Altitude sickness becomes two diseases

Mountaineers often contract altitude sickness – but a new study suggests there are two separate illnesses that afflict them.

One form of altitude sickness causes sleep disruption while a second form tends to cause headaches, according to researchers at Edinburgh University, UK.

The researchers at the university’s Roislin Institute studied people with experience of high altitudes in the Andes in Bolivia and at Mount Kilimanjaro in Tanzania.

They used genetic analysis to study patterns of symptoms of some 292 climbers on expeditions.

They have reported their findings in the journal PLOS One.

The researchers say their findings should help with the development of improved treatments.

Researcher Dr Ken Baillie said: "For more than two decades we have thought of altitude sickness as a single disease.

"We have now shown that it is at least two separate syndromes that happen to occur in the same people at a similar time.

Studying these syndromes in isolation will make it easier to understand the cause of each one, and to test new treatments."

PLOS One 22 January 2014; doi: 10.1371/journal.pone.0081229 [abstract]