Neuropsychological outcomes of nocturnal asthma

In spite of frequent reports that nocturnal asthma results in fatigue and i mpaired cognitive performance, there exists little objective evidence as to the daytime consequences of this disorder. Treatment studies have establis hed that the symptoms of nocturnal asthma improve with medication intervent ion, but performance does not. Studies of obstructive sleep apnea (OSA), a source of generally more severe sleep fragmentation, have demonstrated that measurement of sleep-deprivation effects is limited to tasks requiring hei ghtened alertness and rapid information processing, and that the degree of score change is related to the degree of sleep disruption. Studies of norma l, but sleep-deprived, subjects indicate that (1) utilization of repetitive measures sustained for long duration can potentiate motivation to overcome the effects of fatigue in the laboratory, and (2) even when average scores do not change significantly, performance becomes more irregular. These col lective findings about the measurement of performance impairment secondary to sleep deprivation can be used to guide new studies of nocturnal asthma. Finally, children must be included in future investigations because they ma y be at even greater risk for daytime consequences of nocturnal asthma than adults.