title: Subtyping depression in the medically ill by cluster analysis.
abstract: BACKGROUND
  There is increasing awareness of the need of subtyping major depressive disorder, particularly in the setting of medical disease. The aim of this investigation was to use both DSM-IV comorbidity and the Diagnostic Criteria for Psychosomatic Research (DCPR) for characterizing depression in the medically ill.
  
  
  METHODS
  1700 patients were recruited from 8 medical centers in the Italian Health System and 1560 agreed to participate. They all underwent a cross-sectional assessment with DSM-IV and DCPR structured interviews. 198 patients (12.7%) received a diagnosis of major depressive disorder. Data were submitted to cluster analysis.
  
  
  RESULTS
  Two clusters were identified: depressed somatizers and irritable/anxious depression. The somatizer cluster included 58.6% of the cases and was characterized by DCPR somatization syndromes (persistent somatization, functional somatic symptoms secondary to a psychiatric disorder, conversion symptoms, and anniversary reactions) and DCPR alexithymia. The anxious/irritable cluster had 41.4% of the total sample and included DCPR irritable mood and type A behavior and DSM-IV anxiety disorders.
  
  
  CONCLUSIONS
  The study has limitations due to its cross-sectional nature. Further, these findings require additional validation in another sample.
  
  
  CONCLUSIONS
  The findings indicate the need of expanding clinical assessment in the medically ill to include the various manifestations of somatization, irritable mood, type A behavior and alexithymia, as encompassed by the DCPR. Subtyping major depressive disorder may yield improved targets for psychosomatic research and treatment trials.
authors: Laboratory of Psychosomatics and Clinimetrics, Department of Psychology, University of Bologna, Bologna, Italy. jenny.guidi2@unibo.it
authors: Jenny
authors: J
authors: Guidi
authors: Giovanni A
authors: GA
authors: Fava
authors: Angelo
authors: A
authors: Picardi
authors: Piero
authors: P
authors: Porcelli
authors: Antonello
authors: A
authors: Bellomo
authors: Silvana
authors: S
authors: Grandi
authors: Luigi
authors: L
authors: Grassi
authors: Paolo
authors: P
authors: Pasquini
authors: Roberto
authors: R
authors: Quartesan
authors: Chiara
authors: C
authors: Rafanelli
authors: Marco
authors: M
authors: Rigatelli
authors: Nicoletta
authors: N
authors: Sonino
mesh_terms: D000275:Adjustment Disorders / Q000175:diagnosis / Q000453:epidemiology / Q000523:psychology; D000328:Adult; D000342:Affective Symptoms / Q000175:diagnosis / Q000523:psychology; D000368:Aged; D001008:Anxiety Disorders / Q000175:diagnosis / Q000453:epidemiology* / Q000523:psychology; D002908:Chronic Disease / Q000523:psychology*; D016000:Cluster Analysis; D015897:Comorbidity; D003863:Depression; D003865:Major Depressive Disorder / Q000175:diagnosis / Q000453:epidemiology* / Q000523:psychology; D039721:Diagnostic and Statistical Manual of Mental Disorders; D005260:Female; D006304:Health Status; D006801:Humans; D007508:Irritable Mood; D008297:Male; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales; D011602:Psychophysiologic Disorders / Q000175:diagnosis / Q000453:epidemiology / Q000523:psychology; D013001:Somatoform Disorders