M. Burtscher et al., Effects of aspirin during exercise on the incidence of high-altitude headache: A randomized, double-blind, placebo-controlled trial, HEADACHE, 41(6), 2001, pp. 542-545
Objective.-To evaluate the efficacy of aspirin for headache when exercising
during acute high-altitude exposure.
Background.-Aspirin effectively prevents headache when mostly resting durin
g acute high-altitude exposure. However, the majority of individuals expose
d to high altitude perform mountaineering activities, which might trigger h
eadache,
Design.-Randomized, double-blind, placebo-controlled trial.
Methods.-Thirty-one healthy volunteers (20 men, 11 women; aged 22 to 59 yea
rs) were transported to an altitude of about 3000 meters and climbed up to
3800 meters. They then descended to a mountain hut at 3480 meters and spent
2 nights there. Tablets (placebo or 320 mg aspirin) were administered thre
e times at 4-hour intervals, beginning 2 hours before arrival at high altit
ude. Headache scoring and measurements of heart rate, blood pressure, and a
rterial oxygen saturation were performed.
Results.-Ninety-three percent (14 of 15) of the placebo group and 56% (9 of
16) of the aspirin group developed headache when mountaineering activities
were performed during acute exposure to high altitude (P < .05). Five hour
s after arrival at high altitude, mean resting oxygen saturation was 86.1%
+/- 2.1% with aspirin and 85.7 % +/- 2.8% with placebo (P=.66). However, su
bjects in the aspirin group developed headache at saturation values less th
an or equal to 86%, while those in the placebo group developed headache at
saturation values less than 90%,
Conclusions.-Although the prophylactic intake of about 1 gram of aspirin re
duced the headache incidence when exercising during acute high-altitude exp
osure, the incidence of headache was higher than previously shown for resti
ng conditions. Aspirin resulted in tolerance to lower arterial oxygen satur
ation without development of headache; exercise had the opposite effect.