A recent study has revealed that children diagnosed with an early-onset restrictive eating disorder (rEO-ED) exhibit significant changes in brain structure. This research, which analyzed magnetic resonance imaging scans from 174 children under the age of 13, aims to enhance understanding of how these disorders relate to other neurodevelopmental conditions and inform treatment options.
The international team of researchers compared the brain scans of children with rEO-ED to those of 116 children without any eating disorder diagnosis. They sought to identify differences not only among the various types of eating disorders but also to explore potential connections between brain structures and conditions such as obsessive compulsive disorder (OCD).
Study Findings on Brain Structure Variations
The researchers noted that early-onset restrictive eating disorders include a variety of conditions, particularly early-onset anorexia nervosa and avoidant/restrictive food intake disorders (ARFID). They stated, “The impact of rEO-ED on brain morphometry remains largely unknown.” Their findings indicate notable brain structure differences for both early-onset anorexia nervosa and underweight patients with ARFID.
Specifically, children with early-onset anorexia nervosa showed a thinner cortex and increased cerebrospinal fluid, while those with ARFID had reduced surface area and overall brain volume. However, the study’s snapshot nature complicates the analysis of whether these structural variations are causes or consequences of the disorders. Among the children diagnosed with early-onset anorexia nervosa, changes in cortical thickness correlated more closely with body mass index (BMI), suggesting that these neurological differences may result from restrictive eating behaviors.
To further investigate the overlap between restrictive eating disorders and other neurodevelopmental conditions, the team utilized external datasets. They discovered similarities in cortical thickness between early-onset anorexia nervosa and OCD, as well as between ARFID and autism. Surprisingly, there was minimal overlap between anorexia nervosa and autism, or between ARFID and attention deficit hyperactivity disorder (ADHD).
Implications for Treatment and Future Research
The findings highlight the importance of treating early-onset anorexia nervosa and ARFID as distinct disorders, while also recognizing their shared characteristics with other mental health conditions. The researchers concluded, “This multiscale overlap – at the clinical, brain and genetic levels – suggests shared mechanisms underlying psychiatric disorders that are independent of BMI.”
These insights enhance our understanding of the connections between eating behaviors and brain structures, which can guide the development of potential treatments. Current approaches for managing these disorders include a combination of dietary and psychological treatments, notably cognitive behavioral therapy (CBT).
Given the complexity of the relationship between brain function and eating habits, the researchers are eager to continue their investigations. Future studies may involve larger sample sizes and longitudinal tracking of brain changes over time. The research is set to be published in Nature Mental Health in March 2024, marking a significant step forward in the understanding of early-onset restrictive eating disorders.
