Bariatric surgery in patients with type 1 diabetes: special considerations are warranted

We examined short and long-term outcomes of bariatric surgery in patients with obesity and type 1 diabetes mellitus (T1DM).

We reviewed the records of all adults insured by Maccabi Healthcare Services during 2010 -2015, with body mass index (BMI) ⩾30 kg/m2 and T1DM; and compared weight reduction and glucose control according to the performance of bariatric surgery. BMI and glycated hemoglobin (HbA1c) levels were extracted for baseline and every 6 months, for a mean 3.5 years.

Of 52 patients, 26(50%) underwent bariatric surgery. Those who underwent surgery were more often female and with a longer duration of diabetes. Immediately postoperative, 4(15%) developed diabetic ketoacidosis, while 6(23%) experienced severe hypoglycemic episodes. The mean BMI decreased among surgery patients: from 39.5±4.4 to 30.1±5.0 kg/m2 (p < 0.0001); and increased among those who did not undergo surgery: from 33.6±3.9 to 35.1±4.4 kg/m2 (p = 0.49). The mean HbA1c level decreased during the first 6 months postoperative: from 8.5±0.9% to 7.9±0.9%; however, at the end of follow-up, was similar to baseline, 8.6±2.0% (p = 0.87). For patients who did not undergo surgery, the mean HbA1c increased from 7.9±1.9% to 8.6±1.5% (p = 0.09).

Among individuals with obesity and T1DM, weight loss was successful after bariatric surgery, but glucose control did not improve. The postoperative risks of diabetic ketoacidosis and severe hypoglycemic episodes should be considering when performing bariatric surgery in this population.