Citing their own work [1] and that of others [2, 3], Roeggla and colleagues conclude that our 25% incidence of acute mountain sickness is an overestimate and that the self-reported questionnaire is an unreliable method for determining the incidence of acute mountain sickness [4].

The incidence of acute mountain sickness is determined by individual susceptibility, the altitude reached, and the rate of ascent [3]. Although the individual susceptibility of Europeans and North Americans is probably similar, the populations differed with respect to fitness, smoking, drinking, and underlying health problems [1, 4]. In addition, the participants' knowledge regarding the purpose of the study differed markedly, as did their rate of ascent. We would expect a decreased incidence of acute mountain sickness in trekkers who, beginning at sea level, took 1 to 4 days to reach huts at moderate altitudes, as opposed to the population we studied, who all flew or drove to their destination resorts. Less than 50% of the population in our study stopped over between 12 and 48 hours at an intermediate elevation; the incidence of acute mountain sickness in those who stayed longer was lower. Only 1% of the population in our study acquired acute mountain sickness after a 36-hour stay at a higher altitude. Of interest is that both reports agree that 25% of travelers to moderate altitude are completely asymptomatic.

Leading experts in the field attempted to resolve questions about how best to determine the incidence of acute mountain sickness by proposing a unified approach to both acute mountain sickness definition and reporting methods [5]. The Lake Louise Consensus document [5] reflects this attempt and acknowledges the need to use self-reported questionnaires for survey studies in combination with clinical examinations for clinical trials. Future reports from various mountain regions using these methods can then be compared to gain a better and more unified understanding of this syndrome. Also, validating these methods by comparison with controls traveling at sea-level is required for future investigations at moderate altitudes [3].

We also disagree that the predominant signs and symptoms of acute mountain sickness are insomnia and periorbital or peripheral edema. Numerous reports, whether by questionnaire or examination, have identified headache and fatigue as the most common findings, with edema found only rarely.

We appreciate Dr. Honsinger's comments and agree that recognition and treatment of these symptoms by practitioners at moderate altitudes is not only compassionate but appropriate.