10- Eating Dx Flashcards
Anorexia Nervosa DSM-5 Dx
- Restriction of energy intake leading to a significantly low body weight that is less than minimally expected/normal
- Intense fear of gaining weight or becoming fat, or beh to prevent weight gain
- Distortion in experience of body weight/shape or undue significance
- Severity specified based on BMI
Two subtypes: Restricting & Binge eating/purging
=> Body Mass Index (Weight (kg) divided by height (m) squared)
DSM severity specifiers:
- Mild: >17
- Moderate: 16-17
- Severe: 15-16
- Extreme: <15
Some challenges: “Normal weight” differs between men and women and at different ages, Onset of AN during growth periods
*Ego-syntonic Dx: Low weight in AN is ego-syntonic (pleasure/gratification) => The eating disorder is often highly valued and important to the individual ex: reflects self-control
Positively reinforced by others
- This affects clinical intervention outcomes! => High drop out rates, Want to feel better, but don’t want to gain weight
Food-Related Beh and Subtypes
- Restrict amount of food eaten
- Avoid high calorie foods
- “Forbidden foods”
- Secrecy and hiding of food
- Ritualistic beh
- Consuming lots of water
Restricting Subtype => Low weight is achieved primarily through dieting, fasting, and/or excessive exercise only
Binge Eating/Purging Subtype => Not only restricts, but also engages in binging and purging
Common purging beh:
- Self-induced vomiting
- Laxatives
- Diuretics
- Enemas
*Objective vs. subjective binge =>
- Difference: amount of food
- Common: loss of control & distress
Disturbances in Body Weight/Shape
- Perception isn’t accurate
- Fail to recognize low body weight as a prob
- Self-worth based on weight/shape (affects other areas too)
- Body Checking Beh
Bulimia Nervosa DSM-5 Dx
- Occurs once per week for at least 3 months
- Recurrent episodes of binge eating => Large quantity and Lack of control
- Inappropriate compensatory beh ex: self-induced vomiting, fasting
- Self-evaluation overly influenced by body weight/shape (don’t have “Perception isn’t accurate” and “Fail to recognize low body weight as a prob”)
- Severity specified on number of compensatory beh/week
Typical Characteristics
- Typically in the normal weight range => Compensatory beh are not effective at producing significant weight loss relative to calories consumed
- Vicious cycle: Restriction, Binges often with “forbidden foods”, Purge to relieve physical discomfort and avoid weight gain
Restriction Study
N = 133 women with BN and Ecological momentary assessment about binge eating episodes and caloric restriction
- Restriction increased likelihood of binge eating
Supports therapy models that aim to reduce dietary restriction to improve BN symptoms
Beh vs Cognitive Restriction => Orthorexia
Binge-Eating Dx DSM-5 Dx
- Recurrent episodes of binge eating => Large quantity and Lack of control
Three or more of the following:
- Eating quickly
- Eating until uncomfortably full
- Eating large amounts when not physically hungry
- Eating alone due to embarrassment over large amounts of food
- Feeling disgusted, depression, or guilty after
*New addition to DSM-5
Typical Characteristics
- No compensatory behaviors
- Less restraint compared to AN and BN
- Often overweight or obese => If in normal weight range, likely to be younger
- Overevaluation of shape and weight is NOT a diagnostic feature => But have concerns comparable to those with BN (and more than people without BED)
Validity of Dx Classification
Are these truly “distinct disorders”? => Lots of shared clinical features ex: BN= AN - BP type without low BMI, BED = BN without compensatory beh
Issue: Diagnostic crossover (very frequent, bi directional) => ex: AN with binge switch to BN BUT no cross over from an restricting and BED
Rethinking DSM Classification:
- Viewed as a spectrum, rather than as separate distinct categories based on severity => ex: AN most severe
- Or spectrum of beh (ex: most severe = BN with purging beh and Least severe: BED)
- RDoC: Examine core underlying features that characterize mental disorders more broadly => emotion regulation deficits
Transdiagnostic View => Everything stems from “Over-evaluation of shape and weight and their control”
Epidemio
Lifetime prevalence estimates:
- AN: <1%
- BN: 1%
- BED: 2%
Prior to DSM-5, high rates of “other” ED = 2.37%
- Rates highest among White women
- Presumed protective factor among Black women
- Subclinical eating disordered beh and attitudes are HIGHLY common
Gender Differences
- Consistently much higher prevalence among women
- Used to think 10-15:1 (F:M) but Now 3:1
- Bias in DSM criteria => Women: drive for thinness, Men: drive for muscularity
- Sociocultural factors => Media communicates weight ideals more for women than men and as a result, women place more emphasis on weight
Sexual Orientation
- Some studies find that gay men have higher ED rates (vs. heterosexual) *inconsistent findings
- Two studies have also found that men with eating dx are not more likely to identify as gay
- Effects may be accounted for by level of body dissatisfaction (third variable!)
