A team of researchers from UCLA Health and the Laureate Institute for Brain Research (LIBR) has found a never-before-seen link between the heart and the brain in women with generalized anxiety disorder (GAD), potentially opening a new pathway to treatment.
Nearly seven million adults in the U.S. have GAD – defined as feeling nervous, experiencing gastrointestinal issues, or having a sense of doom over a period of at least six months – according to the Anxiety and Depression Association of America. While it’s established that GAD in women manifests through muscle tension, a rapid heart rate, or shortness of breath, the brain activity associated with these symptoms is unknown.
In a new study, published in JAMA Psychiatry, Olujimi Ajijola, MD, PhD, associate professor of medicine at the UCLA Cardiac Arrhythmia Center, and other researchers used isoproterenol, an adrenaline-like drug normally used to accelerate the heart, to monitor participants’ physical response to fast heart rates, and measured brain activity associated with it using functional magnetic resonance imaging (fMRI). “What we’re trying to probe is: Does the ability to sense one’s internal organs, for example, heart rate, and the intensity of these sensations differ between individuals with elevated anxiety and individuals without anxiety?” Ajijola said.
In the study, 58 women – 29 with GAD and 29 without GAD – were given isoproterenol or saline by injection while their brain was scanned for changes. The researchers found that when women with GAD were given a low dose of isoproterenol, they had a higher heart rate, higher self-reported anxiety, and reduced brain activity in the ventromedial prefrontal cortex, a part of the brain controlling decision making, emotional processing, and self-perception, compared to those without GAD. This abnormal heart-brain link suggests that GAD impacts the brain’s ability to control the body’s reaction to stress and may explain why anxiety can be sparked by seemingly non-threatening triggers.
Currently, treatments for GAD consist of psychotherapy, antidepressants, or exercise. But Ajijola says this new research makes the ventromedial prefrontal cortex a target for new treatments. That region of the brain can undergo stimulation using non-invasive approaches, for example. Overall, this finding “furthers our understanding of the kind of brain-body interactions that are dysfunctional in the setting of generalized anxiety disorder,” Ajijola said.
The other authors on the study were senior author Sahib Khalsa, MD, PhD, and first author Adam Teed, PhD from LIBR, and included others from LIBR as well as The University of Oklahoma and the University of California at San Diego.
Article: Association of Generalized Anxiety Disorder With Autonomic Hypersensitivity and Blunted Ventromedial Prefrontal Cortex Activity During Peripheral Adrenergic Stimulation. JAMA Psychiatry 2022.
Source UCLA Health