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Dizzy heights of popular peak pose real risks for climbers

The increasing number of climbers scaling Africa's highest peak need to be made more aware of the risks associated with high altitude, researchers warn.

The increasing number of climbers scaling Africa's highest peak need to be made more aware of the risks associated with high altitude, researchers warn.

University of Edinburgh researchers, including Kenneth Baillie, who undertakes research at The Roslin Institute, tested levels of altitude sickness among more than 200 climbers ascending Kilimanjaro.

They found that many of the climbers were taking unnecessary risks at high altitude by failing to acclimatise. This can lead to altitude sickness, which is potentially fatal.

Almost half of the climbers studied were suffering from altitude sickness, which can occur above 2,500 metres and is caused by climbing too fast. Symptoms can include headaches, fatigue, and sleep disturbance.

Last year more than 25,000 climbers scaled Mount  Kilimanjaro, which has become a popular destination among novice climbers. The mountain's profile was also raised last year with a celebrity Comic Relief charity climb.

The peak, at 5,895 metres, is the world's highest free-standing mountain. Most people have no exposure to high altitude before making their ascent because the mountain's base is only 1,860 metres above sea level.

In severe instances altitude sickness can lead to potentially fatal conditions such as high altitude pulmonary oedema - fluid accumulating in the lungs - and high altitude cerebral oedema - fluid build-up in the brain.

Researchers have also published some new advice about how to climb safely and avoid altitude sickness:

Scientists camped at 4,730 metres on the mountain for three weeks and studied climbers for symptoms of altitude sickness. They found that during the steep ascent, neither altitude sickness drugs nor a rest day during the climb had a major effect against altitude sickness. They concluded that climbers were going up so steeply that drugs cannot protect against the harmful effects of the altitude.

However, the research found that climbers who had managed to acclimatise prior to the climb were less likely to suffer from altitude sickness. Opportunities for such acclimatisation can be found on Mount Meru, which at 4,566 metres is located conveniently close to Mount  Kilimanjaro.

The study is published in the journal High Altitude Medicine and Biology.

We found that many climbers knew little or nothing about altitude sickness, and did not have previous experience of being at high altitude. This research emphasises the need to increase awareness of the risks of altitude sickness and the importance of taking your time to acclimatise. Undertaking an acclimatisation trek before attempting the summit of Mount Kilimanjaro offers climbers the best chance of a safe, successful summit.

Dr Stewart JacksonResearch conductor


Anyone planning to climb at high altitude should be aware of the risks involved. Altitude sickness is often easy to avoid if you recognise the symptoms early, but these data suggest that many people continue to climb higher despite the danger signs.

Kenneth BaillieResearch supervisor


For more information please contact

Tara Womersley

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