NEW YORK ― A single injection of cosmetic botulinum toxin (BTX), which is typically used to improve the appearance of facial wrinkles, may be an effective treatment for depression.
In one of the first studies to suggest this, investigators at the Hannover Medical School in Germany found that treating the facial muscles involved in emotion with botulinum alleviates depressive symptoms.
“Our emotions are expressed by facial muscles, which in turn send feedback signals to the brain to reinforce those emotions. Treating facial muscles with botulinum toxin interrupts this cycle,” study investigator Prof. Tillmann Kruger said at a press conference here at the American Psychiatric Association’s 2014 Annual Meeting.
According to the investigators, positive effects on mood have been observed in patients who have undergone BTX treatment for glabellar frown lines. A previous open case series showed that depression remitted or improved after such treatment.
To confirm these results, Dr. Kruger and colleague M. Axel Wollmer, MD, from the Asklepios Clinic North Ochsenzoll in Hamburg, Germany, conducted a randomized, double-blind, placebo-controlled trial of BTX injection as an adjunctive treatment for major depression.
A total of 30 patients with high levels of chronic and treatment-resistant depression were enrolled in the study. Patients were randomly assigned to receive a single injection of BTX or a single injection of saline placebo.
The study’s primary end point was a change from baseline in depressive symptoms, as measured by the 17-item Hamilton Depression Rating Scale (HAMD17), during the 16-week study.
Six weeks after a single treatment, the BTX group experienced an average 47.1% reduction in HAMD17 scores vs 9.2% in the placebo group.
The investigators found that the effect size was even larger at the end of the study and that treatment-dependent clinical improvement was also reflected in the Beck Depression Inventory and the Clinical Global Impressions Scale.
“This study shows that a single treatment of the glabellar region with botulinum toxin may shortly accomplish a strong and sustained alleviation of depression in patients who did not improve sufﬁciently on previous medication. It supports the concept that the facial musculature not only expresses but also regulates mood states,” the investigators write.
Dr. Kruger said BTX may offer a “novel, effective, well-accepted, and economic therapeutic tool for the treatment of major depression.”
These findings have since been replicated in 2 subsequent studies, one by Michelle Magid, MD, and colleagues, which was presented in March at the American Academy of Dermatology 72nd Annual Meeting and reported by Medscape Medical News at that time, and the other by Eric Finzi, MD, PhD, and colleagues, which was published in the May issue of Journal of Psychiatric Research and was also reported by Medscape Medical News.
Dr. Kruger reported that he and his colleagues are currently conducting a meta-analysis of the 3 randomized trials in an effort to “further corroborate this novel treatment approach.” The researchers are also testing BTX’s therapeutic potential in other psychiatric disorders.
Commenting on the study, press conference moderator Jeffrey Borenstein, MD, president and CEO of the Brain and Behavior Research Foundation in New York City and chair of the American Psychiatric Association’s Council on Communications, said that pursuing new treatments for depression is “crucial.”
Dr. Borenstein added that he would like to see this line of research pursued in studies that include larger numbers of patients.