Introduction: There is a strong bidirectional relationship between nonalcoholic fatty liver disease (NAFLD) and type 2 diabetes mellitus (T2DM), both of which can lead to an increase in harmful metabolism and cardiovascular risk. It was discovered that C1q/TNF-related protein 4 (CTRP4) regulates glucolipid metabolism and feeding behavior. However, the correlation between serum CTRP4 and NAFLD in T2DM patients is not yet fully understood. Methods: This study enrolled 188 T2DM participants who were separated into 2 distinct groups (NAFLD and non-NAFLD) according to abdominal ultrasound imaging results. The enzyme-linked immunosorbent assay was utilized to evaluate the levels of serum CTRP4. Clinical data and CTRP4 concentration were compared between the two groups. Linear and logistic regression analyses were performed to evaluate the correlation of serum CTRP4 levels with NAFLD risk in T2DM patients. Results: Compared with non-NAFLD, the concentration of CTRP4 was lower in NAFLD group (median 2.46 vs. 2.89, P < 0.001). The log(CTRP4) value was found to be negatively correlated with alanine aminotransferase, aspartate aminotransferase, body mass index (BMI), and waist circumference in a Pearson correlation analyses (r = -0.159, -0.156, -0.224, -0.268, all P < 0.05); besides, the trend χ2 test demonstrated that the prevalence of NAFLD rose as CTRP4 concentration decreased (P < 0.001). Regression analysis suggested that NAFLD served as an independent factor influencing log(CTRP4) independently (β-coefficient = -0.12, P = 0.011), even after adjusting for high-sensitivity C-reactive protein and white blood cells. Finally, the results of the logistic regression analysis demonstrated that BMI [odds ratio (OR) = 1.196, P = 0.028], triglyceride (OR = 2.744, P < 0.001), and CTRP4 (OR = 0.615, P = 0.032) were independently associated with NAFLD in T2DM. Conclusions: T2DM patients with NAFLD have lower CTRP4 serum concentrations than those without NAFLD. The risk of NAFLD in patients with T2DM is inversely correlated with serum CTRP4 levels.
Keywords: C1q/TNF-related protein 4; nonalcoholic fatty liver disease; type 2 diabetes.