Altitude

Altitude sickness can mimic the symptoms of sleep apnea, and aggravate the symptoms of sufferers of sleep apnea. Altitude above 7500 feet will affect 25% of people, including otherwise healthy and even athletic individuals. While most people naturally acclimate in a period of days or weeks, some individuals remain affected by altitude as long as they remain above 7500 feet.

If you experience headaches, sleeplessness, confusion, dizziness, breathlessness and similar symptoms at altitudes above 7000 feed, you may be suffering from Acute Mountain Sickness (AMS). The most recognized treatment for high altitude is Diamox (acetazolamide), which can be taken at the direction of your doctor before you arrive at high altitude. Please read this article for more information on Acute Mountain Sickness[1]. High altitude can present many problems for certain people that a CPAP machine cannot compensate for [2]. Be aware that sedatives and sleep medications can make AMS worse, especially for people that suffer from sleep apnea, because those drugs cause Cheyne-Stokes respiration at high altitude.

Acute mountain sickness is a constellation of disorders caused by acute exposure to low pressure and low oxygen levels. It appears to be caused by swelling of the brain- a mild form of HACE (see below). Diagnosis (by the Lake Louise Criteria, which were formulated at the Hypoxia Symposium there a number of years ago) requires the presence of headache and one or more of the following:

   * GI symptoms (nausea, loss of appetite)
   * Fatigue or weakness
   * dizziness or lightheadedness
   * difficulty sleeping

A large study in Colorado found that 25% of people from low altitude ascending rapidly and sleeping at 8200ft (2500m) will develop AMS. These people may feel lousy for short while, but most of them will get better in a few days and not get sicker. About 1%, however, will develop more severe illness- high altitude cerebral edema (HACE, or brain swelling) or high altitude pulmonary edema (HAPE, or high blood pressure and fluid in the lungs). Both of these are life-threatening emergencies, and require immediate medical attention and descent if at all possible. For most people who suffer AMS (but not HACE), significant relief from symptoms is possible with treatment using Diamox and ensuring good hydration, limiting exertion and avoiding alcohol.

Reference the following forum pages to see how this has affected a forum member living at 8000 feet. [3] [4]