Chapter 13 Feeding and Eating Disorders

Eating Disorder (ED) Categories Anorexia nervosa (AN) Bulimia nervosa (BN) Binge Eating disorder (BED)

Anorexia Nervosa: DSM-5 Restriction of intake relative to requirements needed to maintain body weight at or above a minimally normal weight for age, sex, developmental trajectory, and physical health Intense fear of gaining weight or becoming fat, or persistent behavior that interferes with weight gain, even though at a significantly low weight

Disturbance in how weight or shape is experienced Undue influence of body weight or shape on self-evaluation Denial of the seriousness of the current low body weight Restricting type: Does not regularly engage in binge eating or purging behavior Binge Eating/purging type: Has regularly engaged in binge eating or purging behavior Anorexia Nervosa: DSM-5 cont.

Recurrent episodes of binge eating characterized by both of the following: – Eating, in a discrete period of time (e.g., within any 2-hour period), an amount of food that is definitely larger than most people would eat during a similar period of time and under similar circumstances – A sense of lack of control over eating during the episode Recurrent inappropriate compensatory behaviors in order to prevent weight gain, such as self-induced vomiting; misuse of laxatives, diuretics, or other medications; fasting or excessive exercise Bulimia Nervosa: DSM-5

Binge eating and inappropriate compensatory behaviors average at least twice a week for 3 months Self-evaluation is unduly influenced by body shape and weight The disturbance does not occur exclusively during episodes of anorexia nervosa Bulimia Nervosa: DSM-5 cont.

Recurrent episodes of binge eating An episode of binge eating is characterized by both of the following: – Eating, in a discrete period of time (e.g., within any 2-hour period), an amount of food that is definitely larger than most people would eat in a similar period of time under similar circumstances – The sense of lack of control over eating during the episode Episodes include three (or more) of the following: – Eating much more rapidly than normal – Eating until feeling uncomfortably full – Eating large amounts of food when not feeling physically hungry – Eating alone because of being embarrassed by how much one is eating – Feeling disgusted with oneself, depressed, or very guilty after overeating Binge Eating Disorder: DSM-5

Marked distress regarding binge eating is present The binge eating occurs, on average, at least once a week for 3 months The binge eating is not associated with the regular use of inappropriate compensatory behavior (e.g., purging, fasting, excessive exercise) and does not occur exclusively during the course of anorexia nervosa or bulimia nervosa Binge Eating Disorder: DSM-5 cont.

Diagnostic Considerations Important to consider endophenotypes of eating disorders to inform eating disorder classification – More specific to AN: perfectionism, obsessionality, anxiety, harm avoidance, and low self-esteem – More specific to BN: higher novelty seeking, higher impulsivity, lower self-directedness, and lower cooperativeness – Nearly 80% of patients experience comorbid disorders such as anxiety disorders, depressive disorders, substance use disorders, and personality disorders

Epidemiology Lifetime prevalence for individuals over 18 – AN Women: 0.9% Men: 0.3% – BN Women: 1.5% Men: 5% – BED Women: 3.5% Men: 2%

Epidemiology cont. Sex ratio for AN is approximately 9:1, women to men The peak age of onset for AN is between 15 and 19 years New-onset cases in mid- and late-life have been reported Presentations in children are increasing

Psychological Assessment The general goal of psychological assessment is to elicit information that: – Accurately describes symptomatology – Accurately characterizes diagnostic profile – Indicates appropriate treatment recommendations

Psychological Assessment cont. Structured interviews – Diagnostic Interview Schedule – Composite International Diagnostic Interview – Eating Disorder Examination Self-reports – Eating Disorder Inventory – Eating Disorder Examination— Questionnaire – Many others

Medical Assessment Although all ED patients require medical monitoring, low-weight patients, individuals with purging behaviors, and obese individuals with binge-eating behaviors are typically at greatest risk for medical complications: – Low weight associated with sudden cardiac death – Purging associated with electrolyte imbalance – BED associated with Type II diabetes and other disorders independent of obesity

Etiology Common risk factors across eating disorders: – Female sex – Race or ethnicity – Childhood eating and gastrointestinal problems – Elevated concerns about shape and weight – Negative self-evaluation – Prior history of sexual abuse and other adverse events – Presence of additional psychiatric diagnoses

Etiology cont. Contemporary understanding of eating disorders – Both genetic and environmental factors in causal models – Previous overemphasis on sociocultural factors (particularly social pressures toward thinness) ignore the fact that only a fraction of individuals exposed to these factors develop eating disorders – Individuals who are more genetically predisposed to eating disorders are those who are more vulnerable to environmental triggers of illness

Etiology: Genetic Factors Anorexia nervosa – Family studies Familial nature of AN is well-established – First-degree relatives of patients with AN are 11 times more likely to have AN during their lifetime than first-degree relatives of individuals who have never had AN – Twin studies Twin studies have yielded heritability estimates between 28% and 74% for AN – Molecular studies Promising evidence for genes related to mood regulation, the hedonic reward system, and appetite

Etiology: Neuroanatomy and Neurobiology Brain structural abnormalities – CT and MRI Cerebral activity – PET, SPECT, fMRI Neuropeptides Monoamines – Serotonin (5-HT) – Dopamine (DA) – Norepinephrine (NE)

Learning, Modeling, and Life Events Life events research is fraught with methodological challenges – Some evidence to suggest that individuals with BN and BED were more likely to experience certain stressful life events the year prior to the beginning of their illness Distress Tolerance – Emotion regulation difficulties have long been identified in affected individuals and across eating disorder subtypes

Racial/Ethnic Considerations Risk for AN and BN is generally lower for African American women than White women Risk for binge eating and BED may be equal to, or possibly even greater, in African American women Rates of seeking treatment are lower in African Americans Rates of eating disorders in Latinos suggest prevalence rates similar to Whites

Course and Prognosis Highest risks of premature death from both natural and unnatural causes are from eating disorders, particularly AN (and SUDs) Medical complications – Reproductive problems Treatment – Currently, no medications are effective in the treatment of AN – Cognitive-behavioral therapy – Interpersonal therapy