Oral Presentation ANZOS-ASLM-ICCR 2019

Is there a high prevalence of nonalcoholic steatohepatitis (NASH) with fibrosis in individuals undergoing bariatric surgery? – a retrospective cohort study. (#112)

Samantha Hocking 1 2 3 , Janet Franklin 3 , Elisia Manson 3 , Nic Kormas 4 5 , Michelle Tan 1 2 , David Martin 6 7 , Craig Taylor 6 , Philip Le Page 6 , David Joseph 6 7 , Ian Caterson 1 3 , Tania Markovic 1 3
  1. Boden Initiative, Charles Perkins Centre, University of Sydney, Sydney, NSW, Australia
  2. Central Clinical School, Faculty of Medicine and Health, University of Sydney, Sydney, NSW, Australia
  3. Metabolism and Obesity Services, Royal Prince Alfred Hospital, Sydney Local Health District, Sydney, NSW, Australia
  4. Department of Endocrinology & Metabolism, Concord Repatriation General Hospital, Concord, NSW, Australia
  5. Diabetes, Metabolism & Obesity Translational Research Unit, Camden Hospital, Sydney, NSW, Australia
  6. Department of Upper GI Surgery, Concord Repatriation General Hospital, Sydney, NSW, Australia
  7. Hepatobiliary & Upper GIT Surgery, Royal Prince Alfred Hospital,, Sydney, NSW, Australia

Background: Obesity is a known risk factor for nonalcoholic fatty liver disease (NAFLD) with an estimated prevalence of 85% in individuals with morbid obesity. NAFLD can lead to nonalcoholic steatohepatitis (NASH) and fibrosis that can progress to cirrhosis. Among individuals undergoing bariatric surgery the prevalence of NAFLD, NASH and fibrosis remains uncertain. We sought to determine the prevalence of advanced fibrosis in a retrospective cohort undergoing bariatric surgery using two non-invasive tests for fibrosis, NAFLD score and FIB-4 score.

Method: A retrospective cohort of individuals undergoing bariatric surgery in Sydney Local Health District between January 2009 and December 2016 was identified. NAFLD fibrosis score and Fib-4 score were calculated to determine the prevalence of advanced fibrosis prior to bariatric surgery.

Results: 140 individuals underwent bariatric surgery. Mean age was 52.1 years, mean BMI 48.3 kg/m2(range 33.9 – 78.8 kg/m2) and most were female (65%) and had type 2 diabetes at baseline (65%). NAFLD fibrosis score and FIB-4 score were calculated prior to bariatric surgery for 134 individuals (6 were excluded due to missing data). Mean NAFLD fibrosis score was 0.25 (range -4.29 – 3.80) and mean FIB-4 score was 1.03 range (0.22– 6.34). 51 individuals (38%) had a NAFLD fibrosis score >0.675 suggesting severe fibrosis or cirrhosis. Of these individuals 80% had type 2 diabetes. 18 individuals (13%) had a FIB-4 score >1.45 suggesting Ishak stage 2 or higher fibrosis. Of these, 14 individuals (78%) had type 2 diabetes.

Conclusion: Non-invasive tests for fibrosis indicate that NASH fibrosis may affect up to 38% of individuals undergoing bariatric surgery. Type 2 diabetes is strongly associated with the presence of fibrosis. Non-invasive tests for fibrosis may be helpful prior to bariatric surgery to identify individuals at risk for NASH fibrosis who may benefit from intra-operative liver biopsy to diagnose liver disease.