New Zealand scientists are calling for volunteers either living with, or having recovered from anorexia nervosa, to enrol in the world’s largest and most rigorous genetic investigation into the illness.

The call coincides with the release of new research revealing strong genetic links between anorexia nervosa and suicide attempts,¹ with suicide implicated in a staggering 20 per cent of anorexia-related deaths.²

According to visiting Professor, global lead Principal investigator and Distinguished Professor of Eating Disorders, Department of Psychiatry, School of Medicine, University of North Carolina, USA, Dr Cynthia Bulik, the Anorexia Nervosa Genetics Initiative (ANGI) aims to identify the genes involved in causing the serious and potentially life-threatening illness, affecting an estimated 21,000 New Zealanders.³

“We’re seeking volunteers to shed light on the genes that predispose people to anorexia nervosa, which we know has a strong, but as yet, unspecified genetic predisposition. 

“Twin studies have shown anorexia nervosa is about 60 per cent heritable,⁴ and our research further reveals shared genetic factors may underpin the co-occurrence of both anorexia nervosa and suicide attempts,”¹ Dr Bulik said.

“Anorexia nervosa is a treacherous biological trap that patients have to fight hard to escape from.

“The illness has the highest death rate of any psychiatric disorder, and deaths are typically due to the effects of starvation or suicide,” said Dr Bulik.

“These alarming statistics warrant further understanding of the genetic influences underpinning this illness.”

The researchers anticipate information that emerges from ANGI will identify the genes that rob individuals of healthy and productive lives, and further explain the illness itself, to accelerate and improve treatment outcomes.

“Findings from our recent study underscore the seriousness of anorexia nervosa, and alert doctors and family members to be vigilant for signs of suicide, and to take comments about suicide or wishes to die very seriously,” Dr Bulik said.

In the Anorexia Nervosa, Major Depression and Suicide Attempts: Shared Genetic Factors study, published this month (March 2016) in the Suicide and Life-threatening Behaviour Journal (The American Society of Suicidology), the impact of independent and overlapping genetic and environmental factors of anorexia nervosa, major depressive disorder and suicide attempts was assessed among 7,000 female twins. Findings revealed the co-occurrence of anorexia nervosa and suicide attempts is largely due to shared genetic factors.¹

New Zealand ANGI study investigator, Clinical Psychologist, Dr Jenny Jordan, University of Otago, Christchurch, says studies have shown a strong genetic link to all three conditions for decades, however scientists have been unable to pinpoint particular genes or determine where the genetic link among and between each lies, to date.

“We are keen for any New Zealander who is living with, or has recovered from anorexia nervosa, to join our very important scientific journey of discovery.

“Greater recognition of the genetic contribution to anorexia nervosa is validating for people living with the desperation and despair associated with anorexia nervosa,” said Dr Jordan.

“We’ve found ANGI participants are passionate about their contribution to improving understanding of anorexia nervosa and reducing the risk to others in the future.”

A total of 180 New Zealanders have been recruited into ANGI to date, with researchers aiming to attract a total of 400 participants country-wide. Researchers will be analysing DNA samples through a process known as ‘genome-wide association’, comparing the DNA of people who have never had an eating disorder to those who currently have, or have had, anorexia nervosa. Comparative analysis not only serves to identify and discover genes that predispose people to eating disorders, but to also pinpoint genes responsible for depression, anxiety, alcoholism and other common mental illnesses.⁵

ANGI is being conducted in four centres worldwide, including a combined New Zealand and Australian site, US, Denmark and Sweden. New Zealand and Australia plan to contribute more than a quarter of the total 13,000 DNA samples required for the initiative.

“To date, 180 New Zealanders have provided us with a blood sample, only three per cent of whom are male. We therefore require another 220 volunteers by July, 2016 to complete our New Zealand contribution to this groundbreaking international research. To do this, we need substantial community support from both men and women,” Dr Jordan said.

ANGI NZ investigator and geneticist, Professor Martin Kennedy, University of Otago, Christchurch, says encouraging people who have, or have had, anorexia nervosa to participate in the initiative will help transform current knowledge of anorexia nervosa causes.    

“ANGI will enable us to work towards a greater understanding of, and ultimately improved treatments for, the illness.

“We know the causes of anorexia nervosa are varied and complex⁶ and include a combination of environmental, social and cultural factors.⁷ However, genetic predisposition is a known cause and should be a key area of focus,” said Dr Kennedy.  

“Given recent technical advances in genomics, we are hoping to identify the specific genes that may be responsible for anorexia nervosa and associated co-occurrences, and thereby pave the way for new treatments that specifically target the illness.”

