title: Sleep propensity at daytime as assessed by Multiple Sleep Latency Tests (MSLT) in patients with schizophrenia increases with clozapine and olanzapine.
abstract: Sleep propensity at daytime has not been investigated in untreated patients with schizophrenia. Furthermore, while the antipsychotics clozapine and olanzapine are considered to frequently cause 'sleepiness' or 'sedation', this has not been objectified yet. Therefore, 30 patients with schizophrenia were included in this randomized, double-blind study. Sleep propensity was assessed before and after 2, 4 and 6 weeks of treatment with either clozapine or olanzapine using a Multiple Sleep Latency Test (MSLT); in the MSLT, sleep latencies of 5 nap opportunities of 20 min during daytime are averaged. In addition, the number of sleep onsets was recorded. Mean sleep latency in untreated schizophrenic patients was 16.2 ± 0.8 min at baseline. Both antipsychotics induced an increase of sleep propensity as indicated by a shortened sleep latency and more sleep onsets during the treatment period as compared to baseline. These effects were strongest in the morning. Four patients receiving clozapine and 3 patients receiving olanzapine reported subjective sleepiness, in all but one commencing in the first treatment week and persisting until study end. While the mean sleep latency during treatment was significantly shorter in these patients (12.3 ± 0.8 min) than in those without subjective sleepiness (14.9 ± 0.7 min), a short sleep latency was not necessarily associated with subjective sleepiness. In conclusion, mean sleep latency was >36% longer (i.e. sleep propensity was lower) in untreated patients with schizophrenia than in healthy subjects previously consistently reported. Furthermore, clozapine and olanzapine increased sleep propensity in schizophrenic patients. A minority of patients reported subjective sleepiness.
authors.affiliation: Department of Psychiatry and Psychotherapy, University of Leipzig, Leipzig, Germany. Michael.Kluge@medizin.uni-leipzig.de
authors.forename: Michael
authors.initials: M
authors.lastname: Kluge
authors.forename: Hubertus
authors.initials: H
authors.lastname: Himmerich
authors.forename: Peter M
authors.initials: PM
authors.lastname: Wehmeier
authors.forename: Christine
authors.initials: C
authors.lastname: Rummel-Kluge
authors.forename: Mira
authors.initials: M
authors.lastname: Dalal
authors.forename: Dunja
authors.initials: D
authors.lastname: Hinze-Selch
authors.forename: Thomas
authors.initials: T
authors.lastname: Kraus
authors.forename: Ralf W
authors.initials: RW
authors.lastname: Dittmann
authors.forename: Thomas
authors.initials: T
authors.lastname: Pollmächer
authors.forename: Andreas
authors.initials: A
authors.lastname: Schuld
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D014150:Antipsychotic Agents / Q000627:therapeutic use*; D001569:Benzodiazepines / Q000627:therapeutic use*; D003024:Clozapine / Q000627:therapeutic use*; D006970:Disorders of Excessive Somnolence / Q000188:drug therapy* / Q000209:etiology; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D000077152:Olanzapine; D017286:Polysomnography; D011569:Psychiatric Status Rating Scales; D011930:Reaction Time / Q000187:drug effects; D012559:Schizophrenia / Q000150:complications / Q000188:drug therapy*; D012894:Sleep Stages / Q000187:drug effects; D013223:Statistics as Topic; D013997:Time Factors; D055815:Young Adult
chemical_list: D014150:Antipsychotic Agents; D001569:Benzodiazepines; D003024:Clozapine; D000077152:Olanzapine