Mania often leads to a feeling of being refreshed after only 3-4 h of sleep at night. It may even prevent sleep for several days, but the subject then becomes exhausted. The total sleep time is shortened, sleep latency is prolonged, there is a short REM sleep latency, the duration of stages 3 and 4 NREM sleep is often normal, but there can be a gross alteration in the sleep architecture. Abnormalities of circadian rhythms include changes in the diurnal cortisol secretion pattern.
Sleep deprivation tends to elevate the mood, as in depression, and this may worsen the mania and lead to further sleep restriction. Treatment with benzodi-azepines or sedating antipsychotics improves the insomnia in bipolar disorder. This also improves with lithium, but more slowly.
Excessive daytime sleepiness only occurs in the depressive phase of bipolar illnesses.
Was this article helpful?