Eating disorders Flashcards
Define eating disorders
- Definite disturbance in eating habits or weight control behaviour;
- Core ED features ( disturbed eating + overevaluation of the control of eating, weight, shape) resulting in clinically significant impairment in health/psychosocial function;
- Not secondary to any general medical or psychiatric condition.
Describe how EDs are classified
classified by the DSM-V as:
- anorexia nervosa
- bulimia nervosa
- binge eating disorder,
- otherwise specified feeding/eating disorders (OSFED) -c.f. DSM-IV eating disorder not otherwise specified (ED-NOS
What is the lifetime prevalence of any ED?
5%
What is AN chcaracterised by?
relentless self-starvation with dramatic physiological and psychological effects, especially critically low body weight; AN is associated with low rates of recovery (Berkman et al., 2007), and has the highest mortality rate of any psychiatric disorder (Arcelus et al., 2011); [however, it has a lower incidence than bulimia nervosa]
To be diagnosed with AN, a person must display…
- Persistent restriction of energy intake leading to significantly low body weight (in the context of what is minimally expected for age, sex, developmental trajectory and physical health)
- Either an intense fear of gaining weight or becoming fat, or persistent behaviour that interferes with weight gain (even though significantly low weight)
- Disturbance in the way one’s body weight or shape is experienced, undue influence of body shape and weight on self-evaluation, or persistent lack of recognition of the seriousness of the current body weight
What are the subtypes of AN?
Restricting type:
- during the last three months, the person has not engaged in recurrent episodes of binge eating or purging behaviour (ie., self induced vomiting or misuse of laxatives, diuretics or enemas)
Binge/purge type:
- during the last three months, the person has engaged in recurrent episodes of binge eating or purging behaviour (ie., self induced vomiting or misuse of laxatives, diuretics or enemas)
Prevalence of AN
0.3% in teenage girls
Incidence of AN
90% female, 19 cases in females and 2 in males per 100,000 per year
Describe BN
- Recurrent binge-eating – episodes of uncontrolled overeating at least > weekly > 3 m
- Extreme weight control behaviour – self-induced vomiting, laxative misuse, extreme exercise, strict dieting
- Over-evaluation of shape and weight
- Diagnostic criteria for anorexia nervosa not met (e.g. not underweight, possibly overweight) - makes it more difficult to diagnose
What can BN vomiting cause?
Electrolyte imbalances and cardiac dysrhythmias
Which of AN and BN has a greater incidence?
BN
Prevalence of BN
1-2% in 16 to 35 yr olds
Incidence of BN
Mostly female, 29 cases in females and 1 in males per 100,000 per year
Mortality rate and percentage with chronic illness with AN
10-15% mortality rate
Chronic illness in 50%
When are the peak onsets of AN and BN?
Adolescent/ young adult
Describe binge eating disorder
- Recurrent episodes of binge eating > weekly for > 3 months
- Causes impairment and / or distress
- No compensatory behaviours
- No over evaluation of control of eating, weight and shape
Describe onset of BED
Later onset
50% binge eat before dieting begins
Around 65% are morbidly obese
Describe incidence of BED
more balanced distribution between men and women - still more frequent in women (c.f. BN and AN which are mostly women)
Describe otherwise specified feeding/eating disorder
Eating disorders of clinical severity that do not conform to the diagnostic criteria for anorexia nervosa or bulimia nervosa, or atypical forms (comparable to ED-NOS in DSM-IV).
Describe temporal movement between EDs
It is polarised - more common to move from AN to BN rather than from BN to AN