title: Orthostatic intolerance and gastrointestinal motility in adolescents with nausea and abdominal pain.
abstract: OBJECTIVE
  To describe the relationships between gastric emptying, autonomic function, and postural tachycardia in adolescent patients with nausea and/or abdominal discomfort. It was hypothesized that patients with both gastrointestinal symptoms and symptoms of orthostatic intolerance are more likely to show abnormal tilt table results and delayed gastric emptying.
  
  
  METHODS
  A retrospective review was conducted of adolescent patients who came to a pediatric referral center because of nausea and dyspepsia and who subsequently underwent both autonomic reflex screening and gastric emptying testing. Patients with a heart rate change of 30 or more beats per minute on the heads-up tilt table test were assigned to the postural orthostatic tachycardia syndrome (POTS) group (n = 21), and those with a heart rate change of fewer than 30 beats per minute on the heads-up tilt table test were assigned to the non-POTS group (n = 10).
  
  
  RESULTS
  There was no significant difference between the POTS and non-POTS groups with regard to presenting symptoms (P > 0.05). Overall, 13 (42%) individuals had abnormal gastric emptying results (delayed in 6, accelerated in 7), but gastric emptying scores were similar between the POTS and non-POTS groups. Furthermore, there was no correlation between an individual's gastric emptying results at 1, 2, and 4 hours and that person's heart rate change on HUT (r = -0.05, -0.15, and -0.19).
  
  
  CONCLUSIONS
  Although altered gastric emptying and postural tachycardia are common in a referral population of adolescents with nausea and/or abdominal discomfort, the clinical presentation was not predictive of test results. Furthermore, delayed gastric emptying was not correlated with the current definition of postural tachycardia.
authors: Department of Pediatric & Adolescent Medicine, Division of General Pediatric and Adolescent Medicine Mayo Clinic College of Medicine, Rochester, Minnesota 55905, USA.
authors: Ryan M
authors: RM
authors: Antiel
authors: Justin M
authors: JM
authors: Risma
authors: Rayna M
authors: RM
authors: Grothe
authors: Chad K
authors: CK
authors: Brands
authors: Philip R
authors: PR
authors: Fischer
mesh_terms: D015746:Abdominal Pain / Q000209:etiology; D000293:Adolescent; D016022:Case-Control Studies; D002648:Child; D004244:Dizziness / Q000209:etiology; D005260:Female; D005746:Gastric Emptying / Q000502:physiology*; D005769:Gastrointestinal Motility / Q000502:physiology*; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D009325:Nausea / Q000209:etiology; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D013564:Sympathetic Nervous System / Q000503:physiopathology*; D013610:Tachycardia / Q000503:physiopathology*; D018667:Tilt-Table Test