AN is characterised by an intense fear of weight gain. It involves an
ongoing pattern of self starvation and a preoccupation with control over
food and weight
DSM-V further specifies that an individual may
also present with persistent behaviour that infers
with weight gain despite being at a low weight.
Additionally, the DSM-V also specifies disturbances in the way body weight or shape is
perceived, disproportionate influence of body weight on self evaluation, and lack of
recognition of seriousness of current low body weight.
Typically you'd expect to see weight below 85% of expected weight. However,DSM-V
removed a definitive weight requirement for diagnosis and instead requires for
weight to be considered in the context of age, sex, dev trajectory and physical health.
Key physical
symptoms
Amenorrhea (loss of
period)
Low body weight
loss of hair
Low pulse rate and sensitivity to
cold
Key psychological/behavioural
symptoms
Perfectionism and high self
criticism
Social
Isolation
Playing with or cutting food into small
pieces
May have alternating episodes of
purging and binge eating
Compulsive exercise and/or
cleaning
Nervousness at meal times
Bulimia Nervosa
Main Characteristics
In constrast to AN, BN is characterised by recurrent episodes of binge eating followed by
compensatory strategies including self induced vomiting, use of laxatives or diuretics, restriction
or excessive exercise.
Whilst a pattern of purging and
binging can be seen in AN, it is not
the core feature of diagnosis whereas
a recurrent pattern of binging
followed by inappropriate
compensatory strategies is core to BN
diagnosis. Further, the DSM requires
that this pattern does occur
exclusively during episodes of AN.
Additionally, weight is typically average or above
average
Key Physical
Symptoms
Frequent Vomiting
Tooth decay and oesophagus damage due to
this
Weight fluctuation due to bingeing and
fasting
Puffiness in Face
Key Behavioural/Psychological
Symptoms
Fear or inability to stop
eating
Secretive behaviour and inconspicuous binge
eating
Perfectionism
Petty stealing of money to buy food for
binges.
Binge Eating
Disorder
Main Characteristics
BED is characterised by recurrent episodes of binge eating but, in contrast to BN, in the absence
of inappropriate compensatory behaviours. Weight may be normal but is more likely to be
overweight.
Key physical
symptoms
Possible history of marked weight
fluctuations
Key Psychological or Behavioural
Symptoms
Eating alone due to embarrassment over how much one is
eating
Sense of lack of control over
binging
Feeling guilty or depressed after
binging
Other Specified Feeding or Eating Disorder
(OSFED)
Why does this category exist?
In DSM-IV about 50% of patients fell into other specified eating
disorder therefore this category was developed to provide more
specific diagnosis to account for this
Included diagnoses under this
category
Atypical AN: despite sig weight loss, weight is at or above normal
range.
Purging disorder: recurring
purging to influence shape or
weight in the absence of
binging.
Sub threshold BN or BED: Behaviours occur less than one week or less than three
months.
Night eating syndrome
Recurrent episodes of night eating, associated with significant
distress
Avoidant/Restrictive Food Intake Disorder
(ARFID)
Main characteristics of
ARFID
ARFID is characterised by eating or feeding disturbance and
persistent failure to meet energy needs which is not
accounted for by lack of available food or cultural practices.
Three subtypes; those who do not eat enough and/or show little
interest in eating, those who accept limited diet in relation to
sensory features, and where food refusal is related to aversive
experiences.
Distinguished from AN or BN as there is no disturbance in how one views or
experiences body weight or shape. The focus of diagnosis is purely on restrictive or
avoidant behaviour in relation to eating.
Issues
Difficulties with Diagnosis
There is a lot of overlap in symptoms so this can make diagnosis challenging
Interpretation needed but this can be limited by developmental context and
co-morbity.
Transdiagnosis
Migration across
disorders
Patients with eating disorders tend to migrate between the
diagnostic categories of anorexia nervosa, bulimia nervosa,
and the atypical eating disorders (Fairborn and Harrison,
2003)
This temporal movement, together with the fact that anorexia
nervosa, bulimia nervosa, and the atypical eating disorders
share the same distinctive psychopathology, suggest that
common mechanisms are involved in their persistence.
Given this, it is arguably more helpful to take a transdiagnostic approach to eating
disorders.
However, where do we draw the line? High co-morbidity means you could argue that there is significant
overlap between EDs and other disorders and therefore, EDs could be considered part of these disorders.
Yet, the fact that eating disorders do not tend evolve into other conditions lends
support to the distinctiveness of the diagnostic category as a whole.