The reversal on perioperative beta blockade: there's more

I blogged some concerns on this topic the other day. Now we have this new paper in Heart. So what did they do? They excluded the discredited publications on the topic and did a meta-analysis on what was left:

Results Nine secure trials totalling 10 529 patients, 291 of whom died, met the criteria. Initiation of a course of β-blockers before surgery caused a 27% risk increase in 30-day all-cause mortality (p=0.04)...

Conclusions Guideline bodies should retract their recommendations based on fictitious data without further delay. This should not be blocked by dispute over allocation of blame. The well-conducted trials indicate a statistically significant 27% increase in mortality from the initiation of perioperative β-blockade that guidelines currently recommend. Any remaining enthusiasts might best channel their energy into a further randomised trial which should be designed carefully and conducted honestly.

It's been tweeted around today that this represents a big reversal. Indeed it does, though not as abrupt as it might appear. Guideline writers began narrowing their recommendations for perioperative beta blockade back in 2009, since which time the only remaining class I recommendation regarding perioperative beta blockers is that they be continued perioperatively for those patients already taking them for a class I indication. Initiation in various high risk situations has since 2009 carried a IIa recommendation. The class I indication will likely stay. The IIa ones will likely go away in view of the new meta-analysis.