Psychophysiological Identification of Depression Subtypes in Older Adults: Problematic Diagnostic Heterogeneity in the DSM-III-R and DSM-IV

The DSM-IV does not subclassify patients with depression on the basis of anxiety level. Hence a significant confound may exist in all outcome studies that employ DSM definitions of depression. To establish that objectively identifiable anxious and nonanxious subtypes of depression do indeed exist, a psychophysiological assessment battery was used with 114 treatment-seeking older adults. Dichotomous criterion categorization as either Nonanxious Depressed or Anxious Depressed was based on (a) DSM-III-R/DSM-IV diagnosis, and (b) standardized questionnaires of psychopathology. Multivariate analyses revealed no differences between groups when DSM criteria were used to classify participants. However, identical analyses using phenomenological diagnostic criteria indicated that anxious and nonanxious depressed participants differed in their psychophysiological response to negative imagery. Although anxious and nonanxious depressed participants evince different psychophysiological response patterns, these differences unfortunately are obscured by the DSM. Consequently, a phenomenological classification system may be more appropriate with affective disorders.