Limited data on inhaled steroids for preventing acute mountain sickness

Référence

Zhu X, Liu Y, Li N, He Q. Inhaled budesonide for the prevention of acute mountain sickness: A meta-analysis of randomized controlled trials. Am J Emerg Med 2019;38(8):1627-1634.

Sommaire

These authors searched several databases to find randomized trials comparing ICS with placebo for the prevention of acute mountain sickness. To be included, trials had to use validated tools to diagnose mountain sickness, but also had to include at least 2 additional secondary outcomes. The addition of this latter element may have resulted in fewer included studies. Two authors independently assessed papers for inclusion and assessed the methodologic quality. They ended up with 6 papers from 5 studies with 304 patients. All of the studies lasted between 1 and 4 days and evaluated budesonide inhaled twice daily in doses ranging from 180 mcg to 2000 mcg. The studies were of decent methodologic quality. Overall, 48% of the participants who received ICS developed acute mountain sickness compared with 62% of those who received placebo. Although this result was not statistically significant, it likely represents a lack of power as this difference would translate to a number needed to treat of 8. Similarly, the rate of severe mountain sickness was not significantly lower in the ICS-treated patients (28% vs 36%). There was also a high degree of statistical heterogeneity among these data. The authors report that the participants who received ICS had a lower heart rate (weighted mean difference = 5.4 beats/minute) and higher oxygen saturation (weighted mean difference = 2.4%) than those who received placebo, but frankly these data are pretty meaningless. None of the studies reported adverse event rates.