Periodic movements during sleep, sleep fragmentation, and sleep-wake complaints.

To better understand the relation of sleep complaint to sleep continuity and periodic movements during sleep (PMS), two groups of patients were studied retrospectively. One group of 51 patients, 26 men and 25 women, with a mean age of 56.4 years, complained of insomnia. The other group of 29 patients, 20 men and nine women, with a mean age of 55.8 years, complained of excessive daytime sleepiness. Sleepy patients differed significantly from insomnia patients in that they fell asleep faster and slept longer. They showed more frequent arousals (shifts to stage 1 sleep and number of awakenings) than insomnia patients who had longer arousals (mean duration of awakenings). Insomnia patients had more series of PMS, but sleepy patients had more PMS bursts per series.