The cerebral effects of ascent to high altitudes

Lancet Neurol. 2009 Feb;8(2):175-91. doi: 10.1016/S1474-4422(09)70014-6.


Cellular hypoxia is the common final pathway of brain injury that occurs not just after asphyxia, but also when cerebral perfusion is impaired directly (eg, embolic stroke) or indirectly (eg, raised intracranial pressure after head injury). We Review recent advances in the understanding of neurological clinical syndromes that occur on exposure to high altitudes, including high altitude headache (HAH), acute mountain sickness (AMS), and high altitude cerebral oedema (HACE), and the genetics, molecular mechanisms, and physiology that underpin them. We also present the vasogenic and cytotoxic bases for HACE and explore venous hypertension as a possible contributory factor. Although the factors that control susceptibility to HACE are poorly understood, the effects of exposure to altitude (and thus hypobaric hypoxia) might provide a reproducible model for the study of cerebral cellular hypoxia in healthy individuals. The effects of hypobaric hypoxia might also provide new insights into the understanding of hypoxia in the clinical setting.

Publication types

  • Review

MeSH terms

  • Adult
  • Air Pressure
  • Altitude Sickness / drug therapy
  • Altitude Sickness / genetics
  • Altitude Sickness / physiopathology*
  • Altitude Sickness / psychology
  • Brain Edema / etiology
  • Brain Edema / physiopathology
  • Cerebrovascular Circulation / physiology*
  • Child
  • Chronic Disease
  • Headache / etiology
  • Headache / physiopathology
  • Humans
  • Hypoxia / physiopathology
  • Psychomotor Performance / physiology