Surgically induced weight loss by gastric bypass improves non alcoholic fatty liver disease in morbid obese patients

Aim: To evaluate the effects of surgical weight loss (Roux-en-Y gastric bypass with a modified Fobi-Capella technique) on non alcoholic fatty liver disease in obese patients. Methods: A group of 26 morbidly obese patients aged 45 ± 2 years and with a body mass index > 40 kg/m2 who underwent open surgical weight loss operations had paired liver biopsies, the first at surgery and the second after 16 ± 3 mo of weight loss. Biopsies were evaluated and compared in a blinded fashion. The presence of metabolic syndrome, anthropometric and biochemical variables were also assessed at baseline and at the time of the second biopsy. Results: Percentage of excess weight loss was 72.1% ± 6.6%. There was a reduction in prevalence of metabolic syndrome from 57.7% (15 patients) to 7.7% (2 patients) (P < 0.001). Any significance difference was observed in aspartate aminotransferase or alanine aminotransferase between pre and postsurgery. There were improvements in steatosis (P < 0.001), lobular (P < 0.001) and portal (P < 0.05) inflammation and fibrosis (P < 0.001) at the second biopsy. There were 25 (96.1%) patients with non alcoholic steatohepatitis (NASH) in their index biopsy and only four (15.3%) of the repeat biopsies fulfilled the criteria for NASH. The persistence of fibrosis (F > 1) was present in five patients at second biopsy. Steatosis and fibrosis at surgery were predictors of significant fibrosis postsurgery. Conculsion: Restrictive mildly malabsorptive surgery provides significant weight loss, resolution of metabolic syndrome and associated abnormal liver histological features in most obese patients. © 2012 Baishideng.