Study Finds First Genes Linked To Anorexia, Offers 'Hope' To Sufferers
WARNING: The following story discusses anorexia and mental illness and may be triggering for some individuals.
Lara Swinsburg has always wondered what was different about her mind that saw her succumb her to anorexia nervosa.
The 22-year-old university student has managed the eating disorder for six years, after she was first diagnosed in 2013.
"It started in 2012 when I lost my first job. That made me feel really worthless, and I started using food and exercise as my way to deal with it," Swinsburg told 10 daily, of a highly personal struggle that she hid from her family.
Now, with ongoing treatment and family support, she feels like a different person. But she hasn't stopped wondering.
"I've had cousins who've dealt with similar issues; or friends who may get similar thoughts. But it doesn't affect them in the same way -- they don't go to the same extremes that I go to," she said.
What's different in people when today in society, food, weight and exercise is so prevalent?
Researchers are drawing closer to understanding why after identifying the first eight genes linked to the serious disorder.
The results of the largest-known, international study -- published in the Nature journal on Tuesday -- found its origins appear to be both psychiatric and, unexpectedly, metabolic.
"This was a surprise to us," Professor Nicholas Martin told 10 daily.
Anorexia nervosa is a serious and complex disorder characterised mainly by a low body-mass index (BMI), an intense aversion to weight gain and an unwillingness to recognise the seriousness of a low body weight.
It affects up to four percent of women and 0.3 percent of men and has a higher death rate than other psychiatric disorders.
Senior Scientist and head of the QIMR Berghofer Medical Research Institute's Genetic Epidemiology laboratory, Martin said researchers were caught off-guard by the new findings.
"We hadn't expected that at all -- we thought it would be a completely psychiatric disease," he said.
Up until now, Martin said the focus of the disorder has been purely psychiatric.
"It has been assumed that the obvious constant of anorexia -- body size and metabolism -- are all the flow-on effects of the psychiatric condition. But it seems it is not that simple," he said.
Almost 17,000 people with lived experience of the disorder -- including around 3000 Australians and New Zealanders -- took part in the study.
Researchers compared their DNA to that of 55,525 controls across 17 countries, identifying eight genetic markers associated with the disorder.
They found genetic correlations with certain psychiatric disorders -- such as obsessive compulsive disorder, depression and anxiety -- along with metabolic traits that were not due to genetic effects that influence BMI.
"At the moment, it's looking like a 50-50 split," Martin said.
Researchers hope the results will encourage a "reconceptualisation" of the disorder as metabo-psychiatric.
"I don't think we are completely clear what that means yet, but I think it will lead to a change of direction into research of this condition -- to try and understand what this large, genetic metabolic component actually means," he said.
Martin said the genetic information could not only help to identify those at greatest risk of developing the condition, but to reduce stigma.
“By showing the role genetics plays in anorexia nervosa we should be able to remove any remaining stigma associated with the condition for patients and their families -– especially parents," he said.
The added role of metabolism could help to influence treatment, according to Cynthia M. Bulik, Principal investigator and Professor in the Department of Psychiatry at the University of North Carolina School of Medicine.
"Our findings strongly encourage us to also shine the torch on the role of metabolism to help understand why individuals with anorexia frequently drop back to dangerously low weights, even after therapeutic renourishment,” Bulik said.
“A failure to consider the role of metabolism may have contributed to the poor track record among health professionals in treating this illness.”
For Swinsburg, the findings offer "comfort and hope".
"This is something that affects so many people that we don't even realise and we don't really know what causes it," she said.
"It's comforting to know the professionals are working to trying and figure it out."
Researchers are encouraging anyone with lived experience of anorexia nervosa, bulimia or other eating disorders to sign up to the next stage of the study.
"We know the first eight genes now; that's the most exciting thing for us. We are confident there will be many more," Martin said.
Featured image: Supplied
Anyone needing support with eating disorders or body image issues is encouraged to contact Butterfly’s National Helpline on 1800 ED HOPE (33 4673). For urgent support, call Lifeline on 13 11 14.