New anti-obesity medications: Considerations and future directions in people with concurrent eating disorders

This article is part of a longitudinal series on nutrition and diet.

PS and HJ are the two co-senior authors.

Everybody looks so great. When I look around this room, I can’t help but wonder ‘Is Ozempic right for me?’

– Jimmy Kimmel

The above quote is from Jimmy Kimmel’s opening speech at the Academy Awards in March 2023 as he gazed across the star-studded audience.¹ The fact that such a comment was met with universal laughter suggests widespread public awareness of the effectiveness of semaglutide in promoting weight loss. In Australia, semaglutide 1.0 mg weekly is approved by the Therapeutic Goods Administration (TGA) for the treatment of type 2 diabetes.² Semaglutide 2.4 mg weekly is approved (but not currently available) for chronic weight management in adults with a body mass index of ≥30 kg/m² or ≥27 kg/m² with at least one weight-related comorbidity.² The widespread promotion of semaglutide on social media as a short-term weight loss method (eg ‘#Ozempic’-tagged posts viewed over 250 million times on TikTok),³ has raised concerns over potential non-prescribed use in people with eating disorders. The aim of this viewpoint is to discuss considerations of eating disorders in people seeking treatment for obesity and recommendations for future research.

Glucagon-like peptide-1 (GLP-1) receptor agonists such as semaglutide reduce food intake by acting at GLP-1 receptors in appetite and reward centres in the brain (including the hypothalamus, hindbrain and mesolimbic pathway) to reduce hunger and food reward and increase satiation. They also control blood glucose levels by stimulating insulin secretion in the presence of hyperglycaemia, reducing glucagon secretion and slowing gastric emptying.⁴ Semaglutide (2.4 mg weekly) is the first obesity medication for which weight loss of >10% was achieved in most (69%) clinical trial participants (mean weight loss 15% at 68 weeks).⁵ Regulatory approval for an obesity indication is expected to be sought in 2023 for tirzepatide, a dual GLP-1 and glucose-dependent insulinotropic polypeptide receptor agonist that resulted in a mean weight loss of 21% over 72 weeks in a clinical trial for obesity management.⁶ Both medications are associated with greater improvements in cardiometabolic risk factors (including waist circumference and blood pressure, blood glucose and lipid levels) and health-related quality of life compared with placebo.⁵ Both semaglutide and tirzepatide (as well as all other medications for obesity management) are intended to be used alongside behavioural/lifestyle interventions. Most agents, including semaglutide, are intended for long-term use to maintain weight loss and associated health improvements. Cessation of effective medications for weight management results in loss of effect, often leading to rapid weight regain. Short-term use, and the associated weight rebound, might cause distress in some people, especially in those experiencing eating disorders due to overconcern about body weight and shape, and their control.⁶

Eating disorders, characterised by an overvaluation of body weight and shape in the context of binge eating and/or extreme weight control behaviours, are incorrectly and stereotypically associated with low body weight. In fact, eating disorders of all phenotypes are more common in people with higher weight.⁷ Individuals with eating disorders and higher weight are more likely to seek and be referred to weight loss interventions, including pharmacological interventions, than addressing eating disorder symptoms.⁸ As a result, screening for previously undiagnosed eating disorders and enquiring about body image concerns and disordered eating behaviours, including binge eating, fasting, purging or night eating, is recommended as part of screening and assessment of comorbidities prior to obesity treatment.⁹ The 2022 National Eating Disorders Collaboration (NEDC) guidelines⁹ encourage screening using the five-item Eating Disorder Screen for Primary Care (see Box 1)¹⁰ when patients with a higher weight seek support for weight loss. Although most people will usually experience a reduction in eating disorder symptoms during obesity treatment, a subset might experience the onset of new symptoms.¹¹ Therefore, monitoring for the emergence of disordered eating during obesity treatment is also warranted. For example, loss of control over eating, obsessive behaviours, rigidity (eg rigid calorie counting), greater than expected weight loss, excessive self-weighing and/or weight fluctuations.⁹
 

Approaches to the co-treatment of obesity and eating disorders have been trialled. Specialist programs (eg a Healthy APproach to weIght management and Food in Eating Disorders [HAPIFED] in Australia)¹² combine evidence-based psychological therapy for eating disorders with behavioural weight loss interventions. Although these programs show promise for eating disorder outcomes, they are often not associated with sustained improvement in cardiometabolic health. Research on combined programs that include more effective obesity treatments, such as anti-obesity pharmacotherapy, is needed. There are currently clinical trials in progress investigating the impacts of 2.4 mg semaglutide coupled with behavioural weight loss on eating disorder symptoms in people with obesity (https://clinicaltrials.gov/ct2/show/NCT05548647). We encourage more research in this space, including the specific examination of the effects of obesity medications on diagnosed binge eating disorder with concurrent obesity. People with both obesity and eating disorders have complex medical needs requiring multidisciplinary care. Improved linkages and referral pathways between obesity and eating disorders are strongly needed to facilitate effective concurrent treatment of both conditions.