Background: Non-alcoholic steatohepatitis (NASH) is an advanced form of nonalcoholic fatty liver disease that can lead to liver failure. NASH is associated with morbid obesity, cardiac risk factor abnormalities, and metabolic syndrome. Gastric bypass surgery provides resolution of excess weight and cardiac risk factors. The aim of our study was to determine if a NASH diagnosis affected either resolution of excess weight or cardiac risk factors after gastric bypass surgery.
Methods: We obtained intra-operative liver biopsies in 142 laparoscopic gastric bypass surgery patients. We assessed comorbidities such as alcohol use, hypertension, diabetes, and hepatitis. In addition, weight loss and biochemical cardiac risk factors were assessed pre-operatively and at 3, 6, and 12 months. These cardiac risk factors included total cholesterol (TC), low density lipoprotein cholesterol (LDL), high-density lipoprotein cholesterol (HDL), triglycerides (TRG), C-reactive protein (CRP), Lipoprotein a (LPA), Homocysteine (HC), hemoglobin A1C (HGA) and a novel marker of insulin resistance, ratio of triglycerides to HDL (TG/HDL). All patients abstained from statin therapy after surgery until the 12 month assessment. We dichotomized liver pathology into NASH vs Steatosis (SS) per Brunt criteria for analysis by T-test or Chi- Square analysis as appropriate.
Results: Patient demographics were mean age, 45; female, 88%; mean BMI, 47; diabetic, 38%; hypertensive, 62%; and hepatitis or alcohol abuse, 0%. Liver biopsy results were Normal (2%), Steatosis (60%) and NASH (38%). Preoperative cardiac risk factors were equivalent between NASH and Steatosis. There were no significant differences in the following biochemical cardiac risk factors at 12 months for NASH vs Steatosis: TC, LDL, HDL, TRG, LPA, HC, HGA, and TRG/HDL. Significant differences did exist between NASH and Steatosis for HDL and TG/HDL at 3 months (NASH/SS, p-value): HDL (36/41, 0.04), TG/HDL (3.8/2.9, 0.03). In addition, there was a significant difference between NASH and Steatosis at 12 months for CRP (NASH/SS, p-value): (2/5, 0.05). There was no significant difference for percent excess weight loss at 12 months for the two groups (NASH/SS, p-value): (69/71, 0.78).
Conclusion: This study demonstrates that neither weight loss nor cardiac risk factor resolution after gastric bypass is affected by the diagnosis of NASH. However, improved CRP resolution is correlated with NASH. This novel finding underscores the relationship between CRP and NASH.