Severity of nonalcoholic fatty liver disease and progression to cirrhosis are associated with atherogenic lipoprotein profile.

BACKGROUND & AIMS: Nonalcoholic fatty liver disease (NAFLD) is associated independently with increased cardiovascular mortality. Although NAFLD is associated with dyslipidemia, it is not clear whether recently identified markers of cardiovascular risk indicate liver disease progression in patients with histologically confirmed NAFLD. We evaluated an extensive panel of serum markers of cardiovascular risk in nondiabetic patients with histologically proven NAFLD.

METHODS: We performed a case-control study in which we compared serum levels of laboratory markers of cardiovascular risk among 81 nondiabetic subjects with histologically confirmed NAFLD vs lean (N = 81) and obese (N = 81) individuals without NAFLD (based on liver fat score, controls). For ex vivo studies, liver tissues were obtained from subjects undergoing elective cholecystectomy or from a tissue repository.

RESULTS: Subjects with NAFLD had increased serum levels of insulin, triglycerides, and apolipoprotein B; increased size and concentration of very large density lipoprotein particles; increased concentrations of low-density lipoprotein (LDL) particles and small dense LDL (sdLDL) cholesterol, and an increased percentage of sdLDL, compared with controls. Although nonalcoholic steatohepatitis was associated with a worse profile of serum atherogenic markers than NAFLD, these differences did not reach statistical significance. Despite hyperinsulinemia, triglyceride and apolipoprotein B levels, concentrations of LDL particles and LDL cholesterol, and sdLDL-related parameters decreased significantly in patients with cirrhosis. Ex vivo studies showed that patients with NAFLD had increased sensitivity of hepatic triglyceride levels and cholesterol synthesis to insulin, and that sensitivity increased the development of cirrhosis.

CONCLUSIONS: Atherogenic dyslipidemia is related to increased insulin-induced hepatic lipid synthesis in patients with NAFLD. Reduced dyslipidemia in patients with cirrhosis is associated with increased insulin resistance and possibly failed lipid synthesis.