In this issue of the Archives, Kessler et al1 provide a thorough account of the meaning of comorbidity among DSM-IV mental disorders. Their contribution involved comparing hypotheses regarding the developmental sequencing of comorbidity. One hypothesis was that specific disorders are involved in specific developmental comorbidity patterns. For example, obsessive-compulsive disorder might generally be a primary disorder, with that disorder then leading people to have few social contacts owing to the debilitating nature of their symptoms. Diminished social involvement might typically contribute to the development of a secondary major depressive episode in persons who have a primary diagnosis of obsessive-compulsive disorder. Numerous plausible pathways of this sort can be hypothesized.
Krueger RF, Markon KE. A Dimensional-Spectrum Model of PsychopathologyProgress and Opportunities. Arch Gen Psychiatry. 2011;68(1):10-11. doi:10.1001/archgenpsychiatry.2010.188