Associations between remnant lipoprotein cholesterol and nonalcoholic fatty liver disease Background: Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disorder worldwide. NAFLD is associated with obesity and atherogenic dyslipidaemia (hypertriglyceridaemia, low serum levels of high density lipoprotein cholesterol [HDL-C] and raised levels of low density lipoprotein [LDL-C]). Remnant lipoprotein cholesterol (RLP-C) is a novel risk factor for atherosclerotic cardiovascular disease that has recently been associated with increased risk of NAFLD in adults. There are no previous studies relating RLP-C with NAFLD in adolescents. We aimed to (a) examine for associations between RLP-C and NAFLD and (b) to determine if RLP-C contributes to NAFLD risk beyond traditional metabolic syndrome risk factors, insulin resistance and adipokines. Methods: Population-based adolescents aged 17 years participating in the Raine Study participated in a cross-sectional assessment. The assessment included health questionnaires, physical assessments and fasting blood tests. Fasting blood tests included serum LDL-C, HDL-C, triglycerides, alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma glutamyl transpeptidase (GGT), glucose, insulin, leptin and adiponectin. RLP-C was calculated as total cholesterol minus LDL-C and HDL-C. Homeostasis model assessment for insulin resistance (HOMA-IR) was calculated. Abdominal ultrasound was used to examine the presence and severity of hepatic steatosis, plus abdominal subcutaneous adipose thickness (SAT) and visceral adipose thickness (VAT). Results: NAFLD was diagnosed in 176/1170 (15.1%) adolescents, after excluding excessive alcohol consumption. Adolescents with NAFLD had higher RLP-C than adolescents without NAFLD (mean [SD] 0.55 [0.28] vs. 0.47 [0.24] mmol/L). RLP-C levels increased with steatosis severity (Figure 1). RLP-C was negatively correlated with serum adiponectin but positively correlated with serum leptin, insulin, hsCRP, ALT and GGT, systolic and diastolic BP, and all measures of general and subcutaneous adiposity (p<0.05 for all) but not with VAT (p=0.06). Using multivariate logistic regression analysis, adolescents with RLP-C in the bottom quartile had a 70% reduced likelihood of NAFLD compared with those with RLP-C in the top quartile (OR 0.34, 95% CI 0.17-0.70, p=0.003), after adjusting for waist circumference, sex, serum ALT, leptin, adiponectin (that were significantly associated with NAFLD, p<0.05 for all) and HOMA-IR (non-significant, p=0.35). This relationship persisted after further adjustment for serum total cholesterol, HDL-C, LDL-C and triglycerides. Conclusions: RLP-C levels are strongly associated with the risk of NAFLD in adolescents independent of sex, abdominal obesity, serum ALT, adipocytokines, total cholesterol, HDL-C and LDL-C and insulin resistance. Figure 1.
|Number of pages||2|
|Journal||Journal of Gastroenterology and Hepatology|
|Publication status||Published - Sep 2019|