Memory impairment associated with chronic hypoxia.

A series of mental tests was administered to a group of patients who were chronically hypoxic as a result of chronic obstructive lung disease. The oxygen tension from arterialised ear lobe blood samples was correlated with scores on the mental tests. Hypoxia had a significant effect on the results of memory tests but not on the results of other tests of mental function. The same pattern of results has been reported in hypoxic animals. This finding has implications for the treatment of chronic hypoxia--including the very mild hypoxia that is relatively common in the elderly; if this were treated possibly memory impairment would no longer be an inevitable accompaniment of aging.