Decreased sympathetic inhibition in gastroesophageal reflux disease

This study was undertaken to evaluate autonomic nervous system function in patients with gastroesophageal reflux disease. Based on clinical criteria, 28 consecutive patients with no history of heart, metabolic, or neurologic disease (mean age 41 y, range 20-62 y) reporting with upper gastrointestina l symptoms typical of gastroesophageal reflux underwent esophageal manometr y, ambulatory 24-hour pH study with electrocardiographic monitoring, power spectral analysis of heart rate variability, and cardiovascular tests. Twel ve healthy subjects served as controls. A positive result of prolonged esop hageal pH study (pH in the distal esophagus less than 4, lasting more than 4.2% of recording time) was observed in 21 patients (reflux group); seven p atients were categorized in the nonreflux group. No patient showed arrhythm ias or any correlation between heart rate variability changes during electr ocardiographic monitoring and episodes of reflux (pH less than 4, lasting m ore than 5 minutes). A decrease of sympathetic function occurred only in th e reflux group (p < 0.05) supported by the lower increase of systolic/diast olic blood pressure at sustained handgrip. No other cardiovascular tests sh owed statistically significant differences in the control or nonreflux grou ps. Total time reflux showed an inverse correlation with sympathetic functi on in the reflux group (r = -0.415, p < 0.028). We concluded that there is some evidence for a slightly decreased sympathetic function in patients wit h gastroesophageal. reflux disease that is inversely correlated with total time reflux. In these patients, decreased sympathetic function may cause dy sfunction of intrinsic inhibitory control with increased transient spontane ous lower-esophageal sphincter relaxations, thus resulting in gastroesophag eal reflux disease.