Transcript Eating Disorders

Eating Disorders
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Anorexia Nervosa (AN)
 Self-inflicted starvation.
 Peaks occur between 14 and 18 years.
 Average age of onset is 17.
 Most cases develop before age 25.
 10% of hospitalized patients die due to
complications.
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Anorexia Nervosa
 Sharp reduction of food intake.
 Obsessed by the need to be thin, to avoid being
“fat”
 Recommended amount of calories for adolescent
girls is 1500-1800 calories/day.
 Average daily food intake of women with AN is
400-800 calories.
 Very few anorexics are overweight (5%).
 Common in women who are already considered
slim by peers.
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Prevalence
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90-95% of patients are female.
Adolescent females prevalence from 5-20%.
Youngest known patient: 6 years old.
Tends to occur in homosexual more than
heterosexual males.
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Effects on Prevalence
National rates are affected by social factors:
1. Value the broadcast media places on thinness.
2. Value society places on thinness.
3. More prevalent in industrialized countries.
4. More common in families with a high
socioeconomic status.
· Very much a first world mental disorder.
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Case study
 A 14-year old female athlete began high school at the
normal weight of 101 lbs. and a height of 65 inches.
 She participated in track and basketball. Soon after
beginning her freshman year she began to exercise
compulsively. She also restricted her food intake.
 Over the course of the year her weight dropped to 93
lbs. Her parents sought to intervene in her destructive
behavior. She participated in individual as well as family
counseling.
 Despite seeing a dietician her weight continued to drop
and she soon weighed about 84 lbs.
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Case study
 She had been hospitalized and several times doctors
had tried nasogastric tube feedings to increase her
weight. These were unsuccessful because the patient
would remove the feeding tube. Her weight had fallen to
less then 75% of her ideal body weight.
 By the time she was 15, the patient was referred to a
psychiatrist who realized that the patient was exhibiting
signs of obsessive compulsive disorder. Further
counseling uncovered a history of OCD symptoms as far
back as the age of eight.
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AN Profile
• Parents describe them as problem-free
children.
• Often popular, excellent students.
• Perfectionistic, intellectually bright.
• Hold a negative perception of themselves.
• Inflexible, overly sensitive, emotionally
restrained, and introverted.
• Commonly have obsessive-compulsive
behaviours such as ritualized cleaning or
cooking.
• Distorted body image.
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DSM-IV Criteria
A. Refusal to maintain body weight at or above a
minimally normal weight for age and height
e.g., weight loss leading to maintenance of body
weight less than 85% of that expected; or failure
to make expected weight gain during period of
growth, leading to body weight less than 85% of
that expected.
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DSM-IV Criteria
B. Intense fear of gaining weight or becoming
fat, even though they are underweight.
C. Disturbance in the way in which one's body
weight or shape is experienced, undue influence
of body weight or shape on self-evaluation, or
denial of the seriousness of the current low body
weight.
D. In postmenarcheal females, amenorrhea
 the absence of at least three consecutive
menstrual cycles.
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DSM-IV Criteria
1. Restricting Type: the person has not regularly
engaged in binge-eating or purging behavior
2. Binge-Eating/Purging Type: the person has
regularly engaged in binge-eating or purging
behavior
 (i.e., self-induced vomiting or the misuse of
laxatives, diuretics, or enemas)
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Etiology
1. A specific environmental trigger, usually with a
sudden onset, setting off pattern of reduced
eating and obsessively exercising.
2. Many maladadptive personality traits (obsessivecompulsive, social phobia) predate the onset of
AN
 remain following weight normalization.
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Pathology of Undernourishment
1. Wasting of muscle tissue occurs
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May be uncomfortable for them to sit.
Immune system deficits
Poor temperature regulation
Electrolyte imbalance
Wearing down of tooth enamel
Menstruation ceases
Even after recovery, lifelong health
problems occur in 80% of patients
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Bulimia Nervosa (BN)
1. Binging: ingestion of abnormally high quantities
of food
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1500 – 55000 calories.
May be a daily occurrence
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Are aware that binging is abnormal but cannot
control behaviour.
2. Purging: vomiting, laxatives, or excessive
exercise.
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May replace purging with fasting.
Usually close to appropriate weights.
Extreme guilt and concern with becoming fat.
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Prevalence
 Difficult to determine since Bulimics hide their
behaviour, and since eating in public is
appropriate.
 1-3% of adolescent females are affected.
 Up to 20% in college age females.
 Peaks in early adulthood.
 Again, less common in males.
 Often associated with eating problems in
childhood, as well as depression, early childhood
trauma, addictions.
 May be common in certain professions (dancers,
athletes, models)
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Case Study
 “Carla’s” bulimic behavior began at age 11 years after
many unsuccessful attempts to lose weight via caloric
restriction and exercise. Carla is of average height and
above average weight for age.
