PsychologyOrbit
Sign in Join

What is Generalised Anxiety Disorder?

Excessive, difficult-to-control worry about multiple areas of life, present more days than not for at least six months, with physical symptoms such as restlessness, muscle tension, fatigue and disturbed sleep.

From the PsychologyOrbit knowledge base, last updated 2 November 2026.

Knowledge base Updated 2 November 2026 1 views

Generalised Anxiety Disorder

Excessive, difficult-to-control worry about multiple areas of life, present more days than not for at least six months, with physical symptoms such as restlessness, muscle tension, fatigue and disturbed sleep.

Definition

GAD is defined by worry that is excessive relative to circumstance, difficult to control, spread across several domains rather than focused on one, and accompanied by at least three physical symptoms.

The six-month duration requirement distinguishes it from transient anxiety and is the criterion most often criticised as arbitrary.

Theory

Several complementary accounts, and unusually for this field they agree more than they compete.

  • Intolerance of uncertainty: the driving vulnerability is not the content of worries but an inability to tolerate not knowing. This has the strongest evidence of the specific accounts.
  • Avoidance model (Borkovec): worry is verbal-linguistic and suppresses the vivid imagery and autonomic arousal that emotional processing requires, so it is negatively reinforced while preventing resolution.
  • Metacognitive model (Wells): the problem is beliefs about worry — both that it is useful and that it is uncontrollable — rather than the worry itself.

The practical convergence is that treatment targets the relationship to uncertainty and to worry, not the plausibility of each individual worry.

Research

Lifetime prevalence around 5 to 6 percent, roughly twice as common in women, and typically chronic with a fluctuating course rather than episodic.

CBT has good evidence, with effect sizes somewhat smaller than for panic or specific phobia. Metacognitive therapy and intolerance-of-uncertainty protocols have promising but smaller literatures.

Comorbidity is very high, particularly with depression, and GAD is one of the conditions where whether it is a distinct disorder is genuinely open.

Applications

The GAD-7 is the standard brief measure and is widely used in primary care.

Treatment is usually CBT, with SSRIs or SNRIs as an alternative. Benzodiazepines are not recommended for ongoing treatment: they work quickly, and dependence plus rebound anxiety makes them a poor long-term option.

Criticism

  • Distinctness from depression is unresolved. They share genetic variance, they co-occur at high rates, and some researchers argue for a single internalising dimension rather than two disorders.
  • The six-month rule excludes people with severe, impairing worry of shorter duration for no principled reason.
  • The diagnosis changed substantially across DSM editions, which makes the older prevalence and treatment literature hard to compare with the newer.
  • Worry is normal. Where excessive begins is a judgement, and it is a judgement made in a cultural context.

References

  • Borkovec, T. D., Alcaine, O., & Behar, E. (2004). Avoidance theory of worry and generalized anxiety disorder. In R. G. Heimberg, C. L. Turk, & D. S. Mennin (Eds.), Generalized Anxiety Disorder: Advances in Research and Practice (pp. 77-108). Guilford Press.
  • Dugas, M. J., et al. (1998). Generalized anxiety disorder: A preliminary test of a conceptual model. Behaviour Research and Therapy, 36(2), 215-226.
  • Wells, A. (2005). The metacognitive model of GAD. Cognitive Therapy and Research, 29(1), 107-121.
  • Spitzer, R. L., et al. (2006). A brief measure for assessing generalized anxiety disorder: The GAD-7. Archives of Internal Medicine, 166(10), 1092-1097.
Written for PsychologyOrbit and reviewed before publishing. It is a summary for professionals and students, not clinical guidance, and it is not a substitute for the primary sources listed above.