plavix + PPI again? 老師生氣了，目前唯一的RCT是COGENT study > 證明沒有害!

Clopidogrel plus a Proton-Pump Inhibitor: Prescription for Cardiovascular Events?

Yet another retrospective cohort study adds to the confusion.

The metabolic effects of proton-pump inhibitors (PPIs) on the cytochrome P450 system have been hypothesized to inhibit the antiplatelet activity of clopidogrel. Although recent studies have suggested that concurrent use of clopidogrel and PPIs is safe and effective for patients with cardiovascular disease (JW Gastroenterol Apr 2 2010), evidence about whether such inhibition of antiplatelet activity increases risk for adverse cardiovascular events has been mixed.

To examine this issue again, U.S. researchers retrospectively studied a cohort of 1033 enrollees in a multistate health insurance plan who had been discharged from the hospital after myocardial infarction (MI) or coronary stent placement and were subsequently treated with clopidogrel and a PPI concomitantly. These patients were matched with patients who had similar cardiovascular profiles and were being treated with clopidogrel alone.

During follow-up of 360 days, rehospitalization for MI was more common among patients receiving clopidogrel plus a PPI than among those receiving clopidogrel alone (9.7 vs. 4.1 events per 100 person-years; adjusted hazard ratio, 1.93; P=0.03), as was the combined rate of rehospitalization for either MI or coronary stent placement (27.6 vs. 14.3 events per 100 person-years; AHR, 1.64; P=0.005). In a subset analysis of 659 patients who were receiving the PPI pantoprazole plus clopidogrel (compared with matched pairs who were receiving clopidogrel alone), concomitant therapy was associated with higher risk for the combined rate of rehospitalization for MI or coronary stent placement (33.8 vs. 14.1 events per 100 person-years; AHR, 1.91; P=0.008).

Comment: Analyses suggesting potential harm from combination use of clopidogrel and a PPI have been retrospective and, therefore, limited in their adjustment for potential confounders; moreover, the significant hazard ratios (most <2.0) href="http://cardiobrief.org/2009/09/24/tct-cogent-provides-reassurance-on-use-of-ppis-with-clopidogrel/">COGENT) that compared outcomes of treatment with combination clopidogrel plus a PPI (omeprazole) versus clopidogrel alone showed no difference in cardiovascular outcomes and a significantly lower rate of adverse gastrointestinal events in the combination-therapy patients. Repeatedly publishing methodologically flawed analyses in highly respected journals only perpetuates confusion around this controversial topic.

— David A. Johnson, MD

Published in Journal Watch Gastroenterology May 21, 2010

Citation(s):

Stockl KM et al. Risk of rehospitalization for patients using clopidogrel with a proton pump inhibitor. Arch Intern Med 2010 Apr 26; 170:704.

• Original article (Subscription may be required)
• Medline abstract (Free)

評論者生氣了，因為目前所有不利合用的study都是retrospective study, 而唯一的RCT trial 是cogent，沒有publish, 而cogent是企業贊助的……

http://docs.google.com/present/edit?id=0AW78nGJMQBk7ZGc1d3FjYmpfMTgxZ200NjV3ZHM&hl=zh_TW