Combined Non-alcoholic Fatty Liver Disease and Type 2 Diabetes Mellitus: Sleeve Gastrectomy or Gastric Bypass?-a Controlled Matched Pair Study of 34 Patients.

INTRODUCTION: Although all bariatric procedures improve non-alcoholic fatty liver disease (NAFLD) in metabolically sick obese patients, it remains unclear whether different procedures achieve similar effects. Sleeve gastrectomy (SG) and Roux-Y-gastric bypass (RYGB) were compared for their effects on liver function tests (LFT) and glycemic control in a highly selected group of metabolically sick obese patients with both elevated alanine aminotransferase (ALT), a common marker for NAFLD and type 2 diabetes mellitus (T2DM). METHODS: Thirty-four obese patients with a body mass index (BMI) >35 kg/m(2), ALT > 35 U/L, and T2DM were well-matched from a prospective database and retrospectively analyzed. Seventeen patients each underwent RYGB and SG, respectively. The effects on LFT and glycemic control were evaluated over 12 months. RESULTS: Both procedures significantly lowered ALT and aspartate aminotransferase (AST) after 12 months, but SG improved both LFT significantly better than RYGB (ALT 17.8 ± 8.8 vs. 31.1 ± 11.2 U/L, p = 0.003; AST 17.0 ± 8.8 vs. 24.3 ± 7.5 U/L, p = 0.004). In contrast to RYGB, SG normalized elevated ALT levels completely (41 vs. 0 %, p = 0.007). Both SG and RYGB improved insulin resistance, glycemic control, and reduced the need of insulin significantly without any difference between the procedures. CONCLUSION: SG appears to improve LFT better than RYGB in well-matched obese patients with both elevated ALT and T2DM. This suggests that SG may have a better effect on NAFLD than RYGB with similar effects on glycemic control. The present findings should be verified in randomized controlled trials to obtain further evidence for the decision-making on the most appropriate bariatric procedure for metabolically sick patients.