Incidence of Acute Mountain Sickness at Intermediate Altitudes-Reply

In Reply.—  The purpose of the article entitled "Incidence of Acute Mountain Sickness at Intermediate Altitude" was to alert physicians that this is a real syndrome. Dr Houston clearly concurs. Where we differ is in our definitions of "acute mountain sickness." Our study¹ included subjects with mild symptomatology, albeit symptoms not from travel or hypochondriasis, as was shown by the paucity of these symptoms in the sea-level control group. If our definition of acute mountain sickness had required disabling symptoms needing medication, the incidence would be 12%, about what Dr Houston predicts. As noted in the article,² the even higher incidence in the placebo group of the dexamethasone treatment study is probably a consequence of selection, as subjects with a history of a disease are more likely to enter a drug trial. Perhaps more important than "accurate epidemiologic" research is a consensus on the nomenclature of the altitude-related