[Study of the relation between disorders of nocturnal respiratory rhythm and hypersomnia].

Sleep and respiration were recorded during two consecutive nights in 15 normal subjects, 18 patients suffering from narcolepsy and 9 with non-cataplectic hypersomnia. The normal subjects showed episodes of central apnea, the degree of which increased with age and periodic respiration. In both categories of hypersomniacs, the patients were divided into three groups according to the severity of disturbances in nocturnal respiratory rhythm:--group 1: identical to the normal subjects,--group 2: moderate qualitative or quantitative abnormalities,--group 3: presence of a large number of episodes of obstructive apnea. On the basis of these results, it was concluded that disturbances in nocturnal respiratory rhythm are not specific for any particular type of hypersomnia, nor were they the main cause of hypersomnia when present to a large extent, but that obstructive apnea could be an aggravating factor.