Sleep-wake complaints in patients with sleep-related respiratory disturbances.

The relation of sleep complaint to sleep continuity and respiratory disturbance was studied by comparing 2 series of patients with sleep apnea, one group complaining of insomnia and the other of excessive daytime sleepiness. On polysomnographic evaluation, patients with insomnia complaints had fewer and shorter, primarily central, apneas that had little hypoxemic effects. Patients with excessive sleepiness complaints had more and longer, primarily obstructive, apneas that produced significant hypoxemia. Sleep of the excessively sleepy patients was lighter and longer, whereas that of the patients with insomnia was characterized by more wake time before and after sleep onset. The excessively sleepy patients were objectively sleepy on a test of daytime sleepiness, whereas patients with insomnia were alert.