Also Included In: Seniors / Aging; Heart Disease
Article Date: 20 Aug 2013 - 0:00 PDT Current ratings for:
Personalized drug dosing necessary for older heart patients
Older heart patients present unique challenges for determining the optimal dosages of medications, so a new study from researchers at Duke Medicine offers some rare clarity about the use of drugs that are used to treat patients with heart attacks.
For certain heart patients older than age 75, a half-dose of the anti-platelet drug prasugrel works about as well as the typical dosage of clopidogrel, according to a team led by the Duke Clinical Research Institute that looked at a sub-study of a large clinical trial.
"As people live longer throughout the world, it's increasingly important to establish appropriate treatments for conditions such as acute coronary syndromes that commonly occur later in life," said Matthew T. Roe, M.D., MHS, associate professor of medicine at Duke and lead author of a study published Aug. 20, 2013, in the journal Circulation.
"These patients are very vulnerable to side effects, including bleeding, if therapies are not properly dosed," Roe said. "Additionally, existing practice guidelines have few specific recommendations for older patients with acute coronary syndromes as little evidence has been accrued from prior clinical trials in this population."
People older than age 75 comprise less than 10 percent of the U.S. population, but account for 35 percent of patients with acute coronary syndrome (ACS), which includes a recent heart attack or unstable chest pain. ACS is typically treated with anti-platelet therapies.
Earlier studies, for example, had shown that the platelet inhibitor prasugrel reduced the risk of adverse outcomes compared with clopidogrel in ACS patients undergoing coronary stent implantation. Those studies used a 60-mg initial dose followed by a 10-mg/day maintenance dose.
At that dosage level, however, patients older than age 75 had an increased risk of intracranial and fatal bleeding, as did younger patients weighing 132 pounds or less. The results led to warnings by the U.S. Food and Drug Administration and the European Medicines Agency for the use of the 10 mg/day maintenance dose of prasugrel in those populations, and consideration of a reduced dose (5 mg/day) to mitigate bleeding complications.
To examine whether older patients might benefit from a lower dosage of prasugrel, the Duke-led researchers analyzed more than 2,000 older patients who participated in a large trial called TRILOGY ACS that compared prasugrel with clopidogrel to manage acute coronary syndromes without coronary stent implantation or coronary bypass surgery.
The findings from this study, the first long-term data on outcomes specifically from elderly patients treated with the reduced dose of prasugrel, determined that a smaller dosage of 5-mg/day of prasugrel presented no greater risk of bleeding problems than the commonly prescribed 75-mg dose of clopidogrel in the elderly population.
"The findings from our study indicate how difficult it is to identify the right dose of anti-clotting medications for the elderly, to improve outcomes after a heart attack," said co-author Magnus Ohman, professor of medicine at Duke and chairman of the TRILOGY ACS study. "While a lower dose seemed intuitive, it was safe but not more effective. Future dedicated studies need to continue to find the right therapies for the vulnerable elderly patients."
Article adapted by Medical News Today from original press release. Click 'references' tab above for source.Visit our cardiovascular / cardiology section for the latest news on this subject.
The Association of Early Physician Follow-up and 30-Day Readmission after Non-ST-Segment Elevation Myocardial Infarction among Older Patients
In addition to Roe and Ohman, study authors include Shaun Goodman; Susanna Stevens; Judith Hochman; Shmuel Gottlieb; Bikur Cholim; Felipe Martinez; Anthony Dalby; William Boden; Harvey White; Dorairaj Prabhakaran; Kenneth Winters; Philip Aylward; Jean-Pierre Bassand; Darren McGuire; Diego Ardissino; Keith A.A. Fox; and Paul Armstrong. CIRCULATIONAHA.113.004569; Published online before print August 14, 2013, doi: 10.1161/?CIRCULATIONAHA.113.004569
The drug companies Eli Lilly and Daiichi Sankyo, which market and make prasugrel, funded the TRILOGY ACS study.
Roe receives grant funding and/or consulting fees from Lilly and Daiichi Sankyo. Ohman receives grant funding and travel expenses from the Lilly and Daiichi Sankyo. More detailed disclosures are provided in the published study.
Duke University Medical Center
Please use one of the following formats to cite this article in your essay, paper or report:MLA
20 Aug. 2013.
Please note: If no author information is provided, the source is cited instead.
'Personalized drug dosing necessary for older heart patients'
Please note that we publish your name, but we do not publish your email address. It is only used to let you know when your message is published. We do not use it for any other purpose. Please see our privacy policy for more information.
If you write about specific medications or operations, please do not name health care professionals by name.
All opinions are moderated before being included (to stop spam). We reserve the right to amend opinions where we deem necessary.
Contact Our News Editors
For any corrections of factual information, or to contact the editors please use our feedback form.
Please send any medical news or health news press releases to:
Note: Any medical information published on this website is not intended as a substitute for informed medical advice and you should not take any action before consulting with a health care professional. For more information, please read our terms and conditions.
No comments:
Post a Comment