Metabolic factors are associated with serum alanine aminotransferase levels in patients with chronic hepatitis C

Abstract

Although serum alanine aminotransferase (ALT) activity is an important marker for the management of chronic hepatitis C (CHC), the factors associated with serum ALT levels remain to be fully understood. This study aimed to clarify the association between serum ALT levels and clinical, histological, and virological factors in patients with CHC. We retrospectively analyzed 256 patients with CHC who underwent liver biopsy, and classified them into three groups according to serum ALT levels: normal to minimal (<40 IU/L), mild (40-80 IU/L), and moderate to severe elevation (≥80 IU/L). All demographic and laboratory data were collected at the time of liver biopsy. All biopsies were evaluated for fibrosis, inflammation, and steatosis. Glucose metabolism was assessed by various indices derived from oral glucose tolerance tests, including the homeostasis model assessment for insulin resistance (HOMA-IR). In 180 patients, visceral fat area was measured at the umbilical level by abdominal computed tomography. Ordered logistic regression analysis showed that higher serum ALT levels were significantly associated with male sex, lower high-density lipoprotein cholesterol (HDL-C), higher HOMA-IR, and higher grades of histological inflammation and steatosis. HOMA-IR, HDL-C, and hepatic steatosis were associated with visceral fat accumulation. Metabolic factors, as well as sex and hepatic inflammation, are independent risk factors for serum ALT elevation in hepatitis C virus (HCV)-infected patients. Metabolic factors may offer targets to decrease serum ALT levels.