Symptom and factor structure profiles of dysthymia and major depression

Abstract

The placement of Dysthymic Disorder in the Affective Disorders section of DSM-III represented a dramatic turnabout in the concept of chronic depression which, in DSM-II, had been classified under the personality disorders and neuroses. This study compared the symptom profiles and factor structures of two groups: 124 psychiatric outpatients diagnosed with Dysthymic Disorder, and 106 psychiatric outpatients diagnosed with acute Major Depressive Disorder. Two-thirds of each sample was female. Major depressives were somewhat older (x = 43.91) than the dysthymics (x = 38.17).;The study contained five hypotheses. The first predicted that major depressives would have higher depression severity scores on the clinician-rated Hamilton Rating Scale for Depression (HAM-D). No between-group difference was expected on the self-rated Beck Depression Inventory (BDI). This hypothesis was supported.;The second hypothesis predicted different between-group qualitative HAM-D symptom profiles. This hypothesis was also supported. Major depressives displayed more severe neurovegetative symptoms than dysthymics; there was no such difference when most cognitive and affective symptoms were compared.;The third and fourth hypotheses predicted different between-group factor structures. These hypotheses were supported. Difficulties in reality testing differentiated the two groups: major depressives suffered from more general reality testing problems, while dysthymics suffered from focal reality testing difficulties related to hypochondriasis and passively self-destructive tendencies.;The fifth hypothesis predicted primary factors of cognitive/affective symptoms among dysthymics, and somatic/neurovegetative symptoms among major depressives. This hypothesis was partially supported, but the results were more ambiguous. Analyses yielded factors which were predominantly cognitive/affective or somatic/neurovegetative, yet these factors were not composed of identical items, nor were they always the first or second factors identified.;These results make further research into the classification of, and nosological distinction between, depressive subtypes more pressing. Further, differences appear to exist between the clinician's perception and the patient's perception of depressive states; these differences are even more striking when the sexes are compared. Finally, an argument is put forth suggesting that Major Depressive Disorder is correctly classified as an acute Axis I disorder, but that Dysthymic Disorder is more accurately characterized as an Axis II personality disorder.