Featured Research

from universities, journals, and other organizations

ASA Plus Clopidogrel Reduces Heart Attack Risk In Patients With Acute Coronary Syndrome, Study Suggests

Date:
April 28, 2009
Source:
Institute for Quality and Efficiency in Health Care
Summary:
Patients who suffer from acute ischemia of the heart muscle benefit if they use clopidogrel in addition to acetylsalicylic acid (ASA) as early as possible. Their risk of suffering a heart attack is reduced measurably, according to new research.

In order to better prevent blood clots, clopidogrel can be prescribed to patients with acute ischaemia of the heart muscle, in addition to acetylsalicylic acid (ASA). The Institute for Quality and Efficiency in Health Care (IQWiG) has now investigated whether the combination of clopidogrel and ASA actually has a higher benefit for patients than ASA alone.

Related Articles


The final report by IQWiG, published on 31 March 2009, concludes that combination therapy can measurably reduce the risk of a heart attack. This particularly applies if the 2 drugs are used in the early stage of treatment.

ASA and clopidogrel should complement each other's effects

Clopidogrel is an anti-platelet drug ("platelet aggregation inhibitor”) that is used in a similar way to ASA. It inhibits parts of the blood-clotting system, leading to a reduction in platelet clotting (aggregation) and of the subsequent formation of blood clots (thrombi). Clopidogrel thus reduces the risk of occlusion of the arteries and helps prevent heart attacks and strokes. However, the risk of bleeding increases. As the mechanism that affects blood clotting is slightly different from that of ASA, clopidogrel can also be used in combination with ASA in certain cases. It is assumed the 2 drugs complement each other and that the overall inhibitory effect on the formation of blood clots increases.

The combination of clopidogrel and ASA is approved in patients with acute coronary syndrome (ACS), i.e., with an acute stenosis of the coronary blood vessels. On the one hand, this refers to patients with an acute heart attack, which is shown in the electrocardiogram (ECG) as a characteristic elevation of the ECG wave between the "S” and "T” point (ST-segment elevation myocardial infarction, STEMI). On the other hand, it refers to patients with acute severe ischaemia of the heart, but without a heart attack and the typical ST-segment elevation in the ECG. Both types of patients must as a rule immediately receive medical treatment in a hospital.

Previously unpublished data included in the assessment

IQWiG identified a total of 7 randomized controlled trials in which the effects of clopidogrel plus ASA were compared with ASA monotherapy in patients with acute coronary syndrome and which focussed on patient-relevant outcomes. For 2 of these studies, not all necessary data were available in order to interpret their results reliably. They could thus not be included in the assessment. One of these studies (CREDO) was sponsored by the company Sanofi-Aventis, which developed clopidogrel and markets the drug. However, as both studies were relatively small, it is not assumed that they would considerably affect the conclusion of the report.

Of the remaining 5 clinical comparisons, only one referred to patients with ACS without ST-segment elevation. The other studies investigated patients with STEMI/ACS. Sanofi-Aventis provided all data requested by IQWiG for the 3 largest and most important studies. In this way, essential data previously inaccessible to the public could be incorporated into the assessment.

Patients with acute coronary syndrome without ST-segment elevation: clopidogrel plus ASA has no effect on mortality

The results of the only study that could be assessed in patients with ACS without ST-segment elevation provided proof that patients using combination therapy experienced fewer heart attacks. In this study patients were treated for up to 12 months. All-cause mortality was not reduced by the additional use of clopidogrel. At the same time, major bleeding complications occurred more often than with ASA monotherapy. It cannot be conclusively assessed, on the basis of the available data, how long it is meaningful for patients to use combination therapy in order for this therapy to be more beneficial than harmful. Specific studies are lacking here. Overall, however, patients seem to particularly benefit from combination therapy in the early phase of treatment.

Combination therapy in patients with STEMI/ACS can better prevent recurrence of a heart attack

The evidence base is clear regarding the reoccurrence of heart attacks in patients with STEMI/ACS. The data provide proof that the additional use of clopidogrel during the stay in hospital reduces the heart attack rate more strongly than ASA alone does. However, it has so far not been proven that these patients benefit from taking both drugs after leaving the hospital. In addition, the data also provide indications that combination therapy in patients with STEMI/ACS is also more successful regarding the prevention of a stroke.

In contrast to patients with ACS without ST-segment elevation, the additional use of clopidogrel in patients with STEMI/ACS could also have a beneficial effect on all-cause mortality. In the individual studies the results were inconsistent for this outcome; however, a meta-analysis showed a reduced mortality rate, which IQWiG evaluates as an indication of a benefit.

Patients with STEMI/ACS who use clopidogrel also experience bleeding complications more often; however, these are usually minor.

The studies also show that the starting point of therapy is important for treatment success. The data provide indications that patients particularly benefit from combination therapy if treatment starts not later than 6 hours after the first occurrence of symptoms.


Story Source:

The above story is based on materials provided by Institute for Quality and Efficiency in Health Care. Note: Materials may be edited for content and length.


Cite This Page:

Institute for Quality and Efficiency in Health Care. "ASA Plus Clopidogrel Reduces Heart Attack Risk In Patients With Acute Coronary Syndrome, Study Suggests." ScienceDaily. ScienceDaily, 28 April 2009. <www.sciencedaily.com/releases/2009/04/090421101627.htm>.
Institute for Quality and Efficiency in Health Care. (2009, April 28). ASA Plus Clopidogrel Reduces Heart Attack Risk In Patients With Acute Coronary Syndrome, Study Suggests. ScienceDaily. Retrieved March 3, 2015 from www.sciencedaily.com/releases/2009/04/090421101627.htm
Institute for Quality and Efficiency in Health Care. "ASA Plus Clopidogrel Reduces Heart Attack Risk In Patients With Acute Coronary Syndrome, Study Suggests." ScienceDaily. www.sciencedaily.com/releases/2009/04/090421101627.htm (accessed March 3, 2015).

Share This


More From ScienceDaily



More Health & Medicine News

Tuesday, March 3, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Mom Triumphs Over Tragedy, Helps Other Families

Mom Triumphs Over Tragedy, Helps Other Families

AP (Mar. 3, 2015) After her son, Dax, died from a rare form of leukemia, Julie Locke decided to give back to the doctors at St. Jude Children&apos;s Research Hospital who tried to save his life. She raised $1.6M to help other patients and their families. (March 3) Video provided by AP
Powered by NewsLook.com
Woman Convicted of Poisoning Son

Woman Convicted of Poisoning Son

AP (Mar. 3, 2015) A woman who blogged for years about her son&apos;s constant health woes was convicted Monday of poisoning him to death by force-feeding heavy concentrations of sodium through his stomach tube. (March 3) Video provided by AP
Powered by NewsLook.com
Treadmill Test Can Predict Chance Of Death Within A Decade

Treadmill Test Can Predict Chance Of Death Within A Decade

Newsy (Mar. 2, 2015) Johns Hopkins researchers analyzed 58,000 heart stress tests to come up with a formula that predicts a person&apos;s chances of dying in the next decade. Video provided by Newsy
Powered by NewsLook.com
Going Gluten-Free Could Get You A Tax Break

Going Gluten-Free Could Get You A Tax Break

Newsy (Mar. 2, 2015) If a doctor advises you to remove gluten from your diet, you could get a tax deduction on the amount you spend on gluten-free foods. Video provided by Newsy
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:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

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