Anxiety is estimated to affect one in five U.S. children. But only about half of children and teens who receive treatment actually achieve long-term relief, according to a new study by researchers from the Johns Hopkins University School of Medicine and five other institutions, published in the journal JAMA Psychiatry.

The study, believed to be the first of its kind, followed 288 patients ages 11 to 26 for six years after they were diagnosed with and treated for anxiety. Researchers said the results show how important it is for doctors and therapists to follow up with patients, even after they have received treatment for their anxiety and appear to be recovering.

"Just because a child responds well to treatment early on, doesn't mean our work is done and we can lower our guard," said lead investigator Golda Ginsburg, Ph.D., in a press release.

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Anxiety Among U.S. Children, Teens, and Young Adults

Anxiety disorders are the most common mental illness in the U.S. and affect about 40 million U.S. adults 18 and older, according to the Anxiety and Depression Association of America (ADAA).

About 8 percent of teens ages 13 to 18 are also affected, “with symptoms commonly emerging around age 6,” according to the National Institute of Mental health (NIMH), which estimates that about 25 percent of these children will experience anxiety into adulthood.

While it’s normal for a child to experience symptoms of anxiety, such as nervousness or fear when facing something new or challenging, a child with a chronic anxiety disorder will experience these feelings more intensely, for longer periods of time, and in familiar, everyday situations.

A child with an anxiety disorder may experience a number of conditions that sometimes overlap, including generalized anxiety disorder, obsessive compulsive disorder, separation anxiety disorder, social anxiety disorder, or other specific phobias, according to ADAA.

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Is Anxiety On the Rise?

There appears to be an upswing in the diagnosis of anxiety among kids and young adults. For example, a 2000 study published in the Journal of Personality and Social Psychology, reported that the average American child in the 1980s experienced more anxiety than child patients in the 1950s.

And research from the Nuffield Foundation’s Changing Adolescence Programme states that “the proportion of 15- and 16-year-olds reporting frequently feeling anxious or depressed has doubled in the last 30 years, from one in 30 to two in 30 for boys and one in 10 to two in 10 for girls.”

However, Ginsburg said the rise in the diagnosis of anxiety disorders is hard to judge. 

“(Anxiety disorders among children) have gone up but it’s not clear whether the real prevalence has gone up, or whether we’re just better at identifying and diagnosing the disorder,” Ginsburg said in an interview with Healthline.

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Current Treatment Options

The two most common treatments for children with anxiety are prescription medications and cognitive-behavioral therapy (CBT). A combination of the two has been shown to be more effective, according to ADAA.

During CBT, a therapist teaches the child how to cope with the symptoms of anxiety and develop positive thinking strategies.

In the Johns Hopkins study, participants were treated with medication, CBT, or both. Six years after treatment, 47 percent of the 288 subjects were symptom free, while 70 percent needed further therapy in the years following the initial treatment.

Researchers also found that girls were twice as likely to suffer from anxiety after the initial treatment than boys, which may be due to hormonal and environmental differences, they said.

“Those who were effectively treated, and who responded to the treatment initially were more likely to be healthy at the follow-up,” Ginsburg noted. “That said, the other half relapsed and had anxiety at the follow-up so we need to do a better job at helping those kids.”

Ginsburg said that she hopes her study will lead to better treatment strategies to help prevent relapse.

“I think we should increase our monitoring of kids,” she said. “But I don’t think we know what those strategies are yet to prevent relapse.”

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What Can Parents Do?

According to the study authors, anxiety is caused by a combination of genes along with the environment in which a child is raised. Along with gender, researchers found that family dynamics played a significant role in the risk of long-term anxiety.

“In the context of this study, we did find that kids who came from a family that had more positive interactions and clear rules... were more likely to be in remission at the follow-up,” Ginsburg said. Parents can do their part by making sure to create a positive and supportive environment for their child.

Children of adults with an anxiety disorder are seven times more likely to develop the disorder themselves, according to a 2009 study by researchers at Johns Hopkins. The study found that as few as eight weekly family sessions of CBT reduced symptoms and minimized the chance that the child would develop anxiety later in life.

“Anxiety is considered a gateway disorder because kids who have these illnesses are more likely to have adult psychiatric problems like depression,” Ginsburg said. “So it’s important to follow these kids over time to see if effective treatment prevented the onset of these disorders as well.”

In order to prevent a relapse, parents should continue to be vigilant with respect to monitoring anxiety symptoms, Ginsburg said.

Tell-tale signs that a child is experiencing chronic anxiety include avoiding certain situations, feeling anxious, thinking about worst case scenarios, and focusing on the negative, Ginsburg said.

“If these symptoms begin to emerge again after they are treated, parents should get back in touch with their provider for a check-up,” she said.  

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