396 TREATMENT OF SPECIFIC ANXIETY DISORDERS
Despite some evidence of cross- national differences in GAD prevalence (e.g., Gater
et al., 1998), no ethnic differences emerged in the NCS (Kessler et al., 1994). However,
in the NCS-R non- Hispanic black and Hispanic participants had significantly lower
rates of all anxiety disorders than non- Hispanic whites (Kessler, Berglund, et al., 2005).
Cultural differences may be seen in worry content, with Asian Americans significantly
more worried about future goals and African Americans worried significantly less than
Asian Americans or Caucasian Americans about relationships, self- confidence, future
aims, or work incompetence (Scott, Eng, & Heimberg, 2002).
Onset and Age Differences
In the NCS-R 50% of GAD cases had an onset under 31 years of age and 75% had an
onset before 47 years old (Kessler, Berglund, et al., 2005). Compared with the other
anxiety disorders assessed in the NCS-R, a higher percentage of GAD cases had a late
onset, with approximately 10% having a first occurrence after 60 years of age. How-
ever, in their review Holaway, Rodebaugh, and Heimberg (2006) concluded that late
teens to late 20s was the most common age range for the onset of GAD.
Given the broader age range for GAD onset, there has been considerable interest
in rates of GAD across the lifespan, especially among older adults. In the NCS-R life-
time prevalence was highest in the 45–59 age cohort (Kessler, Berglund, et al., 2005),
whereas Holaway, Rodebaugh, and Heimberg (2006) concluded that 25–54 years had
the highest prevalence of GAD. For individuals younger than 18 years old, overanxious
disorder is diagnosed as the counterpart to GAD. Overanxious disorder in childhood
and adolescence is associated with increased risk for GAD and major depression in
adulthood (e.g., Mofitt et al., 2007).
A Dutch community survey of 4,051 individuals between 65 and 86 years of age
found that 3.2% met criteria for current GAD and 60% of these cases had concurrent
depression (Schoevers, Beekman, Deeg, Jonker, & van Tilburg, 2003). Although GAD
appears to have the same clinical presentation in older and younger individuals (J. G.
Beck, Stanley, & Zebb, 1996), Mohlman (2004) indicated that the disorder may be
harder to detect in older adults. She concluded that older adults may worry less than
younger age groups, and the content and their response to worry may differ. Older
adults worry more about health, death, injury, and work affairs, whereas younger indi-
viduals worry about work and relationships, and they rely on different strategies to con-
trol their worry (Hunt, Wisocki, & Yanko, 2003). Moreover, CBT may produce more
modest treatment effects with older GAD patients (see Mohlman, 2004). Evidence that
older adults with major depression and GAD may have more suicidal ideation highlights
the clinical importance of GAD symptoms in this segment of the population (Lenze et
al., 2000). However, more recent research indicates that GAD is not associated with a
higher mortality rate in the elderly (Holwerda et al., 2007).
Clinician Guideline 10.5GAD is the third most common anxiety disorder with a lifetime prevalence of 5.7%. It is twice
as common in women and may be somewhat more prevalent among Caucasians. Higher