Changes in alanine aminotransferase in adults with severe and complicated obesity during a milk-based meal replacement programme

Razk Abdalgwad,Francis Martin Finucane,Paula Mary O’Shea,Mohammed Faraz Rafey,Iulia Ioana,Eoin Slattery,Derek Timothy O’Keeffe,Conor Murphy,Colin Davenport

doi:10.1186/s12986-020-00512-5

Abstract

IntroductionExcess adiposity is associated with fat accumulation within the liver, and non-alcoholic steatohepatitis (NASH) is highly prevalent in bariatric patients. Elevated alanine aminotransferase (ALT) is associated with prevalent NASH. We sought to determine the influence of a milk-based meal replacement weight-loss programme on ALT levels in adults with severe and complicated obesity.MethodsWe conducted a retrospective cohort study of patients who completed a 24-week meal replacement programme, comprised of a weight loss phase followed by weight stabilisation and maintenance phases, each 8 weeks long. ALT was quantified using an enzymatic assay with spectrophotometric detection. We examined changes over time in ALT using the non-parametric Wilcoxon singed-rank test and the Friedman test.ResultsOf 105 patients, 56 were female, mean age was 51.2 ± 11.2 (range 18.0–71.6) years. There was an unanticipated but transient increase in ALT from 28.0 [20.0, 40.5] iu/L at baseline to 40.0 [26.0, 55.0] iu/L after 2 weeks (p < 0.0005), followed by a gradual reduction to 21.0 [17.0, 28.3] iu/L by 24 weeks (p < 0.0005). The overall reductions in ALT were more pronounced in patients who had elevated levels at baseline. Body weight decreased from 144.2 ± 28.0 kg at baseline to 121.6 ± 25.4 kg at 24 weeks (p < 0.0005) and body mass index (BMI) decreased from 50.7 ± 8.1 kg m−2 at baseline to 43.0 ± 7.6 kg m−2 by 24 weeks (p < 0.0005).ConclusionIn adults with severe and complicated obesity undergoing a milk-based meal replacement programme, there was an initial unanticipated rise in ALT in the first 2 weeks, followed by a gradual overall reduction by 24 weeks. These findings suggest that rapid weight loss secondary to significant caloric restriction might induce a transient deterioration in hepatic steatosis prior to an ultimate overall improvement.

Highlights

Excess adiposity is associated with fat accumulation within the liver, and non-alcoholic steatohepatitis (NASH) is highly prevalent in bariatric patients
Non-alcoholic fatty liver disease (NAFLD) and NASH are highly prevalent amongst patients with obesity [9,10,11,12] and approximately 50% of people affected by obesity have elevated levels of Alanine aminotransferase (ALT) and co-existing NAFLD [13]
Elevated ALT is an independent predictor of prevalent NAFLD and there is a significant association between elevated ALT and NASH and liver fibrosis [14]

Summary

Introduction

Excess adiposity is associated with fat accumulation within the liver, and non-alcoholic steatohepatitis (NASH) is highly prevalent in bariatric patients. Elevated alanine aminotransferase (ALT) is associated with prevalent NASH. Elevated ALT is an independent predictor of prevalent NAFLD and there is a significant association between elevated ALT and NASH and liver fibrosis [14]. Most interventions to reduce body weight in patients who are overweight or obese tend to lead to improvements in NAFLD. Patients with severe obesity undergoing omega loop gastric bypass had a significant increase in ALT whereas those undergoing sleeve gastrectomy or Roux-en-Y gastric bypass had a reduction in ALT [16]. Weight loss interventions based on either increased physical activity, dietary restriction or a combination of the two, have been shown to reduce ALT in meta-analyses [18, 19]. Intensive caloric restriction such as with a very low-calorie diet has been associated with increased ALT in one study [20]

Methods

Results

Discussion

Conclusion