Abstract
CONTEXT Postprandial hypoglycemia after gastric bypass surgery is a serious problem. Available treatments are often ineffective. OBJECTIVE The objective was to test the hypotheses that injection of rapid-acting insulin before a high-carbohydrate meal or replacement of other carbohydrates with fructose in the meal would prevent hypoglycemia. DESIGN This was a randomized, crossover trial comparing a high-carbohydrate meal with premeal saline injection (control), a high-carbohydrate meal with premeal insulin injection, and a high-fructose meal with total carbohydrate content similar to the control meal. SETTING The setting was an academic medical center. PATIENTS Ten patients with post-gastric bypass hyperinsulinemic hypoglycemia participated. INTERVENTIONS Interventions included lispro insulin injected before test meals and replacement of other carbohydrates with fructose in test meals. MAIN OUTCOME MEASURE The main outcome measure was plasma glucose < 60 mg/dL after test meals. RESULTS After the control meal, mean peak glucose and insulin were 173 ± 47 mg/dL and 134 ± 55 mU/L, respectively; mean glucose nadir was 44 ± 15 mg/dL; and eight of 10 subjects demonstrated glucose < 60 mg/dL. Five subjects demonstrated a glucose nadir < 40 mg/dL. There were no significant differences in the corresponding values after premeal insulin treatment, except that the mean glucose nadir of 34 ± 10 mg/dL was lower (P < .05). After the fructose meal, mean peak postprandial glucose and insulin were 117 ± 20 mg/dL and 45 ± 31 mU/L, respectively (both P < .001 for comparison with control), mean glucose nadir was 67 ± 10 mg/dL (P < .001), and two of 10 subjects demonstrated glucose < 60 mg/dL (P < .05). CONCLUSIONS People with post-gastric bypass hypoglycemia can consume a meal sweetened with fructose with little risk of hypoglycemia. Treatment with rapid-acting insulin before a carbohydrate-containing meal did not prevent hypoglycemia.
