We adore dexamethasone here at EMLoN headquarters. A pharmacy stocked solely with ketamine, droperidol, and dexamethasone could carry you far in life. Unfortunately, because of our established bias, the challenge then arises to reconcile the actual results of a trial with what is so desperately wished to be true.
This is a randomized, double-blinded, non-inferiority trial comparing single-dose dexamethasone with five days of prednisone in the treatment of asthma with acute exacerbation. Single-dose and double-dose dexamethasone protocols have been evaluated in pediatric trials of reasonable size, but data in adults has been lacking. However, many clinicians – including myself – have assumed generalizability of the pediatric findings to adults, and have been using single-dose dexamethasone protocols for years.
If only one takeaway can be had from this trial, it is: never, ever, skimp on sample size. Far easier said than done, of course, but due to the complex structure and assumptions required for non-inferiority trials, this is a negative trial. There were 465 subjects randomized – but 89 excluded from analysis as either subsequent admissions or as lost to follow-up. Of the remaining 376 patients, 9.8% of the prednisone group demonstrated Emergency Department recidivism compared with 12.1% of dexamethasone. This 2.3% difference between groups, however, suffers a 95% of -4.1 to 8.6%, and exceeds the pre-determined clinically-relevant non-inferiority margin of 8%.
So, unfortunately, we still do not have a precise estimate for the effectiveness difference between a prednisone-based strategy and dexamethasone. Considering the healthcare burden of asthma in our Emergency Departments, it is somewhat surprising we still have such a paucity of data – as even a small difference in effectiveness may have profound effects on Emergency Department utilization. In the end, it comes down to where you lay on the spectrum of pre-study odds for non-inferiority or equivalence. For me, the guarantee of compliance with treatment derived from a single-dose of dexamethasone outweighs the continued uncertainty over its true effectiveness, and this study gives me no cause to change my practice.
“A Randomized Controlled Noninferiority Trial of Single Dose of Oral Dexamethasone Versus 5 Days of Oral Prednisone in Acute Adult Asthma”