Table 2.

Comorbidity rates and conceptual overlap between eating disorders and anxiety-related disorders.

Anxiety-related Disorder	Comorbidity Rates Among those with EDs	Conceptual and/or Symptom Overlap
Specific Phobia	• Up to 32 % of individuals across EDs (Bulik et al., 1997; Godart et al., 2000; Hudson et al., 2007; Ulfvebrand et al., 2015).	• Intense or irrational fears of fatness/weight gain (American Psychiatric Association, 2013) • Pervasive avoidance of food and shape- or weight-related stimuli (e.g., scales; viewing their body) (Pallister & Waller, 2008).
Generalized Anxiety Disorder	• 7-37% in AN (Bulik et al., 1997; Godart et al., 2000; Hudson et al., 2007; Lilenfeld et al., 1998; Ulfvebrand et al., 2015) • 10-55% in BN (Bulik et al., 1997; Hudson et al., 2007; Schwalberg et al., 1992; Ulfvebrand et al., 2015), • over 10% in BED (Hudson et al., 2007).	• Repetitive negative thinking processes, including both worry and rumination, are common in both AN and BN, and the content of this worry may be both general and specific to ED symptoms (Kathryn E Smith et al., 2018; Startup et al., 2013; Sternheim et al., 2012). • Worry predicts EDs longitudinally (Sala et al., 2019; Sala et al., 2018; Sala & Levinson, 2016) • Symptoms of GAD at age 10 may be more predictive of EDs in adolescence than other anxiety-based symptoms (Schaumberg et al., 2018). • Elevated intolerance of uncertainty, positive beliefs about worry, negative problem orientation, and cognitive avoidance are present in clinical and subclinical ED samples; however, comprehensive tests regarding the fit of various GAD models to ED samples have yet to be conducted (Konstantellou et al., 2011; Rawal et al., 2010).
Obsessive Compulsive Disorder	• 33-50% of individuals with EDs (Kaye et al., 2004; Thiel et al., 1995)	• Significant shared genetic risk between AN and OCD (Yilmaz et al., 2018). • Individuals with EDs may have intrusive thoughts about losing control over eating and intrusive images of themselves as fat (Belloch et al., 2016; Garcia-Soriano et al., 2014), with the frequency and emotional disturbance of these cognitions comparable to obsessions in OCD. • Thought-shape fusion, the belief that thinking about or imaging the act of eating a “forbidden” food contributes to weight gain and/or is indicative of moral wrongdoing (Shafran et al., 1999). • Compulsions and repetitive behaviors in EDs aimed at preventing feared weight gain (e.g., compulsive exercising (Meyer et al., 2011), body checking (Mountford et al., 2006), mealtime rituals (Gianini et al., 2015). • Distinct types of obsessive thoughts (e.g., gaining weight uncontrollably; fear of losing control over eating) are predictive of specific behavioral responses (e.g., body checking) and vice-versa (Bailey & Waller, 2017; Levinson, Sala, et al., 2018),
Panic Disorder	• 3-34% of those with EDs and higher than rates observed in the general population (Godart et al., 2000; Hudson et al., 2007).	• Heightened interoceptive awareness (T. A. Brown et al., 2017; Jenkinson et al., 2018), sensitivity (Klabunde et al., 2013; Pollatos et al., 2008), and processing (Berner et al., 2017; Oberndorfer et al., 2013; Strigo et al., 2013) • Gastrointestinal complaints (e.g., early satiety, fullness, bloating, constipation (Sato & Fukudo, 2015)) • Hypersensitivity to, and difficulty tolerating, aversive body sensations are associated with severity of ED symptoms (T. A. Brown et al., 2017). • Elevated anxiety sensitivity (Anestis, Holm-Denoma, et al., 2008; Fulton et al., 2012; Thompson-Brenner et al., 2018). • Attempts to avoid internal experiences and/or difficulty tolerating physical sensations (e.g., gastric sensations) may play a role in ED risk and maintenance (Boyd et al., 2005; Brand-Gothelf et al., 2016; T. A. Brown et al., 2017; Zucker et al., 2013).
Social Anxiety Disorder	• 17-34%, which is greater than rates in the general population (12.1%) (Brewerton et al., 1995; Ruscio et al., 2008).	• BN predicts later onset of SAD (Buckner et al., 2010); EDs and SAD may result from shared vulnerabilities, including social appearance anxiety (the fear of social judgment specifically on one’s appearance) and maladaptive perfectionism (Levinson & Rodebaugh, 2012; Levinson et al., 2013) • Social anxiety commonly presents in individuals with EDs, especially in situations regarding potential social judgment related to appearance and eating in social settings (e.g., restaurants, shopping malls, cafeterias)(Gutiérrez-Maldonado et al., 2010). • Co-occurring symptoms that ‘bridge’ or connect between SAD and EDs include eating in public and feeling nervous about one’s appearance (Levinson, Brosof, et al., 2018; Levinson et al., 2014; Levinson, Zerwas, et al., 2018)
Posttraumatic Stress Disorder	• lifetime PTSD diagnoses among those with EDs range from 12% among individuals with AN, 26% of those with BED, and 45% of those with BN (Hudson et al., 2007)	• Tramna exposure is considered a non-specific risk factor for EDs, with childhood and sexual trauma representing particularly salient risk factors (Smolak & Murnen, 2002; Wonderlich et al., 2001). • Individuals with PTSD and EDs often report emotion dysregulation (Ehring & Quack, 2010; Lavender et al., 2015) and alexithymia, or difficulty identifying emotional experiences (Frewen et al., 2008; Westwood et al., 2017). • ED behaviors, particularly binge eating and purging, may serve a function of numbing or escaping from PTSD symptoms (Mitchell & Wolf, 2016), with a recent cross-sectional network analysis of comorbid PTSD and ED symptoms supporting associations among irritability and binge eating (Vanzhula et al., 2019) • Sexual trauma, in particular, may influence one’s body image (Dansky et al., 1997; Sack et al., 2010) and contribute to a desire to appear less attractive or hide one’s body (which could instigate either weight gain or loss).