Non-high-density lipoprotein cholesterol as a biomarker for nonalcoholic steatohepatitis

Background & aims: There are no clinically available biomarkers for nonalcoholic steatohepatitis (NASH); differentiating between steatosis and NASH requires histologic evaluation. Noninvasive methods are needed to replace liver biopsy and its associated risks. Production of very low density lipoprotein (VLDL) contributes to the development of NASH and might be used to distinguish steatosis from NASH. However, it is not possible to measure levels of VLDL directly in the clinic. Non-high-density lipoprotein-cholesterol (non-HDL-C) encompasses all apolipoprotein-B-containing lipoproteins, including VLDL, and can be calculated from standard lipid panels without additional cost.

Methods: We evaluated the ability of non-HDL-C to differentiate steatosis from NASH in a prospective study of 218 patients with suspected NASH (steatosis, n = 100 and NASH, n = 118).

Results: Patients with NASH had a trend toward increased levels of non-HDL-C, compared with those with steatosis (P = .08). However, among subjects not on lipid-lowering medications, those with NASH had significantly higher levels of non-HDL-C (144.6 mg/dL) than those with steatosis (129.3 mg/dL; P = .025). This difference remained significant when adjusted for levels of cholesterol and triglycerides, indicating that the difference results from increased levels of apolipoprotein B including VLDL. These findings were validated in a cohort of 40 patients with steatosis or NASH who were not taking lipid-lowering agents. The NASH group had significantly higher levels of non-HDL-C than the steatosis group (162.8 vs 145.9 mg/dL; P = .04).

Conclusions: NASH is associated with significantly higher levels of non-HDL-C than steatosis in patients who do not take lipid-lowering agents. This low-cost biomarker could be used in noninvasive differentiation between steatosis and NASH.