224 Eating Disorders
Toner, Garfinkel, and Garner (1988) reported a rate of 40 percent; and
Halmi et al. (1991) reported a rate of 68 percent. It was also consistently
found in all these studies that the presence of depression was unrelated to
the outcome of the anorexia, and there was a trend for depression to be
higher among those anorexics who binged or purged (Halmi, 1995).
Lunde et al. (2009) explored the prevalence of bipolar disorder in patients
with either AN or BN and reported that bipolar disorder was higher in
patients with an eating disorder than those without an eating disorder but
was only significantly higher in those with BN rather than AN.
Anxiety disorders also co-occur alongside anorexia. For example,
Halmi et al. (1991) reported a rate of 65 percent and Toner, Garfinkel, and
Garner (1988) reported a rate of 60 percent in their patient populations.
From these data the most common anxiety disorders are social phobia and
obsessive compulsive behaviors (Wu, 2008).
Causes or consequences?Most physical complications associated with anorexia can be analyzed as
the consequences of the disorder. Starvation clearly causes skeletal and teeth
problems and may ultimately cause death. The connection between anorexia
and psychological problems is more complicated. Anorexics show both
depression and anxiety, and this association has generated debates as to
whether such psychological morbidity is a cause or a consequence of an
eating disorder. Alternatively, depression and anxiety may be neither causes
nor consequences but just manifestations of the problem itself. In fact, Crisp
in 1967 conceptualized anorexia as a phobic disorder, and Brady and
Rieger (1972) described an anxiety-reduction hypothesis which suggested
that eating created anxiety in anorexics which was removed by food avoid-
ance. Thus food avoidance and/or purging is reinforced through anxiety
reduction. However, given that the rates of depression appear to remain
constant throughout the treatment of anorexia, that depression is unre-
lated to recovery (Halmi, 1995), and that social phobia often precedes the
onset of anorexia (Brewerton, Hand, and Bishop, 1993), these affective
disorders are better considered secondary psychopathology rather than
primary (Strober and Katz, 1987). They are therefore comorbidities which
may predispose an individual towards developing an eating disorder and
may even perpetuate the problem, but do not cause it. Neither would their
treatment result in a decline in the anorexia.