Continuing Clopidogrel Plus Aspirin beyond 12 Months after Stenting Appears No More Effective for Cardiovascular Outcomes than Aspirin Alone

DynaMed Weekly Update - Volume 5, Issue 14

Joint guidelines (from the American Heart Association, American College of Cardiology, and others) recommend dual antiplatelet therapy (clopidogrel plus aspirin) for at least 1 year following placement of a drug-eluting stent (Circulation 2007 Feb 13;115(6):813). A pair of recent open-label trials, analyzed together, evaluated the effects of switching to aspirin alone after 1 year. A total of 2,701 patients who were free of major cardiac events and bleeding for ? 12 months following PCI with a drug-eluting stent were randomized to continued dual antiplatelet therapy vs. aspirin alone. In a median follow-up of 19.2 months, there were no significant differences in the primary outcome, a composite of myocardial infarction and cardiovascular death (1.5% vs. 0.9%). There were also no significant differences in the rates of all-cause mortality (1.5% vs. 1%), myocardial infarction (0.7% vs. 0.5%), stroke (0.7% vs. 0.3%), stent thrombosis (0.4% vs. 0.3%), or revascularization (2.7% vs. 1.9%) (level 2 [mid-level] evidence). Dual therapy was associated with a borderline increase in the composite of myocardial infarction, stroke, or all-cause mortality (2.6% vs. 1.5% p = 0.051, NNH 90) (N Engl J Med. 2010 Apr 15;362(15):1374).

For more information, see the Medications before, during and after percutaneous coronary intervention topic in DynaMed.

Rifaximin May Improve Remission and Reduce Hospitalization for Hepatic Encephalopathy

Hepatic encephalopathy is a common complication of liver cirrhosis, often requiring hospitalization. A recent trial evaluated the efficacy of rifaximin to maintain remission in 299 patients with recurrent hepatic encephalopathy due to chronic liver disease. Patients were randomized to rifaximin 550 mg twice daily vs. placebo for 6 months. Lactulose use was continued in patients receiving it at baseline (91%). Rifaximin was associated with reduced recurrence of encephalopathy (22.1% vs. 45.9%, p < 0.001, NNT 4) (level 2 [mid-level] evidence). There was also a lower rate of hospitalization for hepatic encephalopathy in patients treated with rifaximin (13.6% vs. 22.6%, p = 0.01, NNT 9). Both groups had high rates of minor adverse events (80% vs. 79.9%). The most common were nausea, diarrhea, and fatigue (N Engl J Med 2010 Mar 25;362(12):1071).

For more information, see the Rifaximin topic in DynaMed.