title: Impaired conditioned pain modulation in youth with functional abdominal pain.
abstract: Functional abdominal pain (FAP) is associated with enhanced pain responsiveness. Although impaired conditioned pain modulation (CPM) characterizes adults with a variety of chronic pain conditions, relatively little is known about CPM in youth with FAP. This study assessed CPM to evoked thermal pain in 140 youth (ages 10-17), 63 of whom had FAP and 77 of whom were healthy controls. Multilevel models demonstrated weaker CPM effects in youth with FAP than in healthy youth, as evident in slower within-person decreases in pain ratings during the conditioning phase. Weaker CPM effects were associated with greater somatic symptom severity and functional disability. Pain responses in youth with FAP were heterogeneous, with 43% of youth showing an unexpected increase in pain ratings during the conditioning phase, suggesting sensitization rather than CPM-related pain inhibition. These findings highlight directions for future research on the emergence and maintenance of FAP in youth.
authors.affiliation: Department of Family and Community Medicine, Meharry Medical College, Nashville, TN, USA.|Center for Molecular and Behavioral Neuroscience, Meharry Medical College, Nashville, TN, USA.|Department of Psychology, Vanderbilt University, Nashville, TN, USA.
authors.forename: Matthew C
authors.initials: MC
authors.lastname: Morris
authors.affiliation: Department of Pediatrics, Vanderbilt University School of Medicine, Nashville, TN, USA.|Vanderbilt Kennedy Center, Nashville, TN, USA.
authors.forename: Lynn S
authors.initials: LS
authors.lastname: Walker
authors.affiliation: Vanderbilt Kennedy Center, Nashville, TN, USA.|Department of Anesthesiology, Vanderbilt University School of Medicine, Nashville, TN, USA.
authors.forename: Stephen
authors.initials: S
authors.lastname: Bruehl
authors.affiliation: Department of Psychology and Human Development, Vanderbilt University, Nashville, TN, USA.
authors.forename: Amanda L
authors.initials: AL
authors.lastname: Stone
authors.affiliation: Department of Family and Community Medicine, Meharry Medical College, Nashville, TN, USA.
authors.forename: Alyssa S
authors.initials: AS
authors.lastname: Mielock
authors.affiliation: Department of Pediatrics, Vanderbilt University School of Medicine, Nashville, TN, USA.|Vanderbilt Kennedy Center, Nashville, TN, USA.|Center for Behavioral Health Research, University of Tennessee, Knoxville, TN, USA.
authors.forename: Uma
authors.initials: U
authors.lastname: Rao
mesh_terms: D015746:Abdominal Pain / Q000503:physiopathology*; D000293:Adolescent; D002648:Child; D003213:Conditioning, Psychological / Q000502:physiology*; D004244:Dizziness / Q000209:etiology; D005260:Female; D006261:Headache / Q000209:etiology; D006801:Humans; D006930:Hyperalgesia / Q000503:physiopathology*; D008297:Male; D009325:Nausea / Q000209:etiology; D010147:Pain Measurement; D017288:Pain Threshold / Q000502:physiology*