Remnant cholesterol/high-density lipoprotein cholesterol ratio is a new powerful tool for identifying non-alcoholic fatty liver disease

Lipids as potential mediators linking body mass index to diabetes: evidence from a mediation analysis based on the NAGALA cohort

BACKGROUND

Body mass index (BMI) and lipid disorders are both known to be strongly associated with the development of diabetes, however, the indirect effect of lipid parameters in the BMI-related diabetes risk is currently unknown. This study aimed to investigate the mediating role of lipid parameters in the association of BMI with diabetes risk.

METHODS

We assessed the association of diabetes risk with BMI, as well as lipid parameters including high-density lipoprotein cholesterol(HDL-C), low-density lipoprotein cholesterol(LDL-CF and LDL-CS), triglycerides(TG), total cholesterol(TC), remnant cholesterol(RC), non-HDL-C, and combined indices of lipid parameters with HDL-C (RC/HDL-C ratio, TG/HDL-C ratio, TC/HDL-C ratio, non-HDL/HDL-C ratio, LDL/HDL-C ratio) using data from 15,453 subjects in the NAGALA project. Mediation models were used to explore the mediating role of lipid parameters in the association of BMI with diabetes risk, and mediation percentages were calculated for quantifying the strength of the indirect effects. Finally, receiver operating characteristic curve (ROC) analysis was used to compare the accuracy of BMI and BMI combined with lipid parameters in predicting incident diabetes.

RESULTS

Multivariate regression models, adjusted for confounding factors, demonstrated robust associations of lipid parameters, BMI, with diabetes risk, with the exception of TC, LDL-CF, LDL-CS, and non-HDL-C. Mediation analysis showed that lipid parameters except TC, LDL-CF, LDL-CS, and Non-HDL-C were involved in and mediated the association of BMI with diabetes risk, with the largest mediation percentage being the RC/HDL-C ratio, which was as high as 40%; it is worth mentioning that HDL-C and HDL-C-related lipid ratio parameters also play an important mediating role in the association between BMI and diabetes, with the mediator proportion being greater than 30%. Finally, based on the ROC results, we found that the prediction performance of all lipid parameters in the current study except TC was significantly improved when combined with BMI.

CONCLUSION

Our fresh findings suggested that lipid parameters partially mediated the association of BMI with diabetes risk; this result indicated that in the context of diabetes risk screening and disease management, it is important to not only monitor BMI but also pay attention to lipid parameters, particularly HDL-C and HDL-C-related lipid ratio parameters.

Serum remnant cholesterol is a potential predictor of liver stiffness in patients with nonalcoholic fatty liver disease

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is associated with dyslipidemia, and the connection between dyslipidemia and remnant cholesterol (RC), a component of triglyceride-rich lipoproteins, remains enigmatic.

METHODS

In this cross-sectional study, our primary aim was to investigate the role of RC in the progression of NAFLD and to provide robust evidence of RC's involvement in the pathogenesis of NAFLD. We enrolled 2800 NAFLD patients from the National Health and Nutrition Examination Survey (NHANES). Logistic regression was employed to examine the relationship between serum RC levels and liver stiffness, while receiver operating characteristic (ROC) curve analysis was used to assess the diagnostic capability of RC.

RESULTS

RC exhibited an independent correlation with the extent of liver stiffness, with odds ratios (OR) of 1.02 for liver steatosis (p = 0.014) and 1.02 for liver fibrosis (p = 0.014). To predict NAFLD, the optimal RC thresholds were 17.25 mg/dL for males and 15.25 mg/dL for females in the case of liver steatosis. For advanced liver fibrosis, the best thresholds were 17.25 mg/dL for males and 16.25 mg/dL for females.

CONCLUSIONS

RC demonstrated a positive correlation with the degree of liver stiffness and exhibited superior diagnostic efficacy for liver steatosis and fibrosis compared to other cholesterol indicators.

Association between the remnant cholesterol to high-density lipoprotein cholesterol ratio and the risk of coronary artery disease

BACKGROUND

The purpose of this study was to evaluate the relationship between remnant cholesterol (RC) to high-density lipoprotein cholesterol (HDL-C) ratio and the risk of coronary artery disease (CAD). We also investigated the clinical value of RC/HDL-C ratio in evaluating the severity of CAD and in predicting the short-term prognosis of CAD patients.

METHODS

In total, 615 patients were enrolled and they were classified into a CAD group (418 cases) and a normal group (197 cases) according to the results of coronary angiography. Serum RC/HDL-C ratio and Gensini score were calculated. Multivariate logistic regression and receiver operating characteristic (ROC) curves were employed to evaluate the association between RC/HDL-C ratio and CAD. The effect of RC/HDL-C ratio on the progression of major adverse cardiovascular events (MACEs) was also explored.