- No effects of sexual orientation for women
High Comorbidity
- Depressive dx
- Anxiety dx
- OCD
- Substance abuse => Except not in AN-restricting type
- Personality disorders: OCPD / Perfectionism (AN) * BPD (BN) *Might predate ED
Course and Med Complications
Changes Over Time
- Increases in eating dx rates in the 20th century => Better awareness of dx? Or more people affected?
-Likely peaked in 1990s but now more stable rates - BUT, evidence of continued increase in subthreshold eating disordered beh and attitudes
Course
Age of onset:
- AN: 16-20 years old
- BN: 21-24 years old
- BED: 30-50 years old
*Highest mortality rate of any psychiatric dx (specifically AN) because of Starvation/malnutrition and Suicide
- Approx. 50% show reduction in sx with tx => Similar if non-treatment seeking
- High risk of relapse
- Even when no longer meeting dx criteria, likely still have issues with food and body image
Medical Complications
- Physical symptoms: Thinning hair, dry skin, “lanugo”, jaundice, Weakness, fatigue, Purging causes damage to teeth and fingers, swelling in cheeks, Amenorrhea
- Increased risk of osteoporosis
- Arrythmias (irregular heartbeats) => Due to low levels of potassium
- Problems exacerbated with laxative use and purging ex: dehydration, electrolyte imbalance (hypokalemia), damage to bowls and GI tract
Biological Factors
Genetic Vulnerability
- Eating dx run in families
- Relatives are at increased risk of ED => But also increased risk of other dx
Review of twin studies found:
- AN: 48-76% heritable
- BN: 50-83% heritable
- BED: 41%
*No replicable effects with specific genes
Family Factors
- Family environments that are critical about weight/shape and focus on appearance themes in the household have increased risk of ED
Children of mothers with ED have increased risk: Genetic factor But also lots of environmental contributors:
- Mother may make comments about daughter’s weight and shape
- Modeling of dieting beh and concern about appearance
- Affects ability to feed child in non-restrictive way
Neurotransmitters: Serotonin => Serotonin is made from tryptophan, which can be produce from food
- Dysregulation of serotonin system in EDs => AN tend to show low levels compared to controls but find higher levels in AN and BN after recovery (maybe increased lvls
= risk factor) - Gender differences stemming from differences in serotonergic functioning?
- Mostly correlational data – alterations in serotonin may be due low weight or malnutrition
- Like we saw with MDD and OCD, assume that because SSRIs work (in BN) then serotonin must play causal role
Socialcultural Factors
The Thin Ideal
- Western society pressures women to achieve an unrealistic and unattainable “thin ideal” => Messages directed predominantly toward women
- The thin ideal woman portrayed in the media is typically 15% below the average weight of women
- Steady decrease in size of “ideal” woman in mass media => And rates of obesity are on the rise
Evidence for the Effects of Thin Ideals:
Experimental evidence:
- Randomly assign individuals to view images of thin ideals (ex: magazine or TV ad) vs. neutral images
- Less body satisfaction
- Allows for causal inferences but often lacking external validity
Correlational evidence:
- More frequent exposure to thin ideals (ex: fashion magazines or TV) associated with greater body dissatisfaction and ED symptoms
- Suggests that experimental evidence generalizes outside the lab *But, possibility of reverse causality
=> Meta-analyses find a small to moderate effect of thin ideal exposure on body image and eating dx sx
- Effects only significant for women
- More pronounced effect among women who report pre-existing body dissatisfaction
- No difference between types of media consumption (ex: TV, ads, music videos) *Even just brief exposure!
Fiji Study and Social Media
Fiji previously had low prevalence of ED => Only one case by mid-1990s (Media-naïve population) But, then introduction of Western television in 1995
Quasi-experimental, naturalistic design and assessed Fijian women three years later (1998)
- Increases in eating disordered attitudes and beh
- In 1995, 0% of participants reported self- induced vomiting to control weight vs 11.3% in 1998
- 69% reported dieting
- 74% reported feeling “too big or fat”
- 77% reported that TV influenced their body image => Reported desire to lose weight to look like the Western TV characters
Social Media
- Positive correlation between general social media use and appearance concerns
- Experimentally manipulating exposure to “thin ideal” social media posts increases negative mood and body dissatisfaction
- One longitudinal study found social media use predicted negative body image, but not vice versa
- Appearance-related social comparisons =>Mediates the relationship between social media use and body image (Comparing to peers may be especially influential)
Psychological Factors
Internalization of the Thin Ideal
- Believed to be causal risk factor for ED
- The extent to which an individual cognitively “buys into” socially defined ideals of attractiveness
- Leads to body dissatisfaction and negative affect since this ideal is unattainable for most women and in turn, results in eating-related beh to change this (ex: dieting) and thus increase risk of ED
Cognitive Theories of ED
Develop schemas focused on weight and its implications for the self => Self as thin vs Self as fat *SEE PPX!
