<b>Objective</b>: Type 2 diabetes mellitus (T2DM) is characterized by
insulin resistance (IR) and beta-cell dysfunction. Ectopic fat accumulation in
liver and muscle causes IR. Since bariatric and metabolic surgery significantly
improves fatty liver disease, <a>we hypothesized that coexistence
of liver steatosis (i.e., when hepatic IR contributes in T2DM) would be
associated with greater diabetes improvement after surgery.</a>
<p> </p>
<p><b>Research design
and methods</b>: A total of 519
patients with T2DM who underwent Roux-en-Y gastric bypass and simultaneous
liver biopsy and had a minimum 5-year follow-up were analyzed to assess the independent
association between biopsy-proven liver steatosis and postoperative long-term
diabetes remission (glycated hemoglobin < 6.5% off medications).</p>
<p> </p>
<p><b>Results</b>: Of the 407 patients with biopsy-proven liver
steatosis, long-term diabetes remission was achieved in 211 (52%) patients,
compared with 44/112 (39%) remission in patients without steatosis
(P=0.027). In multivariable analysis, presence
of liver steatosis was an independent predictor of long-term diabetes remission
(odds ratio 1.96, [95% confidence interval 1.04 – 3.72], <i>P</i>=0.038). Hepatocyte
ballooning, lobular inflammation, or fibrosis at baseline did not predict
diabetes remission.</p>
<p> </p>
<p><b>Conclusion</b>: This study, for the first time, suggests that in
patients with T2DM who are considering bariatric and metabolic surgery,
coexistence of liver steatosis is associated with better long-term glycemic
outcomes. Furthermore, our data suggest that there are different variants of
T2DM wherein metabolic responses to surgical weight loss are different. A
subgroup of patients whose T2DM is characterized by the presence of hepatic
steatosis (presumably associated with worse IR) experience better postoperative
metabolic outcomes.</p>