title: Symptom structure of acute mania: a factor study of the 24-item Brief Psychiatric Rating Scale in a national sample of patients hospitalized for a manic episode.
abstract: BACKGROUND
  Despite increasing interest in dimensional psychopathology and the use of symptom clusters in clinical research, factor analytic studies of mania are rare. Most studies included not only manic patients, but also patients with a mixed episode or other severe mental disorders. We aimed at further elucidating the symptom structure of manic states.
  
  
  METHODS
  As part of a national survey of acute psychiatric inpatient care, all patients admitted to a random sample of Italian public and private facilities during an index period underwent a standardized assessment, including the 24-item Brief Psychiatric Rating Scale (BPRS-24). Eighty-eight patients (90% of all manic patients admitted) with an ICD-10 diagnosis of Bipolar Affective Disorder, Current Episode Manic with complete data were included in this study. Principal axis factor analysis with Varimax rotation was performed on BPRS-24 items.
  
  
  RESULTS
  Four factors were extracted, explaining 51% of total variance. They were interpreted as Mania, Disorganization, Positive Symptoms, and Dysphoria. The distribution of the Disorganization factor was positively skewed, with most patients relatively free from disorganization symptoms and some patients showing varying degrees of severity.
  
  
  CONCLUSIONS
  The sample size was relatively small; also, patients were not administered a structured diagnostic interview. However, reasonably large samples are usually sufficient when communalities are high. Also, the manic episode is a clear-cut diagnostic entity easily identified by experienced clinicians, and the independent BPRS-24 ratings corroborated the diagnosis.
  
  
  CONCLUSIONS
  The identification of a Mania, Positive Symptoms, and Dysphoria factor is consistent with most previous studies. The identification of a Disorganization factor in a sample including only manic patients is a new finding that may have clinical implications, as its distribution suggests the possibility of distinguishing two patient groups, which may require different interventions to achieve optimal therapeutic response. The factorially derived BPRS-24 subscales may be useful for evaluation of treatment effects in clinical trials of antimanic agents.
authors.affiliation: Italian National Institute of Health, Center of Epidemiology, Surveillance and Health Promotion, Mental Health Unit, Viale Regina Elena, 299 - 00161 Rome, Italy. angelo.picardi@iss.it
authors.forename: Angelo
authors.initials: A
authors.lastname: Picardi
authors.forename: Francesca
authors.initials: F
authors.lastname: Battisti
authors.forename: Giovanni
authors.initials: G
authors.lastname: de Girolamo
authors.forename: Pierluigi
authors.initials: P
authors.lastname: Morosini
authors.forename: Bruno
authors.initials: B
authors.lastname: Norcio
authors.forename: Renata
authors.initials: R
authors.lastname: Bracco
authors.forename: Massimo
authors.initials: M
authors.lastname: Biondi
mesh_terms: D000328:Adult; D001714:Bipolar Disorder / Q000175:diagnosis* / Q000453:epidemiology / Q000523:psychology; D010054:Brief Psychiatric Rating Scale / Q000706:statistics & numerical data*; D003430:Cross-Sectional Studies; D005260:Female; D006306:Health Surveys; D006760:Hospitalization / Q000706:statistics & numerical data*; D006801:Humans; D007558:Italy; D007902:Length of Stay / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D011594:Psychometrics / Q000706:statistics & numerical data; D012959:Socioeconomic Factors