Moderate carbon monoxide exposure during sleep: neuro- and psychophysiological effects in young and elderly people.
In order to assess age-related effects of carbon monoxide (CO) on brain wave-activity and sleep, auditory evoked potentials (AEP) were measured during sleep in 10 healthy young volunteers (20-25 years) and in a group (N = 10) of healthy elderly Ss (55-72 years) under control- and exposure-conditions in counterbalanced order. Sleep-stages were classified according to the Rechtschaffen and Kales scoring-system. In addition to electrophysiological measures memory-performance and subjective feeling (mood-scale) was assessed before and after sleep. Eight hours of CO-exposure (100 ppm) gave rise to about 8% COHb. In the group of young Ss there was a significant (p less than 0.05) increase of deep sleep (stages 3,4), and a decrease of stage REM-sleep during CO-exposure, whereas in elderly Ss similar but non-significant sleep-changes occurred. Some CO-related AEP-changes within different sleep-stages, namely shorter latencies in elderly Ss and higher amplitudes in young Ss, approached significance. Within the group of young Ss there was a tendency to more depressed mood after CO-exposure, as well as to CO-related impairment of memory consolidation; no such effects were observed in elderly Ss. The general hypothesis of more pronounced CO-susceptibility of elderly people was, therefore, not supported in this study.
D000328:Adult; D000375:Aging; D001921:Brain / Q000187:drug effects*; D002248:Carbon Monoxide / Q000494:pharmacology*; D002263:Carboxyhemoglobin / Q000378:metabolism; D004569:Electroencephalography; D005071:Evoked Potentials / Q000187:drug effects; D006801:Humans; D008297:Male; D008568:Memory / Q000187:drug effects; D012890:Sleep / Q000187:drug effects*; D012894:Sleep Stages / Q000187:drug effects
D002248:Carbon Monoxide; D002263:Carboxyhemoglobin