Anxiety disorders linked to fear of the unknown

By Barry Eitel

SAN FRANCISCO

Psychologists funded by the National Institutes of Health (NIH) announced Friday that an overarching fear of the unknown might link a range of anxiety disorders and could change how doctors treat mental illness.

Researchers working out of the University of Illinois at Chicago announced they have discovered that many psychological issues including panic disorder, social anxiety disorder and a slew of phobias share an underlying trait: increased sensitivity to an unspecified threat.

This discovery could steer treatment of some disorders away from focusing on specific diagnoses and toward treating the common characteristic.

The study published Friday in the Journal of Abnormal Psychology received federal funding via the National Institute of Mental Health.

"We may, one day, open up clinics that focus on treating the underlying common neurobiology of the patient's symptoms instead of individual diagnoses,” Stephanie Gorka, a corresponding author on the study, said in a statement. “A treatment, or set of treatments, focused on sensitivity to uncertain threat could result in a more impactful and efficient way of treating a variety of anxiety disorders and symptoms."

According to anxiety disorder sufferers, the unspecified threat was defined by the unpredictability of its timing, intensity or duration. The fear a threat caused was marked by extreme vigilance and a general feeling of apprehension. In comparison, a specific threat ignites a “fight or flight” response, like a hungry dog charging someone.

The study was conducted on 150 participants, where more than half was diagnosed with a specific anxiety disorder. Among other tests, researchers gave each participant a series of mild electric shocks of varying predictability. They found that those suffering from anxiety disorders reacted much more strongly to the unpredictable shocks.

"We classify so many different mood and anxiety disorders, and each has its own set of guidelines for treatment, but if we spend time treating their shared characteristics, we might make better progress," senior author Dr. K. Luan Phan said in a statement. "Knowing that sensitivity to uncertain threat underlies all of the fear-based anxiety disorders also suggests that drugs that help specifically target this sensitivity could be used or developed to treat these disorders."

Anxiety disorders are the most common types of mental illness. A 2012 study covering 91 countries found 7.3 percent of people worldwide suffer from anxiety. The NIH believes 18 percent of the United States population suffers from the condition.