The validity of diagnosis of melancholic depression according to differentdiagnostic systems

Background: Melancholic versus nonmelancholic depression dichotomy is perha ps the most widely accepted distinction in categorization of depression. Th is research aims to compare RDC, DSM-III, DSM-III-R, DSM-IV and ICD-10 mela ncholic/endogenous/somatic and nomelancholic/nonendogenous/nonsomatic depre ssive patients with regards to biological variables thyroid stimulating hor mone (TSH), basal and post dexamethasone cortisol levels, age, age of onset of depression, psychosocial stressors, and severity of depression. Methods : Sixty-five patients who had been diagnosed as having major depression acc ording to DSM III-R, using SCID were included in this study. Patients were divided into melancholic and nonmelancholic subtypes using RDC, DSM-III, DS M III-R, DSM-IV and ICD-10 criteria and groups were compared on the basis o f biological variables, as well as age, psychosocial stressors and the seve rity of depression. Results: RDC endogenous depressives were older, more se verely depressed and had higher cortisol levels then RDC nonendogenous depr essives. DSM III-R melancholics were older, more severely depressed, report ed fewer numbers of psychosocial stressors and had lower levels of TSH than nonmelancholics. DSM-IV melancholics were more severely depressed, had hig her basal and post dexamethasone cortisol levels and lower TSH levels. The ICD 10 somatic depression group contained more severe, older depressives wi th lower TSH levels. Conclusion: The results of this research show that dif ferent criteria may identify different groups of patients as having melanch olic depression. They also partly support the hypothesis that endogenous or melancholic depression have a biological basis. Limitations of study: The study involved a relatively small sample size from a single centre and the results are based on this relatively small sample. (C) 1999 Elsevier Scienc e BN. All rights reserved.