Improvement of nonalcoholic fatty liver disease in morbidly obese patients after sleeve gastrectomy: association of ultrasonographic findings with lipid profile and liver enzymes

Abstract

Background: After bariatric surgery an improvement or even complete resolution of nonalcoholic fatty liver disease (NAFLD) in morbidly obese patients is achieved, but little is known about the effect of laparoscopic sleeve gastrectomy (LSG).

Patients and methods: A prospective observational study of patients undergoing LSG was performed. An abdominal ultrasonography and blood sample extraction (investigating liver enzymes and lipid profile) were performed preoperatively and 12 months after surgery.

Results: Fifty patients were included in the study. Preoperatively, 84% of the patients presented liver steatosis. A significant reduction of steatosis could be observed 12 months after surgery (p < .001). Preoperative degree of steatosis showed a direct correlation with AST (p = .008) and ALT (p = .007) and an inverse correlation with HDL-cholesterol (p = .019). The reduction of liver steatosis showed an inverse correlation with the increase of HDL-cholesterol between pre- and postoperative determinations (p = .008).

Conclusions: Liver steatosis, as measured by ultrasonography, improves after sleeve gastrectomy, achieving a complete resolution in 90% of the cases. Preoperative steatosis correlates directly with AST and ALT levels and inversely with HDL-cholesterol. The postoperative increase of HDL-cholesterol shows an inverse correlation with liver steatosis improvement, suggesting that it could be a good marker for monitoring the postoperative liver status.

Keywords: Liver steatosis; liver enzymes; nonalcoholic fatty liver disease; ultrasonography.