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Anorexia nervosa (AN) remains, for most patients who fall ill,
a treatment-resistant, chronic illness with significant morbidity
and mortality. Over the past 50 years, little progress has been
made in developing new, effective treatments for the disorder. The
last 2 decades have seen the development of a better understanding
of the importance of the starvation state in perpetuating the disorder
(1) and the absolute necessity for nutritional rehabilitation through
a multidisciplinary approach to treatment. As a result, the mortality
rate of AN has decreased somewhat over this time. However, the appropriate
treatment for AN is still the subject of much debate, and research
into effective management that truly impacts on long-term outcome
is lacking. This striking lack of effective psychological and pharmacologic
interventions for AN contrasts sharply with newly developed effective
treatments for bulimia nervosa (BN). Since the first description
of BN as a distinct entity in 1979 (2), numerous randomized controlled
trials have demonstrated the efficacy of psychological and pharmacologic
treatments for BN. This paper focuses exclusively on psychological
treatments for AN; another paper in this issue of the Journal (227–34)
reviews pharmacological approaches to AN and BN. First, this review
examines the relatively few published randomized controlled trials
using psychological treatments for AN in both adolescents and adults.
Then, it describes promising new psychosocial approaches for AN,
focusing primarily on motivational enhancement therapies (MET).
Based more on clinical consensus and prevailing practice than on
empirical evidence, psychotherapy remains the cornerstone of treatment
for AN. The evidence for the efficacy of psychological treatments
comes primarily from case reports and the few studies that have
been conducted, and this evidence is far from definitive. Surprising
is the fact that few randomized controlled trials evaluating the
effectiveness of psychological treatments for acute AN have been
conducted in the over 125 years since the first recorded clinical
description of the disorder (3,4). These published studies are reviewed
here.
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Randomized Controlled Studies of Active Anorexia
Nervosa
Individual Psychotherapies
In examining outpatient treatment trials, studies that have attempted
to compare active psychotherapy, usually cognitive-behaviour therapy
(CBT), with some other form of psychosocial intervention—either
psychoeducation or nutritional counselling in adult subjects with
active AN—have had difficulty demonstrating specificity of
effectiveness for the active psychotherapy used. This, in part,
relates to the small number of subjects entered into these studies,
which limits the power to distinguish between different treatments.
For example, Channon and others randomized adult outpatients with
AN to 3 treatments: CBT, behaviour therapy, and control treatment
that consisted of nonspecific support and medical monitoring (5).
However, there were only 8 subjects randomized to each of the treatment
cells, making the interpretation of outcome differences between
the different treatments somewhat problematic. In fact, no significant
differences were found on any of the significant outcome measures
between the 3 groups. In another study—the only published randomized
controlled trial of psychodynamic psychotherapy comparing a brief
structured psychodynamic psychotherapy (cognitive analytic therapy)
with an educational behaviour therapy—16 adult outpatients
with active AN were randomized to the former treatment and 14 to
the latter. This study did not find any differences in end-of-treatment
outcome in this small number of randomized subjects (6). Of the
total group, 63% (19 out of 30) had a good or intermediate nutritional
outcome after 5 months of active treatment. At 1-year follow-up,
37% of the total number of patients had recovered, with no difference
in outcome between treatment groups.
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