Comorbidity as a fundamental feature of generalized anxiety disorders: results from the National Comorbidity Study (NCS)

Acta Psychiatr Scand Suppl. 1998;393:6-11. doi: 10.1111/j.1600-0447.1998.tb05960.x.


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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Anxiety Disorders / diagnosis
  • Anxiety Disorders / epidemiology*
  • Anxiety Disorders / psychology
  • Comorbidity
  • Depressive Disorder, Major / diagnosis
  • Depressive Disorder, Major / epidemiology*
  • Depressive Disorder, Major / psychology
  • Female
  • Health Surveys
  • Humans
  • Male
  • Middle Aged
  • Psychiatric Status Rating Scales
  • United States / epidemiology