title: Treatment resistance in severe unipolar depression: no association with psychotic or melancholic features.
abstract: BACKGROUND
  Depressive subtypes generally have been neglected in research on treatment efficacy. We studied a sample of 699 severe unipolar depressed patients to detect any association between depressive features and treatment resistance.
  
  
  METHODS
  Participants were divided into psychotic (PSY, n = 90), melancholic (MEL, n = 430) and non-melancholic (n = 179) subjects according to clinical features. Formal diagnostic criteria (Mini International Neuropsychiatric Interview items), and items from 17-item Hamilton Rating Scale for Depression (HRSD17) were compared across groups. Non-responders were defined by a HRSD17 cut-off score of ≥17 after the last adequate antidepressant treatment. Treatment-resistant depression (TRD) was defined as the failure to respond to ≥2 adequate antidepressant trials. Non-linear regression models were designed to detect associations between depressive subtypes and TRD.
  
  
  RESULTS
  PSY and MEL patients appeared to be more severely affected and to share some "core" melancholic symptoms. Both PSY and MEL patients reported a higher rate of seasonality. However, we found no clinical or illness course variable associated with TRD.
  
  
  CONCLUSIONS
  Our results indicate that psychotic and melancholic depression share some "core" melancholia symptoms, while no distinguishing psychopathological feature appears to be associated with TRD in severely depressed patients.
authors: Institute of Psychiatry, University of Bologna, Bologna, Italy.
authors: Leonardo
authors: L
authors: Zaninotto
authors: Daniel
authors: D
authors: Souery
authors: Raffaella
authors: R
authors: Calati
authors: Othman
authors: O
authors: Sentissi
authors: Siegfried
authors: S
authors: Kasper
authors: Elena
authors: E
authors: Akimova
authors: Joseph
authors: J
authors: Zohar
authors: Stuart
authors: S
authors: Montgomery
authors: Julien
authors: J
authors: Mendlewicz
authors: Alessandro
authors: A
authors: Serretti
mesh_terms: D000328:Adult; D000341:Affective Disorders, Psychotic / Q000188:drug therapy / Q000523:psychology*; D000928:Antidepressive Agents / Q000627:therapeutic use; D003866:Depressive Disorder / Q000188:drug therapy / Q000523:psychology*; D061218:Depressive Disorder, Treatment-Resistant / Q000145:classification / Q000188:drug therapy / Q000523:psychology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012720:Severity of Illness Index
chemical_list: D000928:Antidepressive Agents