Symptomatic Hypoglycemia After Gastric Bypass: Incidence and Predictive Factors in a Cohort of 1,138 Consecutive Patients.

Objective: After Roux-en-Y gastric bypass (RYGB), postprandial hyperinsulinemic hypoglycemia (PPHH) is particularly critical because of the risk of trauma. The aim of this study was to assess the incidence and identify risk factors for symptomatic PPHH.

Methods: Patients with RYGB were classified into moderate PPHH (MH) or severe hypoglycemia (SH), which is defined as patients with neuroglycopenic symptoms. Logistic multivariate linear regressions were performed to identify predictive factors for symptomatic PPHH and more specifically for SH with neuroglycopenic symptoms. Patients with diabetes and those with a follow-up shorter than 2 years were excluded.

Results: Among the 1,138 patients, 44.2% had at least one episode of hypoglycemia with a mean delay of 25.5 (21.3) months, 32.6% had MH, and 11.6% had SH. The annual incidence rate of SH was 2.5% the first year, 3.7% the second year, and 1.5% the third year. Independent predictive factors for higher risk of SH were: younger age (odds ratio [OR] = 1.01; 95% CI: 1.05-16.69; P = 0.0007), lower BMI after RYGB (OR = 1.61; 95% CI: 1.17-2.22; P = 0.0035), and maximal weight loss (OR = 1.04; 95% CI = 1.39-1.23; P = 0.0106), whereas higher preoperative BMI was protective (OR = 0.78; 95% CI: 0.64-0.95; P = 0.0112).

Conclusions: This observational cohort study showed that the incidence of severe PPHH with neuroglycopenic symptoms after RYGB was higher than expected.