title: Autonomic Dysfunction Correlates with Clinical and Inflammatory Activity in Patients with Crohn's Disease.
abstract: BACKGROUND
  Autonomic dysfunction has been implicated in Crohn's disease (CD). We aimed to investigate heart rate variability (HRV) as a marker of possible autonomic imbalance in patients with CD.
  
  
  METHODS
  Thirty patients with CD and 30 age- and gender-matched healthy controls were enrolled in a prospective cohort study and underwent HRV study. Anxiety level was scored using the STAI questionnaire and CD clinical activity was assessed by Harvey-Bradshaw index. Blood tests including inflammatory markers were obtained for all participants.
  
  
  RESULTS
  CD subjects had lower mean blood pressure (85.51 ± 11.07 mm Hg, 91.51 ± 6.99, P = 0.015) and albumin and significantly higher CRP and IL-6 compared with controls (P < 0.002 for all comparisons). Mean HRV values of very low-frequency power and low-frequency power components were significantly lower among CD subjects (P = 0.038 and 0.027, respectively), implying a predominant sympathetic tone. Anxiety level scores were significantly higher among patients with CD for both state anxiety (P = 0.001) and trait anxiety (P < 0.0001). However, patients with active disease had similar anxiety scores as patients in remission, yet had a significantly lower BMI, lower albumin level, and higher CRP and IL-6 levels (P < 0.05 for all comparisons). Moreover, despite similar anxiety scores, patients with active disease had higher pulse rate (P = 0.02) and lower HRV indexes, which correlated with albumin levels(r = 0.7, P = 0.001).
  
  
  CONCLUSIONS
  Although patients with CD have higher anxiety levels compared with controls, they exhibit depressed HRV independent of this anxiety state and in direct correlation with disease activity and inflammatory markers. These observations suggest an inherent imbalance of autonomic function associated with active inflammation.
authors.affiliation: Departments of *Gastroenterology; and †Internal Medicine E, Sheba Medical Center, Sackler School of Medicine, Tel-Aviv University, Tel-Aviv, Israel.
authors.forename: Tal
authors.initials: T
authors.lastname: Engel
authors.forename: Shomron
authors.initials: S
authors.lastname: Ben-Horin
authors.forename: Marc
authors.initials: M
authors.lastname: Beer-Gabel
mesh_terms: D000328:Adult; D001007:Anxiety / Q000523:psychology; D001342:Autonomic Nervous System Diseases / Q000097:blood / Q000503:physiopathology*; D015415:Biomarkers / Q000097:blood*; D001794:Blood Pressure; D015992:Body Mass Index; D002097:C-Reactive Protein / Q000032:analysis; D016022:Case-Control Studies; D003424:Crohn Disease / Q000097:blood / Q000503:physiopathology* / Q000523:psychology; D005260:Female; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D018836:Inflammation Mediators / Q000097:blood*; D015850:Interleukin-6 / Q000097:blood; D008297:Male; D011446:Prospective Studies; D012074:Remission Induction; D012709:Serum Albumin / Q000032:analysis; D011795:Surveys and Questionnaires
chemical_list: D015415:Biomarkers; C508600:IL6 protein, human; D018836:Inflammation Mediators; D015850:Interleukin-6; D012709:Serum Albumin; D002097:C-Reactive Protein