chronic mountain sickness

n.
  1. Altitude sickness that occurs despite acclimatization to high altitudes, characterized by high levels of circulating red blood cells, hypoxemia, and reduced mental and physical capacity.Monge's disease
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.