Many bodily functions can be impacted by high-altitude and low-oxygen environments, especially sleep. High-quality sleep is crucial for mood, memory, and overall health and well-being. When sleep is consistently disrupted, troubles with focus, stress, problem-solving, and energy can arise. High-altitude environments can cause several health conditions including nausea and confusion as well as acute mountain sickness, characterized by headache, fatigue, weakness, and gastrointestinal symptoms.
How Does High Altitude Impact Sleep?
High altitudes impact both sleep quality and sleep quantity and can negatively affect sleep in two ways: by altering breathing patterns and by disrupting the stages of sleep. Dr. Michael Furian, a senior researcher at the University of Zürich, helped us understand these disruptions and how to mitigate them.
Sleep Quality At higher altitudes, there is less oxygen in the blood. To compensate, we begin to breathe quickly (or hyperventilate). Hyperventilation leads to decreased carbon dioxide (CO2) levels within our blood. Our bodies need a certain amount of CO2 to function properly, so when CO2 levels drop too low, we stop breathing for 15 to 20 seconds. This allows CO2 to build back up to normal levels, and we can breathe again, causing high-altitude periodic breathing. This is a type of sleep-disordered breathing characterized by repeated central sleep apneas, which is associated with daytime sleepiness, headaches, and poor mood. Anyone who ascends to 4,000 meters (about 13,120 feet) or above will likely experience this condition to a certain degree.
Sleep Quantity High altitude is associated with less deep sleep, increased superficial sleep, and more disruption throughout the night. Superficial sleep is crucial to ensure the overall length of sleep, but the lack of deep sleep is associated with fatigue, memory problems, and decreased focus.
Who Does High Altitude Affect?
Anyone can be impacted by altitude-related conditions; however, some populations are at greater risk than others. Men.
Men. are more likely to have high[1]altitude periodic breathing since they have a stronger stimulus for hyperventilation at high altitudes. Conversely, men generally have less acute mountain sickness than women.
Individuals with Respiratory Disease. Individuals with pre-existing conditions, such as chronic obstructive pulmonary disease (COPD), obstructive sleep apnea, or other lung diseases, are at greater risk for experiencing intense altitude-related sleep disturbances. Anyone with sleep disturbances at low altitudes will see them increase at high altitudes.
How to Prevent Altitude-Related Sleep Disturbances
Worried about altitude-related conditions?
Fortunately, preventive measures can be taken.
Prescription Medication. Acetazolamide, a prescription medication, is a preventative treatment against acute mountain sickness and has been shown to stabilize breathing and decrease high altitude periodic breathing. It can also increase a person’s ability to adapt to the elevation more quickly and with less discomfort.
Avoid Alcohol. Avoiding alcohol at greater altitudes can help to prevent sleep disturbances.
Avoid Rigorous Exercise. Perform light exercise rather than moderate or heavy exercise. High-intensity training is a risk factor for developing symptoms of acute mountain sickness and exaggerate disturbed sleep.
Slowly Ascend. Allow your body time to slowly adjust to greater altitudes to decrease the likelihood of suffering from sleep disturbances and altitude-related illnesses. Spending multiple days at a certain altitude before ascending is associated with less sleep disruption.
*Citations available on healthiersleepmag.com
Grayson Vidovich is an occupational therapist who specializes in health promotion and disease prevention.