392 TREATMENT OF SPECIFIC ANXIETY DISORDERS
to depression than any of the other anxiety disorders. This juxtaposition of GAD with
depression has implications for treatment. For example, cognitive therapy for general-
ized anxiety draws more directly from standard cognitive therapy for depression than
the treatment protocols for the other anxiety disorders. In addition individuals with
comorbid GAD and major depression have more severe cognitive biases than individuals
who have GAD without comorbid major depression (Dupuy & Ladouceur, 2008).
Clinician Guideline 10.2
GAD is a distress disorder with a similar but distinct diagnostic and symptom structure to
major depression. Clinical assessment and treatment of GAD must include the high prob-
ability of affective disturbance in the form of a co- occurring depressive disorder or symp-
toms.Boundary Issues in GAD
GAD can be difficult to detect because worry is such a common complaint in the general
population as well as in all the anxiety disorders and depression. To improve the differ-
entiation of GAD, DSM-IV-TR requires that the worry be chronic, excessive, pervasive,
associated with some anxious symptoms, and cause clinically significant distress or
impairment. However, is this sufficient? Ruscio (2002) compared non-GAD high wor-
riers and GAD high worriers on various symptom questionnaires. He found that GAD
worriers had significantly higher worry frequency or distress and impairment than the
non-GAD worriers. However, the difference between the two groups was a matter of
degree, with the GAD worriers showing greater severity on most symptom measures
(see also Ruscio, Chiu, et al., 2007). Thus GAD clearly fits a dimensional model of
psychopathology, making it difficult to determine the optimal diagnostic criteria for
differentiating pathological from normal general anxiety.
So, are there symptom features that are distinct to GAD? Barlow and colleagues
have argued that GAD may be distinct by the greater frequency and severity of worries
about a number of life circumstances, especially minor or miscellaneous tasks, as well as
associated muscle tension (Roemer et al., 2002). A variety of constructs have been pro-
posed as unique to GAD such as (1) an unsuccessful search for safety (Rachman, 2004),
(2) activation of negative (metacognitive) beliefs about worry and counterproductive
attempts at thought suppression (Wells, 2006), (3) intolerance of uncertainty (Dugus,
Gagnon, et al., 1998), or (4) deficits in the regulation of emotional experience (Mennin,
Turk, Heimberg, & Carmin, 2004). Unfortunately, empirical evidence that these pro-
posed constructs are indeed specific markers of GAD is lacking at this time.
Clinician Guideline 10.3
There are no qualitative symptom features that are specific to GAD. Rather, the disorder
varies in terms of the chronicity, severity, and pervasiveness of worry and associated anxiety.
For this reason distinguishing GAD from non-GAD high worriers will present special chal-
lenges for the clinician.