Generalized Anxiety Disorder

The Diagnostic and Statistical Manual of Mental Disorders characterizes generalized anxiety disorder (GAD) as a problem attributable largely to excessive worry. In recognition of the heightened levels of worry and anxiety common to all anxiety disorders, some have considered GAD a core anxiety disorder. Although worry is central to GAD, additional necessary features for the diagnosis include the following:

• Difficulty controlling the worry
• Combinations of three or more physical and emotional concomitants of the worry (i.e., restlessness, easily fatigued, concentration and attention problems, irritability, muscle tension, and sleep disturbance)
• Worry is not due only to another primary psychological problem (i.e., worrying about having a manic episode in the case of bipolar disorder).
• Significant impairment  in  social,  occupational,  or role functioning
• Worry and associated disturbance is not due to effects of a substance or other medical problem

Etiological Factors

Although worry is considered a core feature of anxiety disorders, and GAD is considered a classic anxiety problem, there is little consensus regarding the etiologies of both worry and GAD. In general, individuals with GAD have high trait anxiety, which is the stable tendency to respond to stress with high levels of anxiety. One etiological model proposes that GAD arises from several, largely genetic, predispositions. These genetic predispositions are associated with a general anxious vulnerability, composed of the following elements:

• Processing bias: the tendency to view neutral or ambiguous stimuli as threatening, and a corresponding tendency to conclude there are no alternatives to exposure to threat
• Avoidance: a coping style that is excessively reliant on avoidance of the threatening stimuli as a means of managing anxiety
• Arousal/emotionality: refers to the heightened physical arousal, interpreted by the individual as anxiety that accompanies the processing bias

A closely related etiologic explanation of worry in general, and GAD in particular, involves avoidance theory. Central to this perspective is the counterintuitive premise that worrying shields the individual from experiencing even greater levels of anxiety associated with anticipated poor coping and a resultant negative outcome. At a basic level, chronic worriers have been found to have significantly less physiological arousal when worrying (a predominantly verbal activity) than while imagining a scene associated with the worry. Additional evidence suggesting that worriers have a basic assumption of poor coping ability shows that individuals with chronic worry also perceive themselves as less effective when faced with challenges and responding to stress.

Problematic in conceptualizations of GAD and worry is the role of worry in everyday life. Worry is a common experience, and many have suggested it is essential for some tasks, particularly certain types of problem solving where the individual has lower confidence in their ability to meet the challenge posed. Investigators have speculated that GAD is a fairly common disorder (lifetime prevalence between 4% and 7%), but drawing a clear distinction between normal (and possibly intense) worry compared with pathological worry has been difficult.

Treatment

The availability of empirically supported treatment for GAD is fairly recent. Most of the research investigating how to manage excessive worry has involved a combination of cognitive and behavioral interventions. These interventions have been varied, ranging from individually applied relaxation or biofeedback to comprehensive treatment packages such as multicomponent cognitive behavioral therapy (CBT) or anxiety management training. A recent review of the available treatment literature supports CBT as producing the best outcome (both immediate and with maintenance of gains).

CBT, as it is currently applied for GAD, involves identifying specific errors in thinking that contribute to worry, including faulty beliefs about the likelihood of catastrophe and a pessimistic view of one’s chances of coping successfully. However, unlike in the case of obsessive-compulsive disorder (OCD), individuals with GAD appear to have a wider range of cognitive distortions. Some common distortions are as follows:

• Fortune telling: in the absence of supporting evidence, the specific belief that the future events will turn out negatively
• Negative filtering/positive discounting: an increased focus on negative outcomes, while downplaying positive events as trivial
• Overgeneralizing: applying  the  negative  outcome from one event and assuming it will occur the same way for all other events
• Black and  white  thinking:  placing  all  events  into either all positive or all negative categories, with no intermediary conditions

These common distortions may contribute to worry, although none of these is pathogenic of worry, and can be readily identified in other conditions. So what makes these cognitive distortions particularly relevant in the case of worry? Notice that in most of the cognitive distortions, there is a future-oriented negative outcome. This is one fundamental distinction that can be brought to bear for anxiety conditions in general, and for worry in particular.

Treatment using CBT involves systematically identifying which of these distortions best apply to someone with worry. Once this has been established, the client and therapist engage in a collaborative effort to determine how to challenge these spontaneously occurring distortions and to apply these  challenges  in  situations  that  give  rise  to worry.

As noted, CBT is a comprehensive treatment package. Other important components include training GAD sufferers in more effective problem solving than chronic worrying and exposure to reduce the naturally occurring avoidance that worry produces. Problem solving involves developing a systematic approach to understanding the common problems that individuals face and determining ways of best resolving the situations. These analogue problems can then be applied to problems common to the client. This frequently includes managing emotional responses when faced with difficult situations and understanding that not all problems are readily solved. With repeated practice, adaptive coping responses would be strengthened, particularly for some ongoing problems that require periodic management.

Although CBT has been found to be an effective treatment for GAD, the most recent research suggests that interpersonal functioning must also be addressed in order for GAD sufferers to achieve a long-term positive outcome. Preliminary evidence from one treatment outcome study suggests that individuals with GAD who receive an additional treatment component focused exclusively on interpersonal functioning have improved progress. The mechanism of action for the improved outcome associated with interpersonal functioning among worriers is not clear. However, it has been speculated that improved interpersonal functioning also improves perspective taking (frequently addressed in CBT via challenging cognitive distortions) and increases the GAD sufferer’s sense of effectiveness.

References:

1. American Psychiatric (2000). Diagnostic and statistical manual of mental disorders (4th ed., text revision). Washington, DC: Author.
2. Anxiety Network  International,  http://www.anxietynetwork.com/gahome.html
3. Barlow, H. (2002). Anxiety and its disorders: The nature and treatment of anxiety and panic (2nd ed.). New York: Guilford.
4. Davey, G. C. L. (1994). Pathological worrying as exacerbated problem-solving. In Davey & F. Tallis (Eds.), Worrying: Perspectives on   theory,   assessment,   and   treatment (pp. 35–59). Chichester, UK: Wiley.
5. Heimberg,  G.,  Turk,  C.  L.,  &  Mennin,  D.  S.  (2004). Generalized anxiety disorder: Advances in research and practice. New York: Guilford.
6. National Institute of Mental Health Therapy Advisor, http://www.therapyadvisor.com/taDisorder.aspx?disID=7
7. National Mental  Health  Association,  http://www.nmha.org/infoctr/factsheets/31.cfm
8. Rapee, R. M. (2001). The development of generalized anxiety. In W. Vasey & M. R. Dadds (Eds.), The developmental psychopathology of  anxiety  (pp. 481–503).  New York: Oxford.