title: Interictal psychotic episodes in epilepsy: duration and associated clinical factors.
abstract: OBJECTIVE
  There have been few reports showing the distribution of the duration of interictal psychosis (IIP) episodes and their association with clinical characteristics. To clarify the nature of IIP, we studied the duration of IIP episodes and their related factors.
  
  
  METHODS
  One hundred fifty-five patients with epilepsy exhibited 320 IIP episodes during our follow-up period (mean 16.9 years). The duration of all the episodes and the longest episode in each patient during the follow-up periods were studied. Characteristics of the patients (e.g., epilepsy type, age of onset, and family history of psychosis) and episode-specific factors (e.g., age of the episode, seizure frequency, administrations of antiepileptic drugs [AEDs] and antipsychotic drugs [APDs]) were analyzed in association with the duration of the episodes.
  
  
  RESULTS
  Mean duration of the 320 IIP episodes was 82.7 weeks and that of the longest IIP episodes was 150.1 weeks. During the follow-up period, 17 patients (11.0%) showed all episodes remitting within a month and 54 (34.8%) showed all episodes lasting for 6 months or longer. The IIP episodes that occurred at a younger age were often prolonged. Patients with a family history of psychosis or with early onset of psychosis tended to have more prolonged IIP episodes. Among the episodes treated with APDs, early administration of APDs was significantly associated with shorter IIP duration.
  
  
  CONCLUSIONS
  The distribution of the duration of IIP episodes indicated the broad spectrum and heterogeneity of the IIP phenomena. The individual vulnerability to psychosis may be associated with prolonged episodes. Administration of APDs soon after onset of the episodes appeared to be effective in controlling them. These findings support empirical treatment principles for IIP to administer APDs at an early stage of its development.
authors.affiliation: Adachi Mental Clinic, Sapporo, Japan. adacchan@tky2.3web.ne.jp
authors.forename: Naoto
authors.initials: N
authors.lastname: Adachi
authors.forename: Nozomi
authors.initials: N
authors.lastname: Akanuma
authors.forename: Masumi
authors.initials: M
authors.lastname: Ito
authors.forename: Mitsutoshi
authors.initials: M
authors.lastname: Okazaki
authors.forename: Masaaki
authors.initials: M
authors.lastname: Kato
authors.forename: Teiichi
authors.initials: T
authors.lastname: Onuma
mesh_terms: D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D000927:Anticonvulsants / Q000627:therapeutic use; D014150:Antipsychotic Agents / Q000627:therapeutic use*; D002648:Child; D004569:Electroencephalography; D004827:Epilepsy / Q000150:complications* / Q000188:drug therapy*; D005260:Female; D006801:Humans; D007223:Infant; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales; D011618:Psychotic Disorders / Q000150:complications* / Q000188:drug therapy*; D012189:Retrospective Studies; D012307:Risk Factors; D055815:Young Adult
chemical_list: D000927:Anticonvulsants; D014150:Antipsychotic Agents