Children who experience functional abdominal pain are at increased risk of anxiety that persists into early adulthood, findings from a prospective case-control study suggest.
The lifetime risk of an anxiety disorder in 332 patients who were diagnosed with functional abdominal pain (FAP) during childhood was 51.2%, compared with 20.4% in 147 control subjects. After controlling for age and gender, those who experienced FAP in childhood had a nearly fivefold increased lifetime anxiety disorder risk (odds ratio, 4.59), Grace D. Shelby, Ph.D., of Vanderbilt University, Nashville, Tenn., and her colleagues reported online Aug. 12 in Pediatrics.
"Similarly, a significantly higher proportion of the FAP group met criteria for [one or more] current anxiety disorders at follow-up, compared with the control group (30.4% vs. 11.6%). The odds ratio for any current anxiety disorder was 3.57 times greater for FAP, compared with controls," the investigators said (Pediatrics 2013 Aug. 12[doi:10.1542/peds.2012-2191]).
The most common anxiety disorder in the FAP group was social anxiety disorder, which was diagnosed in 25.9% of the patients, whose lifetime risk of social anxiety was nearly six times greater than the risk among controls (OR, 5.84) and whose risk for current social anxiety disorder at follow-up was more than eight times greater than the risk among controls (OR, 8.14), they said.
Patients with functional abdominal pain also were at increased lifetime risk of depressive disorders, compared with controls (40.1% vs. 16.3%; OR, 2.62), although current depression risk was low and did not differ between the groups.
The risk of both anxiety disorders and depressive disorders was greatest among those with FAP who met Rome III Diagnostic Questionnaire for Functional Gastrointestinal Disorders criteria for an abdominal pain-related functional gastrointestinal disorder (FGID) at follow-up.
In most study participants who met criteria for a lifetime anxiety disorder, onset occurred during childhood and the age of onset did not differ between the cases and controls (mean age of onset, 7.78 years and 8.97 years, respectively). Conversely, the onset of depressive disorders was usually during adolescence; the mean age of onset for depression also did not differ between cases and controls (mean of 15.96 and 14.92 years, respectively).
Most FAP patients with a lifetime anxiety disorder (72.62%) reported onset before their FAP evaluation, and most of those with lifetime depressive disorders (77.27%) reported onset after their FAP evaluation, the investigators said.
Patients in this study were consecutive new patients, aged 8-17 years, who were evaluated between 1993 and 2007 at the Vanderbilt pediatric gastroenterology service for abdominal pain lasting 3 or more months. Control subjects were children without abdominal pain who were recruited from area schools and who participated in a health survey in the same time period. Those who had reached at least age 12 years, and who were initially evaluated at least 4 years prior, were included in the follow-up study and were followed prospectively for a mean of 8.49 years; subjects were re-evaluated at a mean age of 20.01 years.
The findings support those of a smaller study published in 2001 (Pediatrics 2001;108:e1) that also showed a link between recurrent abdominal pain in childhood and increased likelihood of meeting diagnostic criteria for lifetime and current anxiety disorders in adulthood. The current findings "underscore the importance of a biopsychosocial approach to FAP that includes screening for anxiety and depression," the investigators said, adding that future research should assess whether interventions for mental health conditions in FAP also improve abdominal pain outcomes.
This study was supported by grants from the National Institute on Child Health and Development, Vanderbilt Kennedy Center, Vanderbilt Digestive Disease Research Center, and the Vanderbilt Clinical and Translational Science Award from the National Institutes of Health. Dr. Shelby was supported by a training grant from the National Institute of Mental Health. The authors reported having no other disclosures.