Dec. 24, 2008 -- Caitlin Carey, 17, says her bouts with anxiety began when she was 6 and were not just a matter of being "a nervous Nelly."
Over time, she started washing her hands excessively to rid herself of germs. Then she worried about sinning and prayed constantly. Next, she feared being imperfect, and suffered from panic attacks two or three times a day. Writing a term paper in the 10th grade, the Bridgewater, N.J., student became too anxious and overwhelmed by its flaws to go on. She didn't sleep or eat for three days.
"You are just repeating stuff over and over in your head and the fear just keeps coming back," Caitlin told ABC News Wednesday. "It is very difficult to perform your daily functions, to go to school, and go to your activities and interact with people when your fear is always in the back of your mind."
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Now, Caitlin hasn't had a panic attack in two years. She has been on five different kinds of medication and sees a therapist to cope with her anxiety and her obsessive-compulsive disorders. She is pleased with the results.
"Since I've had medication it has helped so much, and since I have had treatment," she said. "But anxiety is very rough because it is always in the back of your mind and sometimes it creeps into the forefront of your mind. You are always afraid of something."
Caitlin is not the only one. Childhood anxieties are incredibly prevalent, and at times far more severe than the monster under the bed. Overwhelming and debilitating anxieties affect an estimated 10 to 20 percent of children, according to the American Academy of Child and Adolescent Psychiatry. Even at the low end of that range, the upshot is that more children may suffer from severe anxiety than with attention-deficit hyperactivity disorder, or ADHD.
But how to best treat those children is a difficult question, and little has been published about how well therapy and medication work together.
A study unveiled today that will be published in the New England Journal of Medicine aims to provide answers. It finds that the combination of cognitive behavioral therapy and the medication sertraline, known as Zoloft, was more effective than either method on its own, and fared far better than giving kids a placebo.
"Both cognitive behavioral therapy and sertraline reduced the severity of anxiety in children with anxiety disorders," the report concluded. "A combination of the two therapies had a superior response rate."
To assess nearly 500 kids battling separation, social and generalized anxiety disorders, researchers randomly gave them different treatments -- whether medication, cognitive behavioral therapy or a combination of the two. A fourth group received a placebo.
In turn, results showed that 81 percent of kids who received both therapy and medication saw marked improvements in overcoming their anxiety. Of those who received behavioral therapy alone, 61 percent responded to treatment, versus 56 percent who saw changes with medication alone. Of those kids given a placebo, 26 percent of them saw improvements.
"We have three good treatments that worked very, very well," said Dr. John Walkup, study author and pediatric psychiatrist at Johns Hopkins Children's Center in Baltimore, Md. "So if people have the time and the resources and the availability they ought to do combination treatment."
Whether separation anxiety, fear of social situations, worries about dying or panic disorder, doctors see the same anxiety disorders in children that they do in adults.
But those kids often fly under the radar.
"Kids who have attention deficit hyperactivity disorder, they are disruptive in the classroom, teachers notice it, families notice it, everybody notices it," Walkup said. "Anxiety kids are quiet, they are the ones who people miss, they kind of fall between the cracks, if you will, because they are anxious, they are avoidant."
To cope, cognitive behavioral treatment teaches patients new methods to change their behaviors. For instance, in hour-long therapy sessions given throughout the study, kids received training on handling their anxieties and practiced how they would respond to anxiety-provoking situations.
"The toolkit is going to contain a variety of self-soothing techniques that the child can use in those moments where fear or worry is getting the best of them," said clinical psychologist Penny Donnenfeld.
The study found that especially when combined with the medication sertraline, which works by helping nerve cells send the chemical serotonin in the brain, doctors saw results.
Although not part of the study, which examined kids between 7 and 17, Caitlin said her own experiences mirror its results.
"I think that a combination of therapy and medications work best for me and works best for most people," Caitlin said.
"There are people out there suffering mentally, not just physically, that need help and need treatment, and that treatment can really give you your life back," she said.
Caitlin has also launched a Web site, www.stepoutofthesilence.org, to encourage other young people to speak up about their struggles, the kind of effort that her mother, Tina Carey, is thrilled to see.
"Within two or three months, Caitlin, all of a sudden, the thing that I could see most was I could see joy in her face and I could see choice," she said. "And those two things were not evident before that."
Walkup said he hopes treating childhood anxieties will help prevent problems later in life.
The ideal is that "they won't have the same kinds of problems that kids who are untreated have: risk for depression, risk for anxiety as they move into adolescent years, and substance abuse problems," Walkup said.