Featured Research

from universities, journals, and other organizations

Higher Carotid Arterial Stenting Rates Associated With Poorer Clinical Outcomes

Date:
November 7, 2009
Source:
University of Pennsylvania School of Medicine
Summary:
Among eligible Medicare beneficiaries, increased use of carotid arterial stenting procedures to treat carotid stenosis -- the narrowing of the carotid artery -- is associated with higher rates of mortality and adverse clinical outcomes, including heart attack and stroke, according to researchers.

Among eligible Medicare beneficiaries, increased use of carotid arterial stenting (CAS) procedures to treat carotid stenosis -- the narrowing of the carotid artery -- is associated with higher rates of mortality and adverse clinical outcomes, including heart attack and stroke, according to researchers from the University of Pennsylvania School of Medicine.

Published in the November 2009 issue of the Journal of Vascular Surgery, the study adds to a growing body of research about the effectiveness of stenting for preventing heart attack, stroke, and death. Findings lend further insight into factors influencing how medical technology performs when integrated as treatment among the general Medicare population as opposed to in a controlled clinical trial setting.

For treatment of moderate to severe carotid stenosis, CAS is an alternative to carotid endarterectomy (CEA), a surgical procedure that opens blocked arteries that supply the brain. Introduced in the 1990s, CAS was initially available to Medicare patients only when they were enrolled in clinical trials testing the effectiveness of the minimally invasive procedure. When Medicare expanded coverage of the procedure in 2005, the rate of CAS utilization nearly quadrupled -- from 266 to 1,015 procedures per month -- as the procedure was available for the first time to the general Medicare population, including elderly patients deemed too ill for surgery who would have had no other treatment option.

"Our study showed that in areas where CAS was used more commonly during the coverage era, the clinical outcomes from the combined population of CAS and CEA patients worsened. Nevertheless, stenting should remain a viable and effective treatment option that doctors and patients consider judiciously," says lead author Peter Groeneveld, MD, MS, assistant professor of medicine at the University of Pennsylvania School of Medicine. "CAS is often the only option for patients who are not healthy enough to undergo surgery. However, this state of health may inevitably affect clinical outcomes from the procedure."

Using a national sample of 46,784 Medicare patients older than 66 years of age, the study examined clinical outcomes of both methods in the two 'eras' -- when CAS was covered only in clinical trials and after it became widely covered under Medicare. For each 'era,' researchers assessed clinical outcomes at 90 and 270 days after the procedure in patients who had received either procedure for the first time over a twelve-month period. Key findings showed that in geographic areas that widely adopted CAS during the coverage era, the rate of heart attack, stroke, and death was greater in the 90 and 270 days following the procedure than in the pre-coverage era.

"Key findings from the retrospective study included:

  • When adjusted statistically, more 270-day adverse outcomes in the era of Medicare coverage.
  • In geographic areas with higher adoption rates of CAS during the expanded coverage era, there was a higher rate of 90-day mortality and adverse outcomes, and a higher rate of 270-day mortality and adverse outcomes.
  • No difference in mortality or adverse outcome rates between eras in locations with lower CAS adoption.

Groeneveld, who is also affiliated with the Philadelphia Veterans Affairs Medical Center, has researched the impact of cardiac devices, including drug-eluting stents and implantable cardioverter-defibrillators, for more than 15 years, notes that in a time of healthcare reform, clinical trials and comparative effectiveness research may influence policymakers' decisions about which procedures receive coverage. "Some procedures may receive coverage because clinical trials show them to be more effective, even if by a small percentage, than the current standard treatment. But that rate of effectiveness can change drastically as more patients with unique medical characteristics begin to receive the procedure, and as more doctors with varying skill levels perform it."

In the study, researchers used propensity scoring to match patients across eras and locations in order to reduce bias arising from variables such as sex, race, age, clinical comorbidities, and hospital characteristics, among others. The 'pre-coverage era' was defined as October 1, 2002, through September 30, 2004, and the 'coverage era' was defined as August 1, 2005, through March 31, 2006, after the Centers for Medicare and Medicaid Services implemented a national coverage decision expanding patient eligibility criteria for CAS.


Story Source:

The above story is based on materials provided by University of Pennsylvania School of Medicine. Note: Materials may be edited for content and length.


Cite This Page:

University of Pennsylvania School of Medicine. "Higher Carotid Arterial Stenting Rates Associated With Poorer Clinical Outcomes." ScienceDaily. ScienceDaily, 7 November 2009. <www.sciencedaily.com/releases/2009/11/091107115827.htm>.
University of Pennsylvania School of Medicine. (2009, November 7). Higher Carotid Arterial Stenting Rates Associated With Poorer Clinical Outcomes. ScienceDaily. Retrieved July 29, 2014 from www.sciencedaily.com/releases/2009/11/091107115827.htm
University of Pennsylvania School of Medicine. "Higher Carotid Arterial Stenting Rates Associated With Poorer Clinical Outcomes." ScienceDaily. www.sciencedaily.com/releases/2009/11/091107115827.htm (accessed July 29, 2014).

Share This




More Health & Medicine News

Tuesday, July 29, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Deadly Ebola Virus Threatens West Africa

Deadly Ebola Virus Threatens West Africa

AP (July 28, 2014) West African nations and international health organizations are working to contain the largest Ebola outbreak in history. It's one of the deadliest diseases known to man, but the CDC says it's unlikely to spread in the U.S. (July 28) Video provided by AP
Powered by NewsLook.com
$15B Deal on Vets' Health Care Reached

$15B Deal on Vets' Health Care Reached

AP (July 28, 2014) A bipartisan deal to improve veterans health care would authorize at least $15 billion in emergency spending to fix a veterans program scandalized by long patient wait times and falsified records. (July 28) Video provided by AP
Powered by NewsLook.com
Two Americans Contract Ebola in Liberia

Two Americans Contract Ebola in Liberia

Reuters - US Online Video (July 28, 2014) Two American aid workers in Liberia test positive for Ebola while working to combat the deadliest outbreak of the virus ever. Linda So reports. Video provided by Reuters
Powered by NewsLook.com
Traditional African Dishes Teach Healthy Eating

Traditional African Dishes Teach Healthy Eating

AP (July 28, 2014) Classes are being offered nationwide to encourage African Americans to learn about cooking fresh foods based on traditional African cuisine. The program is trying to combat obesity, heart disease and other ailments often linked to diet. (July 28) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins