A retrospective study of acute mountain sickness on Mt. Kilimanjaro using trekking company data.

BACKGROUND

High altitude illnesses (HAI) are a risk factor for any individual who is exposed to a significant increase in altitude. To learn more about the epidemiology of HAI, we sought to determine if health records from a commercial trekking company could provide novel data on the prevalence of HAI, as well as efficacy data regarding common HAI therapeutics.

METHODS

Health parameters from 917 tourists ascending Mt. Kilimanjaro over a 10-yr period were analyzed for meaningful data.

RESULTS

Of all subjects, 70% experienced at least one instance of a symptom related to HAI (headache, nausea, vomiting, diarrhea, or loss of appetite) during the trek. Acetazolamide was used at least once by 90% of subjects and, of those who used acetazolamide, 92% began taking it on day 1 of the ascent. Acetazolamide was found to improve oxygen saturation 1.2% above 9842.5 ft (3000 m). Dexamethasone use 12 h prior to ascending above 18,996 ft (5790 m) decreased the probability of a subject exhibiting at least one AMS symptom at that altitude.

DISCUSSION: The prevalence of AMS symptoms was not reduced by taking 2 extra days to reach the summit of Mt. Kilimanjaro. Prophylactic acetazolamide modestly improved oxygen saturation; however, it did not reduce symptoms. Therapeutic dexamethasone, especially at higher altitudes, was effective at reducing symptoms. We conclude that meaningful high altitude physiological data can be obtained from private trekking companies.