LIVER ABNORMALITIES IN SEVERELY OBESE SUBJECTS - EFFECT OF DRASTIC WEIGHT-LOSS AFTER GASTROPLASTY

OBJECTIVE: To examine the factors associated with liver steatosis in s everely obese subjects and to test the potential reversibility of fatt y liver after weight loss. DESIGN: Retrospective clinical study. SUBJE CT: 528 obese patients before bariatric surgery and 69 obese subjects of the initial cohort evaluated before and 27 +/- 15 months after gast roplasty. MEASUREMENTS: Fatty deposition (scored as mild, moderate or severe) and inflammatory changes were evaluated in liver biopsies; cli nical (body mass index (BMI), age, gender, duration of obesity) and bi ological (glucose, triglycerides, liver enzymes) parameters were relat ed to histological findings. RESULTS: 74% of the 528 biopsies showed f atty change, estimated as mild in 41% of cases, moderate in 32% and se vere in 27%. The prevalence of steatosis was significantly higher in m en than in women (91% vs 70%, P = 0.001) and in patients with impaired glucose tolerance or type 2 diabetes compared with nondiabetics (89% vs 69% P = 0.001). The severity of the steatosis was associated with B MI (P = 0.002) but not with the duration of obesity or the age of the patient. When compared with patients without fatty change, those with liver steatosis had significantly higher fasting plasma glucose (5.5 m mol/l vs 5.1 mmol/l, P = 0.007) and triglycerides (1.8 mmol/l vs 1.3 m mol/l, P = 0.002). Mean serum liver enzyme activities (alkaline phosph atase, aspartate aminotransferase (AST), alanine aminotransferase (ALT ) and gamma-glutamyl-transpeptidase (gamma GT) were significantly (P < 0.001) increased in patients with fatty change but remained within la boratory reference values. In the 69 patients who have been evaluated after a marked weight reduction (-32 +/- 19 kg), 45% of the biopsies w ere considered as normal (vs 13% before, P < 0.001) while pure fatty c hange was still observed in 38% of the patients (vs 83% before, P = 0. 001). However, the severity of the steatosis was significantly (P < 0. 001) reduced (mild: 62% vs 21%; moderate: 23% vs 37%; severe: 15% vs 4 2%). In addition, a significant increase of hepatitis was observed in 26% of the biopsies (vs 14% before, P < 0.05). CONCLUSIONS: Liver stea tosis in obese subjects is associated with men, diabetic status, BMI, higher fasting glucose and hypertriglyceridaemia. Postgastroplasty wei ght loss reduces liver steatosis, but seems to increase the incidence of inflammatory lobular hepatitis.