Autonomic Vagal Nerve Dysfunction in Patients with Ulcerative Colitis

Autonomic nerve function was evaluated in 40 patients with total ulcerative colitis and in 25 patients with irritable bowel syndrome by three established non-invasive tests based on the heart reactions to deep breathing (E/I ratio) and tilt (acceleration and brake index). None of the patients were diabetic. Most of the patients with ulcerative colitis were clinically and biochemically inactive; 10 had previously undergone colectomy. The results were compared with a control group consisting of 56 healthy individuals and 33 previously investigated patients with Crohn's disease, 45% of whom demonstrated autonomic neuropathy (AN). Patients with ulcerative colitis had a significantly lower E/I ratio than controls in age-corrected values, indicating vagal nerve dysfunction. Altogether, 35% had signs of AN. In patients with irritable bowel syndrome 36% had evidence of AN, a figure in agreement with observations from other investigators. We conclude that AN is common in patients with ulcerative colitis, regardless of disease activity and previous colectomy. In contrast to a predominantly sympathetic dysfunction in Crohn's disease, AN in ulcerative colitis was vagal.