Biomarkers could spell the end of anorexia nervosa

Tiny, unconscious eye movements are thought to be a biomarker for anorexia nervosa. Photo by Amanda Dalbjörn on Unsplash

What are biomarkers and why are they important?  

Biomarkers are characteristics of our bodies that can be measured. They include things like blood sugar, heart rate and bone density. They help us detect, screen, prevent and treat physical illnesses, but they’re not established for use in clinical practice for any mental illness. That is, until now. 

Revolutionising screening, detection and diagnosis 

Head of the SWAN Research Group, Dr Andrea Phillipou, found that a combination of a type of atypical, twitching eye movement, called ‘square wave jerks’, together with anxiety, is a promising two-element biomarker for anorexia nervosa. 

Square wave jerks were observed in people currently with anorexia nervosa, people who had recovered, and sisters of people with anorexia nervosa. The finding in sisters is critical, because it reveals there is likely a genetic, inherited link. 

New and more effective treatments 

Biomarkers also tell us about the underlying biological mechanisms involved in an illness. 

‘Eye movements use very specific brain regions, so when we see these types of atypical eye movements, we have a pretty good idea about which brain areas are not working the way they should,’ says Dr Phillipou. 

‘These areas are also involved in other functions related to anorexia nervosa – such as body image – so it gives us an idea of which brain areas we could target with treatments such as non-invasive brain stimulation.’ 

Prevention over cure 

Biomarkers are present regardless of illness state. Think of it as genetic determinism: your body is genetically pre-programmed for various outcomes – some better than others. 

‘With more research, we’re hoping that we’ll be able to use this biomarker as a screening tool to identify people who may be at risk of developing anorexia nervosa,’ says Dr Phillipou. 

‘If we’re able to do this, we’ll be able to implement things to help prevent people developing the condition in the first place.’ 

It’s a discovery that has the power to rewrite someone’s life story.

This research was carried out by researchers at Swinburne, Deakin, Monash Alfred Psychiatry Research Centre (MAPrc) and University of Toronto.