Anorexia is an eating disorder that makes people lose more weight than what is considered healthy. According to the The National Association of Anorexia Nervosa and Associated Disorders (ANAD), eating disorders have the highest mortality rate of all mental health disorders.
Eating disorders affect 24 million adults in the United States and approximately 70 million people worldwide. The vast majority of these individuals are female, with 90 percent of people with eating disorders being women aged between 12 and 25.
Anorexia affects little under 1 percent of the entire female population in the U.S. The disorder can lead to serious health issues over time because of malnutrition, such as the weakening of bones and the immune system, heart problems because of the lack of potassium in the blood, as well as overall insufficient levels of proteins, vitamins, and nutrients.
Additionally, anorexia is often accompanied by other mental health issues, such as depression, and puts those affected at a risk of suicide. Of all anorexia-related deaths, 1 in 5 are by suicide.
There are various treatment options available for anorexia, including cognitive behavioral therapy and dietary interventions.
New research suggests there is a another safe and effective way of treating this mental health problem.
Assessing the effect of DBS on anorexia symptoms
Canadian researchers have tested the effect of a surgical technique called deep brain stimulation (DBS) on the mood, weight, and overall well-being of 16 patients.
The results of the trial were published in the journal The Lancet Psychiatry.
The researchers - led by Dr. Nir Lipsman from the Sunnybrook Health Sciences Centre in Canada - examined 16 women with ages between 21 and 57 who had lived with anorexia for an average of 18 years. These women had a body mass index (BMI) of 13.8, making them severely underweight.
The women chose to participate in the study because they had tried other treatments with no success, and they were at risk of dying prematurely because of the disorder.
Dr. Lipsman and colleagues surgically implanted electrodes in the subcallosal cingulate area of the patients' brain. This brain region has been shown to display changes in serotonin binding in patients with anorexia. After implantation, the electrodes were used to stimulate the area every 90 microseconds for 1 year. The voltage used was between 5 and 6.5 volts.
The researchers used PET scans to evaluate the brain activity of the patients after undergoing 1 year of DBS.
DBS improved depression symptoms in 10 out of 14 patients
Overall, there were few adverse effects to the treatment. Some of these negative effects were attributable to the anorexia-induced, poor overall health of the patients; one patient had an infection at the site of the electrodes, and five patients had persisting pain after surgery.
One patient had a seizure several months after the electrodes were implanted. The seizure is yet to be explained.
At the end of the trial, there were 14 participants left for follow-up. Mood and anxiety improved for five of these 14 patients, and depression symptoms decreased for 10 of them. The participants' quality of life also improved, according to their own testimony.
The technique also seemed to have a positive effect on the weight of the participants. After 3 months, the first signs of weight improvement began to show, and by the end of the study, the average BMI of the group increased by 3.5 points. Additionally, six of the participants reached a normal BMI, defined as 18.5 or more.
Brain scans also confirmed the benefits of the treatment. After a year of DBS, the participants' brain revealed changes in the regions linked to anorexia. The researchers noted increased activity in the peripheral cortical areas - associated with social perception and social behavior - as well as decreased activity in the putamen, thalamus, and cerebellum.
DBS can be an effective treatment for anorexia
"Anorexia remains the psychiatric disorder with the highest mortality rate, and there is an urgent need to develop safe, effective, evidence-driven treatments that are informed by a growing understanding of brain circuitry," says study author Prof. Andres Lozano, from the University of Toronto in Canada.
"While our results show some early promise, more research will be needed before this becomes available for patients with anorexia," he continues. "Our findings emphasize the need for continued research into novel neuromodulation strategies for anorexia nervosa, and for psychiatric disorders more broadly."
The study's lead author also comments on the significance of the findings. "Our study suggests that a focal brain intervention, deep brain stimulation, may have an impact on the circuitry of symptoms that serve to maintain anorexia and make it so difficult to treat," Dr. Lipsman says.
Dr. Carrie McAdams, from the University of Texas, weighs in on the findings in a linked commentary.
"Nearly half of adult women with anorexia nervosa relapse within a year [of receiving intensive conventional treatment]. This work shows how modern neuroscience can lead to a new treatment and simultaneously improve understanding of perpetuating factors in a complex, multifactorial disease.
Both mood and social function warrant further examination as potential neural factors that might perpetuate anorexia nervosa in adults. Difficulty in changing these factors, which are not part of the diagnostic symptoms of anorexia nervosa, could contribute to the poor outcomes seen with conventional treatments."
Dr. Carrie McAdams
Some of the limitations of the study include the small number of the participants, as well as the absence of a control group, which could suggest the positive effects are attributable to a placebo effect. However, the authors say this is unlikely, since the results persisted for a year and PET scans confirmed the positive changes in brain activity.