Gastroesophageal reflux in diabetes mellitus

Although abnormal gastroesophageal (GE) reflux is the most frequent alteration of the gastrointestinal tract, its prevalence in diabetes mellitus (DM) is not widely known. The objective of this study was to analyze both the presence of abnormal GE reflux in diabetic patients with no esophageal symptoms and the influence of cardiovascular autonomic neuropathy (CVAN) in the development of abnormal GE reflux.

Fifty insulin-dependent diabetic patients, averaging 29.2 +/- 9.0 yr of age, who had had diabetes for > 5 yr and showed no symptoms or history of gastroesophageal disease, were compared with a control group composed of 36 healthy volunteers (18 men, 18 women) whose average age was 35.9 +/- 10.1 yr. The cardiovascular autonomic nervous system was examined in the diabetics and control subjects who complied with inclusion criteria. Long-term (24-h) ambulatory esophageal pH monitoring was performed, as well as a manometric study of the lower esophageal sphincter.

The parameters obtained from the monitoring showed significant differences (p < 0.01) between DM and control subjects. Abnormal GE reflux, defined as any percentage of time with esophageal pH < 4 exceeding 3.5% of total time (8.7 +/- 5.6%; range, 4.1-24.4%), was detected in 14 patients. Diabetic subjects were classified according to cardiovascular autonomic neuropathy tests (without CVAN [n = 19, 38%] and with abnormal CVAN tests [n = 31, 62%]). The pH monitoring parameters showed significant differences between these two groups (p < 0.05).

A higher prevalence (28%) of abnormal GE reflux appeared among asymptomatic diabetic patients than among the general population. The presence of abnormal GE reflux in diabetic patients was associated with the existence of cardiovascular autonomic neuropathy (abnormal GE reflux = 38.7% in diabetic patients with abnormal CVAN tests vs 10.5% in diabetic patients without CVAN).