Anorexia nervosa is a serious psychiatric disorder characterized by an abnormally low body weight, an intense fear of gaining weight, and a distortion in body image and self-perception. Individuals with anorexia nervosa restrict food intake, often compulsively over-exercise, and develop unusual eating rituals, while denying that their weight loss or unusual behaviors are problematic. The disorder has the highest mortality rate of any psychiatric illness.
Giles, S., Hughes, E. K., Castle, D., Jenkins, Z., Phillipou, A., Rossell, S., Urbini, G., Fuller-Tyszkiiewicz, M. & Krug, I. (2023). A new network analysis model in anorexia nervosa patients based on self‐reported eating disorder symptoms, psychological distress, and cognitive flexibility. British Journal of Clinical Psychology. https://doi.org/10.1111/bjc.12451
Key Points
- The study found that in people with anorexia nervosa (AN), weight/shape concerns and eating/dietary restraint had the strongest association, indicating they are closely interrelated symptoms.
- Weight/shape concerns also had a strong connection to psychological distress (depression and anxiety).
- Cognitive flexibility was negatively associated with eating concerns/dietary restraint and psychological distress.
- The findings highlight the importance of addressing weight/shape concerns, eating habits, and psychological distress in AN treatment.
Rationale
AN is a severe disorder with high mortality and often involves obsessions related to eating, weight and shape (American Psychiatric Association, 2013).
AN also commonly co-occurs with anxiety and depression, which are linked to poorer treatment outcomes (Fewell et al., 2017). However, the connections between eating disorder (ED) symptoms, anxiety, depression, and related cognitive factors are not well understood (Elliott et al., 2020).
This study aimed to clarify these relationships by using network analysis to map the associations between ED symptoms, depression, anxiety, and cognitive flexibility in people with AN.
Method
Participants completed standard self-report measures of depression, anxiety, cognitive flexibility, weight/shape concerns, and eating disorder symptoms.
A network analysis approach was used to map the connections between all variables at the symptom level. The expected influence statistic was calculated to determine the relative importance of each symptom in the network.
Sample
The sample comprised 193 (95.6% female) treatment-seeking individuals diagnosed with AN, with an average age of 26.89 years (SD = 9.45).
Statistical Measures
Network analysis was utilized to visually map the associations between symptoms at the node level. The expected influence statistic determined the relative importance of each node in the network.
Results
The network analysis showed the strongest connections were between:
- Weight/shape concerns and eating/dietary restraint
- Weight/shape concerns and psychological distress Cognitive flexibility had negative partial correlations with eating/dietary restraint and psychological distress. There was also a minor direct link between eating concerns and psychological distress.
Insight
The findings illustrate overlapping relationships between shape/weight obsession, disordered eating, and psychological distress in AN, highlighting the critical role these domains play together.
Surprisingly, cognitive flexibility did not connect directly to weight/shape concerns but had negative ties to eating habits and distress. This suggests that improving cognitive flexibility could help break cycles of restrictive eating and distress.
The presence of a minor direct link between eating issues and distress also indicates they likely mutually reinforce each other.
Overall, the study sheds light on how core AN symptoms and common comorbidities interrelate.
Weight/shape concerns appear central, highlighting the importance of addressing body image distortion. The patterns also underline eating behaviors and distress as key interlinked factors. Improving cognitive flexibility may be beneficial in targeting both.
Strengths
This study had several key methodological strengths:
- The sample comprised 193 treatment-seeking individuals diagnosed with anorexia nervosa, providing a large clinical sample to study symptom interrelationships.
- The study utilized well-validated clinical measures to assess all symptom domains of interest. This helps ensure an accurate mapping of how these core constructs interrelate.
- This was the first study to date that utilized network analysis techniques to visually map the associations between eating disorder symptoms, common comorbidities, and related cognitive traits at a granular, symptom level. This allows for novel insights into how symptoms group together and interact that may inform targets for intervention.
- Harnessing computational approaches provides an unbiased, data-driven way to shed light on the complex relationships between psychiatric symptoms rather than relying on clinical intuition alone. This is especially valuable in elucidating symptom connections in heterogeneous conditions like AN that vary across patients.
- Calculating centrality metrics like expected influence provides vital information about the importance of specific nodes within the broader network structure. This grants clues as to which symptoms may play an outsized role in linking other components of the psychopathology network together.
Limitations
While the study had many strengths, some limitations should be noted:
- The cross-sectional, observational nature of the study design precludes causal conclusions. While the connections between nodes depict how symptoms group and interact at one point in time, inferences cannot be made regarding temporal precedence or causal relationships driving observed patterns.
- All measures were based on self-report. While necessary to directly probe cognitive traits like cognitive flexibility, self-report data can be influenced by recall biases, impression management, and current state effects.
- The predominance of females in the sample (95.6% female) restricts the generalizability of the results to males with AN. Network connectivity patterns may potentially differ across genders.
- Information on the duration of illness and whether comorbidities predated the eating disorder was not available. Accounting for illness chronicity and the onset of different symptoms could further enrich network models of the illness course.
- Though one of the largest of its kind, the sample originated from a single specialist treatment center. Larger collaborative multi-site efforts could produce more representative findings and test reproducibility.
Implications
- This study highlights the critical importance of addressing weight/shape concerns, disordered eating behaviors, and distress in AN treatment.
- Improving cognitive flexibility may help break cycles of restrictive eating and distress.
- Longitudinal research is needed to establish causal/temporal relationships.
- Findings argue for targeting body image distortion early in AN interventions.
References
Primary reference
Giles, S., Hughes, E. K., Castle, D., Jenkins, Z., Phillipou, A., Rossell, S., Urbini, G., Fuller-Tyszkiiewicz, M. & Krug, I. (2023). A new network analysis model in anorexia nervosa patients based on self‐reported eating disorder symptoms, psychological distress, and cognitive flexibility. British Journal of Clinical Psychology. https://doi.org/10.1111/bjc.12451
Other references
Arcelus, J., Mitchell, A. J., Wales, J., & Nielsen, S. (2011). Mortality rates in patients with anorexia nervosa and other eating disorders. A meta-analysis of 36 studies. Archives of General Psychiatry, 68(7), 724–731. https://doi.org/10.1001/archgenpsychiatry.2011.74
American Psychiatric Association. (2013). Diagnostic and statistical manual of mental disorders (5th ed.). https://doi.org/10.1176/appi.books.9780890425596
Elliott, H., Jones, P. J., & Schmidt, U. (2020). Central symptoms predict posttreatment outcomes and clinical impairment in anorexia nervosa: A network analysis. Clinical Psychological Science, 8(1), 139-154. https://doi.org/10.1177/2167702619865958
Fewell, L. K., Levinson, C. A., & Stark, L. (2017). Depression, worry, and psychosocial functioning predict eating disorder treatment outcomes in a residential and partial hospitalization setting. Eating and Weight Disorders-Studies on Anorexia, Bulimia and Obesity, 22, 291-301. https://doi.org/10.1007/s40519-016-0357-6
Keep Learning
Here are some suggested Socratic discussion questions about this paper for a college class:
- Does addressing body image distortion directly lead to sustained improvement in disordered eating behaviors and psychological distress? Why or why not?
- Could enhanced cognitive flexibility precede and contribute to distortions in body image perception? What mechanisms might be at play?
- How might anxiety, depression, and disordered eating mutually maintain each other over time? What does the temporal sequence look like?
- Would the results differ across AN subtypes or demographic factors like gender or ethnicity? Why or why not?
