Prognostic factors in resolution of nonalcoholic fatty liver disease post bariatric surgery in adolescents

Authors: BACHA, FIDA - Children'S Nutrition Research Center (CNRC); GUPTA, RESMI - University Of Texas Health Science Center; JENKINS, TODD - Cincinnati Children'S Research Hospital; BRANDT, MARY - Tulane University; INGE, THOMAS - Northwestern University; KLEINER, DAVID - National Cancer Institute (NCI, NIH); XANTHAKOS, STAVRA - Cincinnati Children'S Research Hospital

Submitted to: Surgery for Obesity and Related Diseases
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/12/2023
Publication Date: 4/1/2024
Citation: Bacha, F., Gupta, R., Jenkins, T.M., Brandt, M.L., Inge, T.H., Kleiner, D.E., Xanthakos, S.A., for the Teen-Longitudinal Assessment of Bariatric Surgery (Teen-LABS) Consortium. 2024. Prognostic factors in resolution of nonalcoholic fatty liver disease post bariatric surgery in adolescents. Elsevier. 20(4);367-375. https://doi.org/10.1016/j.soard.2023.11.004.
DOI: https://doi.org/10.1016/j.soard.2023.11.004

Interpretive Summary: Children with severe obesity who undergo bariatric weight loss surgery often have a condition called non-alcoholic fatty liver disease (NAFLD). The effect of weight loss surgery on the improvement of NAFLD is not well known. The factors that may improve the chance of improvement in this condition after surgery are also not clear. Researchers in Houston collaborated with a national study on weight loss surgery in youth called Teen-LABS Consortium, to answer these questions. The study evaluated liver function tests in youth with obesity before and up to 2 years after surgery, and the factors that may be related to changes in liver function in response to surgery. They found that bariatric surgery resulted in improvement of liver function suggestive of improvement in NAFLD after surgery. This improvement was related to weight loss. In addition, improvement in metabolic factors such as insulin sensitivity, glucose and lipid markers also played a role in the improvement of NAFLD. This suggests an improvement in liver disease after weight loss surgery partly independent of weight loss. Additional studies are needed to follow children for a longer period and to evaluate effect of surgery on those with more severe degree of liver disease.

Technical Abstract: The long-term effect of bariatric surgery on adolescent non-alcoholic fatty liver disease is not clear. To evaluate longitudinal change in serum alanine aminotransferase (ALT) levels and to determine the factors independently associated with this change over 2 years after bariatric surgery in adolescents with severe obesity. An observational prospective cohort from the Teen-Longitudinal Assessment of Bariatric Surgery (Teen-LABS) Consortium. We examined the relationship of longitudinal change in serum ALT (% change and normalization) to change in body mass index (BMI), homeostasis model assessment of insulin resistance (HOMA-IR), triglycerides (TG), high- (HDL) and low-density lipoprotein cholesterol, A1C and fasting glucose, accounting for age, sex, race-ethnicity, blood pressure, and baseline BMI in 219 adolescents during the first 2 years post-surgery. Mean BMI declined from a baseline of 52.6 to 37.2 kg/m2 at 2 years (P<.01). Alanine aminotransferase decreased significantly from baseline (36.5 [95% CI: 31.4, 41.7]) to 6 months (30.5 [95% CI: 25.4, 35.6]), and remained stable at 12 and 24 months, all P<.01 versus baseline. After adjustment, improvement in BMI, fasting glucose, HOMA-IR, triglycerides, TG/HDL ratio, and HDL were independently associated with reduced ALT at 6 months. These remained significantly associated with a decline in ALT after adjusting for BMI change. The %participants with elevated ALT decreased from 71% at baseline to 42% and 36% at 1 and 2 years post-surgery. Bariatric surgery resulted in significant and sustained improvement in ALT levels over 2 years. Although associated with weight loss, this decline was also associated with improved metabolic indices, independent of weight loss.