 Her personal sense of body dissatisfaction was
intensified several years ago by external pressure from
her school coach, peers, and family to lose weight. Carla
was frustrated by her dieting attempts since her caloric
restriction resulted in food cravings and binges due to
intense hunger.
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Case Study
 Her girlfriends at school told her that she could
be successful at weight loss and not have to
restrict food intake by using laxatives and
vomiting after food consumption. Carla and her
friends began to plan purging activities and food
binges together to prevent weight gain and
satisfy their hunger.
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Case Study
 In addition to this behavior, Carla continued to
exercise regularly. Her bulimic behavior caused
her to lose 14 pounds in four weeks. Unaware of
her food addiction, her family and coach
expressed great pride in her weight loss. The
attention and encouragement further reinforced
her behavior and intensified her desire for
thinness.
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Case Study
 Carla’s bulimia progressed rapidly. Within a year
of onset she was bingeing and purging as much
as five times a day with an average of 3,000
calories at each binge. Eventually, it became
increasingly difficult for Carla to focus on her
school work and she withdrew from many social
activities.
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Case Study
 Her boyfriend recognized these changes in her
personality and insisted she talk to the school
nurse for an evaluation. Carla refused to see the
school nurse and tried to assure him that her
bulimic behavior was under control.
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Case Study
 At the same time, some of Carla’s girlfriends
became increasingly concerned about her
condition. They expressed their concern about
Carla with the school nurse and pleaded with
Carla to talk with the nurse. Carla reluctantly
conceded.
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DSM-IV Criteria
A. Recurrent episodes of binge eating.
(1) eating, in a discrete period of time (e.g., within any 2hour period), an amount of food that is definitely larger
than most people would eat during a similar period of
time and under similar circumstances.
(2) a sense of lack of control over eating during the
episode (e.g., a feeling that one cannot stop eating or
control what or how much one is eating).
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DSM-IV Criteria
B. Recurrent inappropriate compensatory behavior in order
to prevent weight gain, such as self-induced vomiting;
misuse of laxatives, diuretics, enemas, or other
medications; fasting; or excessive exercise.
C. The binge eating and inappropriate compensatory
behaviors both occur, on average, at least twice a week
for 3 months.
D. Self-evaluation is unduly influenced by body shape and
weight.
E. The disturbance does not occur exclusively during
episodes of Anorexia Nervosa.
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DSM-IV Criteria
 Purging Type: the person has regularly
engaged in self-induced vomiting or the misuse
of laxatives, diuretics, or enemas
 Nonpurging Type: the person has used other
inappropriate compensatory behaviors, such as
fasting or excessive exercise, but has not
regularly engaged in self-induced vomiting or the
misuse of laxatives, diuretics, or enemas
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Neuropathology in AN
1. In AN, imaging studies show frontal and limbic dysfunction
(Herholz, 1996; Takano et al., 2001):
• hypoperfusion (underactive) in the caudate and anterior
cingulate
• hyperperfusion (overactive) in medial temporal and thalamic
regions
2. “Pseudoatrophy” of the brain
• Malnutrition does affect overall brain size
• Reduction the size of neurons (gray matter)
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Neuropathology
Serotonin Abnormalities
 Especially in cingulate, mesial temporal areas
1. Satiety (how soon one feels full)
2. Food-related reward (hedonic pathways)
3. Mood, anxiety, depression, and personality
characteristics.
 Starvation may serve to alleviate anxiety.
4. Hyperactive motor behaviour.
5. Interaction with estrogens (and with age) in the
brain.
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Regulation of excitatory serotonin receptors.
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Neuropathology
The Sertonergic Hypothesis
In Anorexia Nervosa there is an initial
increase of 5-HT:
 exaggerated satiety and restricted eating
behaviour and ematiation
 psychotic symptoms: delusional thinking,
distorted body image, exaggerated harm
avoidance (i.e. repulsion of eating)
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Neuropathology
 In recovered people with AN, there are
decreased amounts of 5-HT2A receptor sites in
the amygdala, hippocampus, and cingulate
cortex
 This decrease in 5-HT2A receptors is due to
hyperserotonergic activity
 May also explain reduced serotonin metabolites in
the CSF
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Neuropathology
In Bulimia Nervosa there is a general decrease in 5HT levels:
 Serotonergic pathways affects increases satiety
mechanisms
 Evidence of lower levels of 5-HT metabolites in
Cerebral Spinal Fluid
 Lower 5-HT levels promote binging due decrease
in satiety mechanisms
 Comorbidities between BN and other impulse
control disorders (e.g. OCD, depression)
 Low 5-HT levels in forebrain
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