Sympathetic nerve dysfunction is common in patients with chronic intestinal pseudo-obstruction

To clarify whether disturbances in the autonomic nervous system, reflected in abnormal cardiovascular reflexes, could explain symptoms of impaired heat regulation in patients with intestinal pseudo-obstruction.

Chronic intestinal pseudo-obstruction is a clinical syndrome characterized by diffuse, unspecific gastrointestinal symptoms due to damage to the enteric nervous system or the smooth muscle cells. These patients often complain of excessive sweating or feeling cold, suggesting disturbances in the autonomic nervous system. Earlier studies have pointed to a coexistence of autonomic disturbances in the enteric and cardiovascular nervous system.

Thirteen consecutive patients (age range 23 to 79, mean 44 y) fulfilling the criteria for chronic intestinal pseudo-obstruction were investigated. Six of them complained of sweating or a feeling of cold. Examination of autonomic reflexes included heart rate variation to deep-breathing (expiration/inspiration index), heart rate reaction to tilt (acceleration index, brake index), and vasoconstriction (VAC) due to indirect cooling by laser doppler (VAC-index; high index indicates impaired VAC). Test results in patients were compared with healthy individuals.

Patients had significantly higher (more abnormal) median VAC-index compared with healthy controls [1.79 (interquartile ranges 1.89) vs. 0.08 (interquartile ranges 1.29); P=0.0007]. However, symptoms of impaired heat regulation were not related to the VAC-index. There were no differences in expiration/inspiration, acceleration index, or brake index between patients and controls.

The patients with severe gastrointestinal dysmotility showed impaired sympathetic nerve function which, however, did not seem to be associated with symptoms of impaired heat regulation.