Researchers tracked about 330 children with abdominal pain that had no specific cause, a condition called functional abdominal pain syndrome (FAPS), and compared them with 150 children without stomach aches.
Psychiatric evaluations conducted nine years later, on average, showed the risk of anxiety disorders was about four to five times higher for people who had abdominal pain as kids.
About 50 percent of people who had FAPS as kids had social anxiety, phobias or other anxiety disorders while growing up or in adulthood, compared with about 20 percent of people who didn't have the condition.
The findings suggest that anxiety should be an important consideration when treating children who get stomachaches, the researchers said.
"It's not just that they are anxious because of the pain. We saw that once the abdominal pain went away, they still had clinically significant anxiety," said study researcher Lynn Walker, professor of pediatrics at Vanderbilt University in Nashville, Tenn.
"We need to address the pain and anxiety together, and help kids cope better with their discomfort," Walker said.
Abdominal pain is common in children, but some children who are otherwise healthy get "medically unexplained" stomachaches, sometimes several times a day. The pain usually goes away as children grow, but meanwhile, it can interfere with their normal lives, making it difficult to attend school or play with other kids.
"The children might be more likely to stay home, get behind school work and be no longer connected with their friends, which over time may create a lot of stress for them," Walker said. [11 Signs of Mental Illness in Children ]
The unexplained stomachaches can be source of stress for parents too, who may become too protective, making the child even more worried that something may be wrong.
"Once the physician has done the proper evaluation, and says there's really nothing seriously wrong here, then the parents should start behaving more like a coach, and encourage the children to continue their activities, instead of keeping them at home."
It is not known what causes FAPS, but it is thought that the nervous system might have a role.
"It's not that the pain is not real," Walker said, but it might be that the brain doesn't properly respond to the sensations coming from the gut.
"We have a natural ability to turn down the pain signal once whatever's wrong has healed, or if there's nothing wrong. People who are anxious have more difficulty turning off the alarm system," she said.
The findings also suggest that children with abdominal pain have an increased risk of depression in adulthood. In the study, 40 percent of adults who had abdominal pain as children had depression during their lifetime, compared with 16 percent of adults in the control group.
Study participants started having both anxiety and abdominal pain early in childhood, and the researchers could not identify which condition occurred first. It may be that some children are genetically predisposed to both anxiety and hypersensitivity to pain, they said.
It is also possible that in some children, stomachaches causes stress, which in turn makes them more vigilant and attentive to minor discomforts, therefore feeding into a vicious cycle, Walker said.
"We think that chronic pain is better treated in a multidisciplinary fashion, in which you not only have to look for a disease, but you also look at emotional and psychological aspects of it, and address all of those together in an integrated fashion," she said.
The study was published Monday, Aug. 12, in the journal Pediatrics.
- 9 Weird Ways Kids Can Get Hurt
- 5 Controversial Mental Health Treatments
- 10 Ways to Promote Kids' Healthy Eating Habits