‘Altitude Sickness’ Might Actually Be Two Different Diseases

Something like 20% of people in the United States who travel to the mountains in the west report getting altitude sickness, but the symptoms might actually be from two different diseases

Image: Suzy Glass

As you get higher and higher in elevation, some percentage of people start to feel dizzy and get headaches. Sometimes they can’t sleep. It’s not uncommon—something like 20 percent of people in the United States who travel to the mountains in the west report getting altitude sickness. But a recent analysis showed that perhaps altitude sickness might not be as simple as once thought. It might be two entirely different problems.

Researchers discovered this by applying network theory to medicine, analyzing the correlations between symptoms from a sample of 300 people traveling to high altitudes. When they then mapped those symptoms as a network, they suddenly saw three very different patterns. The strongest difference was that headaches and sleep disturbances didn’t necessarily go together, according to Technology Review:

That’s an interesting result that also makes medical sense. There is mounting evidence that headaches and sleep disturbances are caused by different mechanisms. For example, headaches in those suffering from altitude sickness seem to be caused by factors such as fluid retention and tissue swelling in the brain.  Sleep disturbance, on the other hand, seems to be related to breathing problems.

It’s becoming more common in medicine to use network theory to tease apart the associations between symptoms, diseases and causes. Networks can be applied to epidemiology and pharmacology, for instance, indicating where diseases will spread and how drugs interact in the body.

When it comes to altitude sickness, the network framework can help doctors reconsider what was once common knowledge. The network can’t, however, tell them what the biological differences are between these two seemingly different altitude-related issues. For that, we still need real, live scientists to study the problem.

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