Sleep patterns of asthmatic children: All-night electroencephalographic studies

Ten asthmatic children were studied for 25 nights with electroencephalogram, electromyogram, and eye movements continuously recorded. Twenty asthmatio episodes were recorded. No incidents were observed in the first third of the night when Stages 3 and 4 sleep (deep sleep) predominated. Ten incidents were noted in each of the second and last thirds of the night. There were no clear-cut relationships between asthmatic attacks and occurrence of REM sleep. Of the 20 asthmatic episodes, 5 occurred from REM sleep; this was proportionate to the percentage time the children spent in this sleep stage. In comparison to normal children of the same ages, the asthmatic children had a significant reduction in Stage 4 sleep and, as expected, frequent awakenings and a significant decrease in the time spent asleep. The decrease in incidents in Stage 4 sleep may be due to a lessening in respiratory difficulty during this sleep stage. Another possibility is that respiratory difficulty exists in the same degree throughout the night, but, because of the depth of sleep during this sleep phase, the child does not respond to the disturbing stimulus.