Comorbidity as a fundamental feature of generalized anxiety disorders: results from the National Comorbidity Study (NCS).
Generalized anxiety disorder (GAD) is a relatively common mental disorder in the general population, afflicting approximately 3% of community residents during their lifetime. It is not a benign condition, since significantly increased disability and dysfunction are found in GAD subjects compared to non-GAD subjects. For decades GAD has frequently been observed in the context of other mental and substance abuse disorders. Initially the weight of clinical opinion indicated that GAD was a residual disease which should only be diagnosed when other mental disorders are not present. More recently there has been a growing recognition that comorbidity is a fundamental characteristic of the course and nature of GAD. In a series of secondary analyses conducted in subjects in the National Comorbidity Study database, we found that 8 out of 10 subjects with lifetime GAD also had a comorbid mood disorder during their lifetime. We found unipolar disorders to be four times more common in GAD than bipolar disorders (67% vs. 17%), providing indirect support for the previously reported observation that GAD and major depression may share a common genetic diathesis. In addition, our analyses support the conclusion that when comorbid mood disorders are present in GAD, a significant increase in associated disability and dysfunction is also found. Thus this comorbid relationship has important implications for clinical course and outcome.
Department of Psychiatry, University of California San Diego, USA.
L L
LL
Judd
R C
RC
Kessler
M P
MP
Paulus
P V
PV
Zeller
H U
HU
Wittchen
J L
JL
Kunovac
D000293:Adolescent; D000328:Adult; D001008:Anxiety Disorders / Q000175:diagnosis / Q000453:epidemiology* / Q000523:psychology; D015897:Comorbidity; D003865:Major Depressive Disorder / Q000175:diagnosis / Q000453:epidemiology* / Q000523:psychology; D005260:Female; D006306:Health Surveys; D006801:Humans; D008297:Male; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales; D014481:United States / Q000453:epidemiology