Info Processing Biases
- Weight-related schemas influence automatic info processing
- Implicit attitudes: Pro-thin/anti-fat bias (Correlates with BMI)
- Attentional bias: Food, Body, Socially threatening faces
- Memory bias
Trait Impulsivity => Negative Urgency
The tendency to engage in rash action in response to negative affect aka “It is hard for me to resist acting on my feelings”
- Trait levels of NU specifically are positively correlated with BN symptoms *Over and above negative affect
- Longitudinal study showed NU prospectively predicted increased risk for binge eating in college students
- Transdiagnostic risk factor for binge eating => Not all ind with high NU will develop binge eating ex: alcohol/substance use, depression
- Interacts with eating-disorder specific risk factors => Appearance pressures, thin-ideal internalization, body dissatisfaction
*High neg urgency + high low body dissatis = highest risk
Other Individual Risk Factors
- Negative body image
- Dieting
- Low self-esteem
- Identity problems
- Negative affect
Psychological Factors - Escape Theory BED, Study and Feeling Fat
“Binge eating may arise as part of a motivated attempt to escape from self- awareness”
- Presence of high standards (ex: goals, expectations, ideals)
- Compare self against these standards and fall short
- Awareness of self’s shortcomings and creates negative affect
=> Then seek to escape aversive self-awareness, how?
- Through shift in attention: Cognitive narrowing effect, Focus away from higher-level meaning (ex: self as failure), Focus toward positive sensations associated with eating
- Key prediction then would be that negative emotion predicts onset of binge eating => And individuals with more emotion regulation difficulties should be more likely to binge eat
Emotion Regulation BDE Study with women (n=131) with BN while using Ecological momentary assessment (EMA) design
- Increases in negative emotions reliably preceded binge and/or purge event
- Followed by decreases in negative emotions after binge and/or purge event => Recall negative reinforcement
Feeling Fat => May play key role as a maintaining factor in ED
- Sensation of carrying excess fat which fluctuates over time *Not associated with actual BMI
- “Feeling fat” predicts eating disordered beh (ex: dietary restraint) and concerns => Over and above negative affect and body dissatisfaction
But, “fat” is not an actual emotion. What underlies this?
- Body displacement hypothesis (neg emotion and displace it on body = feel fat)
- Depressed mood
Tx
Psychopharmaco
- Generally, not much success in treating AN with medication
- BN often treated with antidepressants => Due to comorbid depression (not as effective as empirically-based psychotherapies)
- BED sometimes treated with Bupropion (Wellbutrin) to Reduces cravings *Not associated with weight gain
*CBT-Enhanced => Most empirically supported intervention (more successful with BN/BED (vs. AN)
- Psychoeducation of CBT formulation target compensatory beh then dieting/weight-control beh
- Regular pattern of eating: Reduce restriction, binging, purging, Aim for 3 meals + 2 snacks (without overcompensating), Use of “food diaries”
- Target cognitions about food, weight, shape
Nutrition
- For AN, priority is to restore patient to a medically healthy weight => This can improve a lot of cognitive and emotional sx
- Provision of nutritional counselling (ex: role of dietitians)
- Meal support => eat lunch with patients in day programs, snacks in group/individual therapy sessions
Family Intervention => Gold standard when working with adolescents
*Multidisciplinary approach => Psychotherapist, psychiatrist, dietitian, nurse, physician
Obesity
Not classified as an eating disorder in DSM
Prevalence: 36% of US adults are overweight and 34% are obese => The “norm” is NOT in the “normal” weight range and also, increasing over time (“obesity epidemic”)
Increased risk for many medical health problems
Risk Factors => Person’s BMI is, at least in part, influenced by genetic factors, Family attitudes about weight and food, Food as an emotion regulation fct
- Genetics
- Metabolism
- Comorbidities
- Eating Beh
- Activity habits
- Health knowledge
- SES/Neighborhoods
- Food policy
- Schools
