Apneic and nonapneic breathing disorders in sleep.

Recent research has demonstrated that respiratory activities are stage dependent and that some breathing disorders appear only in sleep. Sleep apnea syndromes, defined as the occurrence of at least 30 apneas of greater than or equal to 10 sec, dramatically affect patients' sleep and waking behavior. During 1977-80, 114 patients with sleep apnea and 82 patients with nonapneic breathing disorders in sleep, were recorded in the Technion Sleep Laboratory. In both groups, patients were mostly male in the 30- to 50-yr age-group, whose primary complaint was excessive daytime sleepiness. Nonapneic breathing disorders in sleep included periodic breathing, periodic hyperpnea, and variations in rate of breathing without notable changes in volume. It is suggested that some of the patients with sleep apnea syndrome and with non-apneic breathing disorders in sleep belong to the same etiological group, each representing a different stage along a single continuum of breathing disorders.