Anorexia nervosa is characterised by an obsessive desire to lose weight through restricting calorie intake and is associated with low body weight, difficulty maintaining a healthy body weight, fear of weight gain and extreme focus on weight and shape.⁵

The illness afflicts people from all age groups, socio-economic and cultural backgrounds.⁶ While anorexia nervosa typically starts, and is more common among adolescent girls,⁸ affecting four-in-every-100, some of the most serious forms of the illness occur in adults aged 25-to-45 years.⁹ 

Devoted mother-to-three, Lucy, 49, Christchurch, watched anxiously as her beloved adolescent son, Fin, 17, battled the potentially devastating illness for three years. In 2013, the then healthy 14 year old teenager began an exercise and weight loss regime to “fit in” with his peers. However, this new regime soon spiralled out of control, leading to a devastating diagnosis of anorexia nervosa. Several arduous hospitalisations later, Fin is now in recovery.

“Having anorexia nervosa is like being a puppet on a string. You’re the puppet, and the anorexia nervosa is the hand controlling the string. You do whatever it says. It’s like being possessed without knowing that you are,” Fin said.

Today, Fin’s mother runs a support group for parents or carers of loved ones living with an eating disorder.

“It’s not only the person directly affected by anorexia nervosa who is affected by the illness. Some parents and family members of the individual with the illness, lose their friends and struggle with isolation and various other difficulties, to the equivalent of their loved one battling the illness,” said Lucy.

“Social situations can be really tough, as a child living with anorexia nervosa doesn’t behave the same way as other children, and this can be confronting for many people.”

“I urge every New Zealand woman and man aged 14 and above, who has lived with, or is continuing to live with anorexia nervosa, to join the ANGI community and participate in this groundbreaking research to identify genes that play a role in the development of this life-threatening illness,” Fin said.

While full recovery of anorexia nervosa is possible, particularly with early treatment⁶ and the support of a multidisciplinary healthcare team,¹⁰ ANGI NZ scientists hope their research will lead to a better understanding of the illness, enabling a more successful treatment process.

“Participating in ANGI is easy and free. Volunteers simply complete a 10-minute online, confidential survey and roll up their sleeves to provide a very small blood sample,” said Prof Bulik.

“It costs nothing apart from a little time, but could make a genuine contribution to solving this devastating illness.” 

Volunteers can be male or female aged 14 and above (those under 18 require parental or guardian consent) who:

• Currently have anorexia nervosa; or
• Have had anorexia nervosa at some stage in their lives. 

To learn more, or to register for the study:

• Visit http://www.angi.nz
• Email angistudy@otago.ac.nz
• Call ANGI NZ on 03 372 0400.

Blood samples will be used to extract DNA which will be bio-banked for immediate and future genetic analysis under strict confidentiality. This research project has been approved by the Southern Health and Disability Ethics Committee (New Zealand; 14/STH/115).

After completing the online survey, and provided informed consent is witnessed in person or by Skype, participants are required to attend their local pathology clinic armed with an ANGI blood collection kit sent to them by ANGI researchers from the University of Otago, Christchurch.

For more information, or to register for ANGI, head to www.angi.nz. 

If you, or a loved one is currently living with anorexia nervosa, Eating Disorders Association of NZ (EDANZ) offers support via phone (0800 2 EDANZ) and email (info@ed.org.nz).

DIGITAL MEDIA KIT:         Available for download TUES, MARCH 22, fromhttp://www.angi.nz/media/

To join the conversation: Like us on Facebook: @ ANGIstudy.NZ Follow us on Twitter: @ANGI_NZ

References 

1. Thornton LM, Welch E, Munn-Chernoff MA, Lichtenstein P, Bulik CM. Anorexia nervosa, major depression and suicide attempts: Shared genetic factors. Suicide and Life-Threatening Behaviour. Doi: 10.1111/sltb.12235.
2. Arcelus J et al. Mortality rates in patients with anorexia nervosa and other eating disorders: A meta-analysis of 36 studies. Archives of General Psychiatry. 2011; 68:724-731. Doi: 10.1001/archgenpsychiatry.2011.74.
3. Bulik , C. M. (2015). Q & A: Anorexia Nervosa Genetics Initiative (ANGI).   Retrieved from angi.nz
4. Kennedy, M., Jordan, J., Martin, N., Wade, T., Montgomery, G., & Bulik, C. (2015). The Anorexia Nervosa: Genetics Initiative (ANGI): Australia and New Zealand join forces. Journal of Eating Disorders, 3(Suppl 1), P10.
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7. Anorexia Nervosa, National Eating Disorders Collaboration, Australia,nedc.com.au/anorexia-nervosa [last accessed December 22, 2014].
8. Wade T, Bergin J, Tiggerman M, Bulik C & Fairburn C. Prevalence and Long-Term Course of Lifetime Eating Disorders in an Adult Australian Twin Cohort. Australian and New Zealand Journal of Psychiatry. 2006; 40:121-128.
9. Anorexia Nervosa, Department of Health, Australia,health.gov.au/internet/publications/publishing.nsf/Content/mental-pubs-a-anorex-toc~mental-pubs-a-anorex-1 [last accessed December 22, 2014].
10. Anorexia Nervosa, Better Health Channel, Victorian State Government,betterhealth.vic.gov.au/bhcv2/bhcarticles.nsf/pages/Anorexia_nervosa [last accessed December 22, 2014].