Incidence and predictors of severe altitude illness symptoms in Mt. Kilimanjaro hikers: a prospective cohort study

Abstract

Background: Each year several Mt. Kilimanjaro hikers die due to altitude illness although urgent descent is technically easily possible. The objectives of this study were to determine the incidence and predictors of severe altitude illness symptoms and of summit success in Mt. Kilimanjaro hikers, and the measures taken when altitude illness symptoms develop. Methods: A prospective observational cohort study in Mt. Kilimanjaro hikers was conducted from December 2019 until March 2020. Participants were asked to complete a questionnaire at the entrance gate and one at the descend gate. A multivariate logistic regression was performed to study the relations between the variables. Results: A total of 1237 recreational hikers and 266 porters or guides were included. The incidence of severe symptoms was 8.6% in recreational hikers and 1.5% in porters and guides. One percent (1.1%) of hikers was hospitalized due to severe altitude illness. A history of severe altitude illness, young age, summit failure and lack of clear advice predicted the development of severe symptoms. Uhuru peak was reached by 87.9% of the hikers. Absence of severe symptoms, acetazolamide prophylaxis, climbing higher in daytime, young age and climbing in more days predicted summit success. The majority climbed further despite the presence of mild or severe symptoms. The only measure taken in case of mild symptoms that was associated with a lower incidence of severe symptoms was not climbing further. Conclusion: The incidence of severe altitude illness symptoms in Mt. Kilimanjaro hikers was observed to be high. However, how hikers reacted during symptoms was not appropriate. Therefore, travel health counselors should emphasize even more that hikers do not ascend higher until mild symptoms have resolved and that it is vital to descend immediately when severe symptoms develop. In addition, they can be informed on the measures which improved summit success.

Review of the relationship and underlying mechanisms between the Qinghai–Tibet plateau and host intestinal flora

“…High-altitude regions have low oxygen, extreme cold temperatures, and high radiation levels, all of which having a profound impact on the structure and function of the intestinal flora. The Qinghai–Tibet Plateau in China is the largest plateau area in the world, and visitors experience symptoms of discomfort, especially headache, chest tightness, nausea, and vomiting ( Wen et al, 2014 ; Croughs et al, 2022 ). Kleessen et al (2005) reported that dysbiosis, in which pathogenic bacteria increase and probiotics decrease, often occurs in plateau populations.…”

Examination of novel diagnostic approaches and contemporary strategies for preventing acute mountain sickness

“…Therefore, allowing ample time for recovery and acclimatization is pivotal for safety at high altitudes (34,39,41). The primary treatment for severe altitude sickness revolves around rapid descent from high altitudes, coupled with oxygen therapy.…”

“…The primary treatment for severe altitude sickness revolves around rapid descent from high altitudes, coupled with oxygen therapy. Additionally, medications like acetazolamide, dexamethasone, and nifedipine might be considered as part of the treatment protocol (34).…”

“…Intriguingly, observations reveal that at 3500 meters above sea level, over a quarter of individuals contend with acute altitude sickness, a percentage that dramatically escalates to over half of individuals at the formidable altitude of 6000 meters above sea level (37,39). As an example, among tourists scaling the renowned Kilimanjaro, approximately 47-86% grapple with acute mountain sickness, and the mortality rate stands at an estimated 1 in 4350 climbers (34).…”

Strengthening Altitude Knowledge: A Delphi Study to Define Minimum Knowledge of Altitude Illness for Laypersons Traveling to High Altitude

“…Epidemiological studies have shown that poor knowledge is accompanied by an increased risk of altitude illness, while greater knowledge is associated with a lower incidence of altitude illness. (Croughs et al , 2022;Gaillard et al , 2004;Hackett et al , 1976;Kayser, 1991;McDevitt et al , 2014;Shlim and Gallie J, 1992) Although a lack of knowledge may affect the risk of developing acute altitude illness, no resources have defined the appropriate baseline level of knowledge about high-altitude physiology and medicine for laypersons traveling to high altitude. The overwhelming majority of consensus statements and guidelines are intended for healthcare professionals, trekking or expedition leaders, or mountain guides (Kupper, 2020;Kupper et al , 2012) and do not specifically target laypersons.…”