Generalized anxiety disorder within the course of major depressive disorder: examining the utility of the DSM-IV hierarchy rule.
BACKGROUND
The current Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR) specifies that generalized anxiety disorder (GAD) should not be diagnosed if it occurs exclusively during an episode of a major depressive disorder (MDD) or another mood disorder. This hierarchy rule was intended to promote diagnostic parsimony, but may result in the loss of important clinical information. The goal of this study was to compare individuals with MDD, comorbid MDD and GAD, and GAD within the course of MDD at intake and 12-month follow-up on self-report measures, clinician ratings, and rates of comorbidity.


METHODS
Participants were divided into three diagnostic groups: MDD without GAD (n=124), comorbid MDD and GAD (n=59), and GAD within the course of MDD (n=166). All the participants completed a semi-structured clinical interview and self-report measures assessing psychopathology, temperament, and functional impairment. A subset of the total sample completed a follow-up assessment of 12 months postintake.


RESULTS
Individuals with comorbid MDD and GAD and GAD within the course of MDD reported more psychopathology, negative affect, and functional impairment at intake than individuals with MDD only. The presence of GAD at intake, however, did not differentially predict symptom severity, functional impairment, or the presence of comorbidity at 12-month follow-up.


CONCLUSIONS
Cross-sectional findings indicate that individuals with GAD within the course of MDD experience levels of psychopathology, functional impairment, and comorbidity similar to those found in individuals with comorbid GAD and MDD. Preliminary longitudinal findings, however, suggest that the presence of GAD in patients with MDD does not have prognostic significance.
Department of Clinical Psychology, Center for Anxiety and Related Disorders, Boston University, 648 Beacon Street, 6th Floor, Boston, MA 02215, USA. alawrenc@bu.edu
Amy E
AE
Lawrence
Gabrielle I
GI
Liverant
Anthony J
AJ
Rosellini
Timothy A
TA
Brown
D000379:Agoraphobia / Q000145:classification / Q000175:diagnosis / Q000453:epidemiology; D001008:Anxiety Disorders / Q000145:classification* / Q000175:diagnosis* / Q000453:epidemiology; D015897:Comorbidity; D003430:Cross-Sectional Studies; D003865:Major Depressive Disorder / Q000145:classification* / Q000175:diagnosis* / Q000453:epidemiology; D039721:Diagnostic and Statistical Manual of Mental Disorders; D004185:Disability Evaluation; D005500:Follow-Up Studies; D006760:Hospitalization; D006801:Humans; D033182:Intention; D008137:Longitudinal Studies; D016584:Panic Disorder / Q000145:classification / Q000175:diagnosis / Q000453:epidemiology; D010555:Personality Inventory / Q000706:statistics & numerical data; D010698:Phobic Disorders / Q000145:classification / Q000175:diagnosis / Q000453:epidemiology; D011594:Psychometrics; D011599:Psychopathology; D013405:Suicide / Q000523:psychology; D013694:Temperament