Waist-to-calf circumstance ratio is an independent predictor of hepatic steatosis and fibrosis in patients with type 2 diabetes

Abstract

Background and aim: Although a combination of central obesity and decreased skeletal muscle mass has been associated with various cardiometabolic disorders, its influence on the presence of non-alcoholic fatty liver disease (NAFLD) in type 2 diabetes (T2D) is unclear. We investigated whether waist-to-calf circumference ratio (WCR) predicts NAFLD or hepatic fibrosis in T2D.

Methods: Patients with T2D (n = 5507) were enrolled in this study. Hepatic steatosis was diagnosed using abdominal ultrasound and predicting score. NAFLD was defined as 'hepatic steatosis absent other causes of chronic liver disease,' such as virus or alcoholism. Degree of hepatic fibrosis was calculated using non-invasive serum biomarker-based models. Insulin resistance was assessed by short insulin tolerance test.

Results: The prevalence of NAFLD and obesity (BMI ≥ 25 kg/m² , Asian definition) were 46.4% and 38.9%, respectively. NAFLD prevalence was higher with increasing WCR tertiles: lowest tertile (36% in men, 28% in women) versus highest tertile (53.8% in men, 58.2% in women, both P < 0.001 after stratification by insulin resistance status. Increasing WCR tertiles were independently associated with presence of NAFLD: odds ratio (OR) = 1.43, 95% confidence interval (CI) = 1.22-1.68 and OR = 1.56, 95% CI = 1.31-1.86, in the middle and highest tertiles, respectively. Furthermore, patients with NAFLD and the highest WCR tertile had significant fibrosis (OR = 8.62, 95% CI = 1.39-53.36, P = 0.021). Also, WCR was correlated with risk of sarcopenia (OR = 3.18, 95% CI = 2.50-4.05, P < 0.001, highest tertile).

Conclusions: Higher WCR is associated with increased risk of NAFLD and hepatic fibrosis independent of insulin resistance. This suggests that WCR may be a useful index to predict high risk of hepatic steatosis in T2D.

Keywords: calf circumstance; non-alcoholic fatty liver disease; non-alcoholic steatohepatitis; type 2 diabetes mellitus; waist circumstance; waist-to-calf ratio.