Background: Symptomatic hypoglycemia is an unavoidable problem in the treatment of type I diabetes. Celiac disease is associated with malabsorption and may therefore represent an important risk factor.
Methods: The frequency of symptomatic hypoglycemia in patients with type I diabetes and celiac disease (cases) was compared with those of patients who had diabetes without celiac disease (controls). For this purpose, each case was matched for age, sex, and duration of disease with one to two control patients. Indices of metabolic control (hemoglobin [Hb]A1c, frequency of hypoglycemia, and total insulin requirement) were retrieved for the 18 months before and after diagnosis of celiac disease.
Results: Eighteen patients (6 males and 12 females) had diagnosed celiac disease and were matched with 26 control patients (10 males and 16 females). There was no difference in age (11.0 years; range, 1.8-21.9 vs. 13.1 years; range, 2.3-22; P = 0.3) and duration of disease (8.4 years; range, 1.2-19.3 vs. 8.3 years; range, 1.1-18.7; P = 0.3) between the two groups. During the 6 months before and after diagnosis of celiac disease the cases had significantly more hypoglycemic episodes than the controls (means +/- SD; 4.5+/-4 vs. 2.0+/-2.2 episodes/months, P = 0.01). This was reflected by a progressive reduction in insulin requirement over the 12 months before diagnosis reaching a nadir at time 0 (0.6+/-0.2 vs. 0.9+/-0.3, P = 0.05).
Conclusion: These data suggest that underlying celiac disease is associated with an increased risk of symptomatic hypoglycemia and that the introduction of a gluten-free diet with normalization of the intestinal mucosa may reduce its frequency.