Terri M Menser, PhD, Jose Muniz Castro, Bita Kash, PhD, Vadim Sherman, Nabil Tariq, MD. Houston Methodist Hospital
INTRODUCTION: Following bariatric surgery, ongoing postoperative testing is required to measure nutritional deficiencies; the purpose of this study was to quantify the prevalence of these nutritional deficiencies based on two-year of follow-up tests at frequent time points. The guidelines for postsurgical tests following bariatric procedures in the U.S. have remained unchanged for the last decade. They call for frequent and comprehensive labs that can add up to significant cost.
METHODS AND PROCEDURES: A retrospective data analysis was conducted of all laboratory tests for bariatric patients who underwent surgery between January 2016 and January 2018 (n=847). These included a CBC, CMP, Vitamins A, B1, B12, D, folate, Zinc, copper, iron studies etc. Results were categorized into 4 time periods based on time elapsed since the procedure date (i.e. 6 months, 12 months, 18 months, and 24 months). Binary variables were created for each laboratory result to calculate descriptive statistics of abnormalities for each test over time.
RESULTS: Multiple lab tests indicated a low frequency of abnormalities at 6 month, 12 month, 18 months and 24 months. Vitamin A was found to be low in only 2.5 %, 1.9% ,0% and 0% respectively. Vitamin B1 was low in 8.6%, 7.7 %, 6.7% and 4.2%. Folate was low in 4%, 4.4%, 0% and 3.7%. Vitamin B12 in 1.3%, 0.5%, 0% and 0%. Copper in 1%, 1.7%, 2.7% and 4.6%, all respectively. Multiple other labs such as TSH, T4, zinc, calcium, total protein, total iron binding capacity etc. were low in less than 10% of the patients at all time points and lower than 5% of patients at several points. No significant difference was found in Vitamins B1, B12 and folate levels between restrictive procedures like the sleeve gastrectomy and gastric bypass patients with the 2 types of procedures found in around equal prevalence in our cohort. Cost ranges from around $40 to $200 for a single one of these tests at a single time point.
CONCLUSION(S): We found the vast majority of these expensive tests to be normal at multiple time points. The frequency of current testing may be redundant, which cost patients to expend potentially unnecessary time and increases the overall cost of care. We will further try to define which patient or procedure characteristics can predict abnormalities. Future research should focus on defining cost effective postoperative lab testing guidelines for bariatric patients.
Presented at the SAGES 2017 Annual Meeting in Houston, TX.
Abstract ID: 95270
Program Number: S113
Presentation Session: Bariatric III – Optimizing Care and Pathways
Presentation Type: Podium