Diabetic gastroparesis is associated with an abnormality in sympathetic innervation

Abstract

Objective To investigate the hypothesis that diabetic gastroparesis might be associated with sympathetic, as well as parasympathetic, autonomic nervous system abnormailites. Patients We evaluated 12 consecutive patients with diabetes mellitus who presented with symptoms of gastroparesis. Methods The autonomic function tests included two measurments of sympathetic adrenergic function [reflex vasoconstriction to cold stress and the postural adjustment ratio (PAR)], and measurement of sympathetic cholinergic function (resting skin temperature) and vagal cholinergic function [EKG R-R interval (RRI)]. Gastric emptying was also measured and analysed by a power exponential model to estimate the solid gastric emptying slope. Patients were separated into delayed and nondelayed solid gastric emptying subgroups, the latter including two patients with rapid gastric emptying. Results All autonmic function measures were significantly lower in the diabetes mellitus group than in normal controls (P <0.001); diabetic patients as a group had slower solid gastric emptying slopes than nondiabetic controls (P ≤0.01). There was no significant correlation between measures of vagal cholinergic function by RRI, the sympathetic cholinergic function by PAR, or sympathetic cholinergic function by skin temperature and solid gastric emptying, but a statistically significant correlation was found between the sympathetic adrenergic measure of vasoconstriction to cold stress and the slope of solid gastric emptying (r = 0.79, P 7ge; 0.01). Diagnostic values for the autonomic function tests when compared to solid gastric emptying revealed sensitivites of 50% for the RRI, 88% for vasoconstriction, 63% for PAR and 71% for skin temperature. Conclusion We recommend that autonomic function measurements in patients with diabetes mellitus and upper gut symptoms should incude tests of sympathetic function as well as traditional tests of vagal cholinergic function.