Sleep Disorders in Schizophrenia. A Review of Literature

Up to 80% of patients with schizophrenia have suffered from sleep disorders (SD), which are normally under diagnosed and undertreated due to lack of consideration in the management of schizophrenia. The most common sleep disorders in schizophrenia are insomnia, restless leg syndrome (RLS), obstructive sleep apnea syndrome (OSAS), hypersomnia, parasomnia and circadian rhythm disorders. The relevance of insomnia should be emphasized, as it can be a prodromal signof schizophrenia, as well as an alarm sign of an incipient psychotic decompensation. Additionally, the clinical recovery of a psychotic process is usually correlated with sleep normalization. Multiple polysomnographic disturbances on sleep architecture have been found in patients with schizophrenia, including increased sleep latency, awakenings during sleep, sleep-wake cycle inversion, as well as poor sleep efficiency. These objective disturbances have been correlated to subjective poor sleep quality and other main clinical symptoms in schizophrenia.