Brain Imaging Studies Reveal Neurobiology of Eating Disorders

The UC San Diego researchers have used the new information to create new treatment strategies, including psychoeducation – teaching patients why symptoms occur and how to more effectively cope.

Bulimia has gained importance in the past 30 years. In the United States approximately 25 million people are struggling with ‘Binge eating disorder.’ It is also estimated that almost 10 million females and 1 million males are fighting a life-and-death battle with other eating disorders such as Anorexia or Bulimia and only 6% of people suffering from Bulimia receive mental health care.

This disorder is 10 times more common in females than in males.

The prevalence of Bulimia Nervosa among women aged between 16-40 years is reported to be around 1-3%.

It is seldom seen in men.

This is a condition that has been recognised only in the developed countries.

Statistics of Bulimia show a dramatic increase in recent years, especially among young women, between the ages of 15-24.

“Many patients have described finally feeling a wave of relief after learning that the anxiety they experience is not their fault, but partly due to how their brain is responding to food,” said Kaye. “Understanding why their eating disorder is driving them to restrict allows them to better target their anxiety around meals. Strategies such as developing routines before meals have shown promise in reducing the anticipatory anxiety leading up to meals and food restriction.”

The eating disorders anorexia nervosa (AN), bulimia nervosa (BN), binge eating disorder and allied diagnoses such as eating disorder not otherwise specified are common, complex psychiatric disorders with a significant genetic component. Aetiology is unknown, but both phenotypic characteristics and genetic factors appear to be shared across these disorders, and indeed patients often change between diagnostic categories. Molecular studies have attempted to define genetic risk factors for these disorders, including case-control and family-based candidate gene association studies and linkage analysis of multiply affected nuclear families. These have used both clinical diagnoses and eating disorder-related intermediate phenotypes such as drive-for-thinness or body dissatisfaction. Candidate gene studies have focussed on neurotransmitter and neurodevelopmental systems [e.g. serotonergic, opioid, cannabinoid and dopaminergic receptors, and brain-derived neurotrophic factor (BDNF)], appetite regulatory peptides and their receptors [leptin, ghrelin, agouti-related protein (AgRP), melanocortin receptors, neuropeptide Y], energy balance systems (e.g. uncoupling proteins), genes implicated in obesity (e.g. FTO) and sex hormone systems (e.g. oestrogen receptors), either identified on the basis of their function alone or as positional candidates from linkage analysis. Of these studies, linkage analysis implicates 1p33-36 for AN, 1q31.3 for quantitative behavioural traits related to anorexia and 10p14 for BN, as well as other behavioural phenotypes across both disorders. Candidate gene association has implicated BDNF, delta 1 opioid receptor (OPDR1) and AgRP. More recently, with the advent of genome-wide association studies (GWAS), analysis with microsatellite markers has implicated novel candidate loci for AN at 1q41 and 11q22, and further GWAS results are expected in the near future.

Kaye said the brain-based therapy also benefits families of patients with eating disorders.

“Through a better understanding of their family member’s eating disorder and its causes, family members have found comfort and hope with a ‘road map’ guiding them through the recovery.”

###

Source Newsroom: University of California, San Diego Health Sciences

Page 2 of 21 2

Provided by ArmMed Media