Across the United States, 40 million adults suffer from anxiety disorders. They affect 18 percent of the population and are considered the most common mental illnesses in the US. Little is known about the causes. Chronic anxiety comes at a high cost—totaling more than $42 billion in treatment each year. And now researchers are finding the costs could go even deeper.

As Reddit user the_phet shared in Reddit’s science community, a new study out of the Brain Mind Institute, at École Polytechnique Fédérale de Lausanne (EPFL) in Switzerland, shows that chronic anxiety might lead to lower social status—and even trap sufferers there indefinitely.

Researchers used rats to identify how trait-anxiety (a term that refers to levels of stress inherent in personality) affects competitiveness.

Through a series of tests, the scientists assessed each rat’s proclivity for anxiety and labeled them high, intermediate, or low. They then matched high-anxiety rats with low-anxiety ones, of similar age, weight, and size, and put them in competitive situations.

The rats with high levels of anxiety became willingly subordinate when faced with confident peer, and less motivated to compete. The same results occurred across several repeated encounters and, as a result of these interactions, the high-anxiety rats lost ground in the social hierarchy.

Seeking to better understand the brain chemistry behind their results, the scientists studied the rats’ brains. Assessing the mitochondria in the nucleus accumbens, a part of the brain that controls responses to rewards and depression, they found key differences between the high and low-anxiety rats.

The anxious rats showed signs of low mitochondrial functioning and respiration—the process through which cells create energy—and their social ranking fell alongside their mitochondrial functioning.

To ensure the relationship was causal, they manipulated the rats, giving anxious ones a brain boost with a form of Vitamin B3 and the low-anxiety ones an inhibitor. As predicted, the social ranking switched—at least, until the drugs wore off.

The study is the first to connect how brain chemistry affects social hierarchy. Now the scientists are saying their work could lead to the development of pharmaceutical products that could help social anxiety sufferers boost their social status.

Researcher Carmen Sandi says there’s still more work to be done as there are several complicated mechanisms that impact social behavior, but she believes their findings are an important step toward developing better treatments.

“Social interactions are immensely complex,” she explains in a statement. “However, this is an exciting finding that shows a brain mechanism whereby anxious personality affects social competitiveness—and this points to very promising directions in this field.”