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disorders, and less than half succeed in making a stable long-term intimate
relationship. Around 2% die from starvation or suicide. Some individuals
start out with the restrictive type of anorexia, change to having the
binge-eating/purging type of anorexia, and then make the transition to
bulimia nervosa. Factors predicting a poor outcome include greater weight
loss, vomiting, binge eating, greater chronicity, prepubertal onset and
premorbid abnormalities. Possible indicators of a better outcome include
early (but post-pubertal) onset, good parent–child relationships, and rapid
detection and treatment.
Bulimia nervosa
Diagnosis
Bulimia nervosa involves frequent episodes of out-of-control overeating in
which large amounts of food are consumed in short periods; the disorder
should not be diagnosed on the basis of binges that occur exclusively
during periods when the individual also meets the criteria for anorexia
nervosa. Binges take place against a background of a persistent craving
for, or preoccupation with, food. The individual counteracts the fattening
effects of binges by means of deliberate vomiting, purging, periods of
starvation, or other means. Body weight is usually close to normal, but
concern about body weight is heightened.
Epidemiology
The peak age for bulimia is slightly later than for anorexia, but there
is a similarly marked excess of females. Though epidemiological studies
suggest that bulimia may be more common than anorexia in the general
population, bulimia is underrepresented in clinic samples.
Causation
Bulimia may reflect exposure to a combination of risk factors for psy-
chopathology in general (for example, parental neglect, sexual abuse) and
risk factors for dieting in particular (for example, premorbid overweight).
Treatment
Most affected individuals can be treated as out-patients with cognitive-
behavioural therapy, which is generally the treatment of choice, though
there is some evidence for the effectiveness of selective serotonin reuptake
inhibitors (SSRIs) such as fluoxetine. In the long term, roughly 50%
recover fully, 25% improve, and 25% have a chronic course, often char-
acterised by remissions and relapses. Co-existent or subsequent depression
is common and may need treating in its own right.