New anticoagulant works well for people with atrial fibrillation

Dabigatran is an oral thrombin inhibitor and a potential alternative to warfarin for people with atrial fibrillation. The new drug has several theoretical advantages over warfarin: it is less susceptible to drug interactions, and people taking dabigatran do not need monitoring or dose adjustments.

Dabigatran also helps prevent ischaemic strokes and systemic emboli, and compared well against warfarin in a recent large trial. The lower dose investigated (110 mg twice daily) worked as well as warfarin over 2 years (1.53% v 1.69% experienced stroke or systemic embolism, relative risk 0.91, 95% confidence interval 0.74 to 1.11), but the higher dose (150 mg twice daily) worked better (1.11% v 1.69%, 0.66; 95% CI 0.53 to 0.82). People given either dose of dabigatran had significantly fewer haemorrhagic strokes than controls given warfarin (0.38% per year v 0.12% per year (110 mg dabigatran) and 0.1% per year (150 mg dabigatran); P<0.001 for both comparisons).⇑

An accompanying editorial says this industry sponsored trial is reliable and suggests that some patients with atrial fibrillation could benefit from switching to dabigatran (doi:10.1056/NEJMe0906886) The lower dose seemed safer overall, but the higher dose looked more effective. Problems associated with this new drug include an unexplained increase in heart attacks. In addition, patients taking the higher dose also had significantly more gastrointestinal bleeds than controls taking warfarin, possibly because dabigatran capsules contain tartaric acid to lower stomach pH and aid absorption.

Uncertainty continues over antiviral agents for Bell’s palsy

A meta-analysis of randomised trials has confirmed that corticosteroids are an effective treatment for Bell’s palsy (relative risk of unsatisfactory recovery 0.69, 95% CI 0.55 to 0.87). The analysis also confirms that antiviral agents are not effective when used alone (1.14, 0.80 to 1.62). Uncertainty remains over the efficacy of using both treatments together, the authors find a suggestion that adding antiviral agents to corticosteroids …