A305 Prevalence of thiamine deficiency is significant in patients undergoing primary bariatric surgery.

Abstract

Bariatric patients are prone to micronutrient deficiencies, necessitating life-long nutritional supplementation and monitoring. Historically these deficiencies were thought to be driven by post-surgical changes in absorption, though recent data have demonstrated that obesity alone is also associated with micronutrient deficiencies. Despite the associated risks, many insurance plans do not cover costs associated with preoperative nutritional assessment that could identify patients prone to severe deficiencies postoperatively. Thiamine deficiency in particular can lead to permanent neurologic deficits and we aimed to identify its prevalence in our preoperative bariatric surgical patients. A retrospective review of deidentified data was examined that included whole blood thiamine measured from consecutive patients from 4/2018 to 4/2019 (n=274). Cohort characteristics were assessed including age, operation, preoperative body weight, and race/ethnicity. The majority of the cohort were women (83%) with an average age of 45.7 years. Racial representation included White/Caucasian (73%) and Black/African American (20%), while operations included Roux-en-Y gastric bypass (61%), sleeve gastrectomy (31%), and revisions (8%). Thiamine concentration was normally distributed with a mean of 146nM. Overall, 5% of patients had preoperative thiamine concentrations below the lower limit of normal (<70nM). These patients were younger (40.8 years) and were all undergoing primary procedures (50% gastric bypass, 50% sleeve gastrectomy). Quoted rates of thiamine deficiency in the preoperative patient are variable, but we describe a significant number of patients at risk for thiamine deficiency. This warrants preoperative thiamine measurement in all bariatric patients due to the potential for permanent neurologic sequelae as well as other micronutriennt assessment.