Multisite Pain Is Highly Prevalent in Children with Functional Abdominal Pain Disorders and Is Associated with Increased Morbidity.

OBJECTIVES: To characterize the types of multisite pain experienced by children with functional abdominal pain disorders (FAPDs) and to examine differences in psychosocial distress, functional disability, and health-related quality of life in children with multisite pain vs abdominal pain alone. STUDY DESIGN: Cross-sectional study of children ages 7-17 years (n = 406) with pediatric Rome III FAPDs recruited from both primary and tertiary care between January 2009 and June 2018. Subjects completed 14-day pain and stool diaries, as well as validated questionnaires assessing abdominal and nonabdominal pain symptoms, anxiety, depression, functional disability, and health-related quality of life. RESULTS: In total, 295 (73%) children endorsed at least 1 co-occurring nonabdominal pain, thus, were categorized as having multisite pain with the following symptoms: 172 (42%) headaches, 143 (35%) chest pain, 134 (33%) muscle soreness, 110 (27%) back pain, 94 (23%) joint pain, and 87 (21%) extremity (arms and legs) pain. In addition, 200 children (49%) endorsed 2 or more nonabdominal pain symptoms. Participants with (vs without) multisite pain had significantly higher abdominal pain frequency (P < .001) and severity (P = .03), anxiety (P < .001), and depression (P < .001). Similarly, children with multisite pain (vs without) had significantly worse functional disability (P < .001) and health-related quality of life scores (P < .001). Increasing number of multisite pain sites (P < .001) was associated with increased functional disability when controlling for demographic and other clinical factors. CONCLUSIONS: In children with FAPDs, nonabdominal multisite pain is highly prevalent and is associated with increased psychosocial distress, abdominal pain frequency and severity, functional disability, and lower health-related quality of life.