3%）、非择期入院的患者（36.2%）。此外，在无症状的患者中，年龄≥80岁的患者的围手术期后死亡风险超过33.3%。

需特别指出的是，这些进行CAS的医疗保险患者中仅有少数患者的经治医生的技能熟练水平达到临床试验要求的技能熟练水平。这是个潜在的问题，因为年手术量少和手术医生经验不足与围手术期死亡率增加相关。

大部分CAS（98.4%）由男医生进行，52.9%由心脏病专科医生进行，79.4%由医生团队进行，42.5%由南部医生进行。医生和医院去年进行的CAS平均例数分别仅为13.9 例和29.8例。这意味着超过80%的医生未达到SAPPHIRE试验要求的最低CAS手术量和/或最低并发症发生率，超过90%的医生未达到CREST试验要求。

该研究表明，随机临床试验结果的外推价值有限。

Jalbert博士表示，需在真实世界中开展比较CAS、颈动脉内膜切除术和药物治疗的观察性研究，以明确哪种颈动脉狭窄治疗方案对医疗保险患者的效果最好。

该研究获美国健康和人类服务部卫生保健研究与质量局资助。研究者声明无相关经济利益冲突。

爱思唯尔版权所有 未经授权请勿转载！

The presence of competing risks and overall lower levels of provider proficiency appeared to limit the benefits of carotid artery stenting in Medicare beneficiaries, according to the results of a large retrospective cohort study of the Centers for Medicare & Medicaid Services CAS database (2005-2009).

Periprocedural mortality was more than twice the rate in this patient population than in those earlier patients those involved in the pivotal CREST and SAPPHIRE clinical trials, according to a report published online Jan. 12 in JAMA Neurology [doi:10.1001/jamaneurol.2014.3638].

“The higher risk of periprocedural complications and the burden of competing risks owing to age and comorbidity burden must be carefully considered when deciding between carotid stenosis treatments for Medicare beneficiaries,” according to Jessica J. Jalbert, Ph.D., of Brigham and Women’s Hospital and Harvard Medical School, Boston, and her colleagues.

Over 22,000 patients were assessed in the study. The mean patient age was just over 76 years, 60.5% were men, and 94% were white. Approximately half were symptomatic, 91.2% were at high surgical risk, and 97.4% had carotid stenosis of at least 70%.

Almost 80% of the patients undergoing carotid artery stenting (CAS) met the SAPPHIRE trial indications and about half met at least one of the SAPPHIRE criteria for high surgical risk.

In the mean follow-up of approximately 2 years, mortality risks exceeded one-third for patients who were 80 years of age or older (41.5% mortality risk), symptomatic (37.3% risk), at high surgical risk with symptomatic carotid stenosis of at least 50% (37.3% risk), or admitted nonelectively (36.2% risk). In addition, among asymptomatic patients, mortality after the periprocedural period exceeded one-third for patients at least 80 years old.

Of particular concern, few of these Medicare beneficiaries undergoing CAS as per the National Coverage Determinations were treated by providers with proficiency levels similar to those required in the clinical trials. This is a potential problem because lower annual volume and early operator experience are associated with increased periprocedural mortality, the authors wrote.

CAS was performed primarily by male physicians (98.4%), specializing in cardiology (52.9%), practicing within a group (79.4%), and residing in the South (42.5%). The mean number of past-year CAS procedures performed was only 13.9 for physicians and 29.8 for hospitals. This translated to more than 80% of the physicians not meeting the minimum CAS volume requirements and/or minimum complication rates of the SAPPHIRE trial, and more than 90% not meeting the requirements of the CREST trial.

“Our results may support concerns about the limited generalizability of [randomized clinical trial] findings,” the researchers stated.

“Real-world observational studies comparing CAS, carotid endarterectomy, and medical management are needed to determine the performance of carotid stenosis treatment options for Medicare beneficiaries,” Dr. Jalbert and her colleagues concluded.

The authors reported no relevant disclosures. The study was funded by the Agency for Healthcare Research and Quality, U.S. Department of Health & Human Services.

 

Copyright © 2015 Frontline Medical News, a Frontline Medical Communications, Inc. company. All rights reserved. This material may not be published, broadcast, copied or otherwise reproduced or distributed without the prior written permission of Frontline Medical Communications, Inc.