RESULTS

Increased RC/HDL-C ratio was associated with an increased risk of CAD (OR: 11.122; 95% CI: 5.903-20.954; P  < 0.001). When stratified by CAD subtypes, increased RC/HDL-C ratio was correlated with a greater risk of acute coronary syndrome (ACS) (OR:1.549; 95% CI: 1.014-2.364; P  < 0.05). Compared with the first quartile, the 4th quartile of RC/HDL-C ratio had a 9.774-fold ( P  = 0.000) increase in the odds ratio for CAD, and a 2.241-fold ( P  = 0.017) increase in the odds ratio for ACS. RC/HDL-C ratio was an independent determinant of Gensini score ≥32 (OR: 2.138, 95% CI:1.389-3.292, P  < 0.01), and multi-branch (MVD) (OR: 2.245; 95% CI: 1.468-3.443; P  < 0.001). The prevalence of Gensini score ≥32 and MVD in the 4th quartile of RC/HDL-C ratio group were much higher than that of other quartile groups ( P  < 0.01). Moreover, the areas under the ROC for the predictive value of RC/HDL-C ratio for CAD, ACS, Gensini score ≥32, and MVD were 0.702, 0.563, 0.602, and 0.669, respectively. Furthermore, the incidence of MACEs was significantly increased in CAD patients with levels of RC/HDL-C ratio ( P  < 0.05).

CONCLUSION

RC/HDL-C ratio plays an important role in the progression and severity of CAD.

Lipid metabolism, BMI and the risk of nonalcoholic fatty liver disease in the general population: evidence from a mediation analysis

BACKGROUND

Body mass index (BMI) and lipid parameters are the most commonly used anthropometric parameters and biomarkers for assessing nonalcoholic fatty liver disease (NAFLD) risk. This study aimed to assess and quantify the mediating role of traditional and non-traditional lipid parameters on the association between BMI and NAFLD.

METHOD

Using data from 14,251 subjects from the NAGALA (NAfld in the Gifu Area, Longitudinal Analysis) study, mediation analyses were performed to explore the roles of traditional [total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C)] and non-traditional [non-HDL-C, remnant cholesterol (RC), TC/HDL-C ratio, LDL-C/HDL-C ratio, TG/HDL-C ratio, non-HDL-C/HDL-C ratio, and RC/HDL-C ratio] lipid parameters in the association of BMI with NAFLD and quantify the mediation effect of these lipid parameters on the association of BMI with NAFLD using the percentage of mediation.

RESULT

After fully adjusting for confounders, multivariate regression analysis showed that both BMI and lipid parameters were associated with NAFLD (All P-value < 0.001). Mediation analysis showed that both traditional and non-traditional lipid parameters mediated the association between BMI and NAFLD (All P-value of proportion mediate < 0.001), among which non-traditional lipid parameters such as RC, RC/HDL-C ratio, non-HDL-C/HDL-C ratio, and TC/HDL-C ratio accounted for a relatively large proportion, 11.4%, 10.8%, 10.2%, and 10.2%, respectively. Further stratified analysis according to sex, age, and BMI showed that this mediation effect only existed in normal-weight (18.5 kg/m² ≤ BMI < 25 kg/m²) people and young and middle-aged (30-59 years old) people; moreover, the mediation effects of all lipid parameters except TC accounted for a higher proportion in women than in men.

CONCLUSION

The new findings of this study showed that all lipid parameters were involved in and mediated the risk of BMI-related NAFLD, and the contribution of non-traditional lipid parameters to the mediation effect of this association was higher than that of traditional lipid parameters, especially RC, RC/HDL-C ratio, non-HDL-C/HDL-C ratio, and TC/HDL-C ratio. Based on these results, we suggest that we should focus on monitoring non-traditional lipid parameters, especially RC and RC/HDL-C ratio, when BMI intervention is needed in the process of preventing or treating NAFLD.

Utility of traditional and non-traditional lipid indicators in the diagnosis of nonalcoholic fatty liver disease in a Japanese population

BACKGROUND

Traditional and non-traditional (TNNT) lipid indicators are known to be closely related to nonalcoholic fatty liver disease (NAFLD). This study's objective was to compare the degree of associations and diagnostic values of TNNT lipid indicators with NAFLD.

METHODS

Participants were 14,251 Japanese adults who undergoing health checkups, and we measured and calculated 11 lipid indicators, including traditional lipid indicators such as high-density lipoprotein cholesterol (HDL-C), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and triglyceride (TG), as well as non-traditional lipid indicators such as TC/HDL-C ratio, LDL-C/HDL-C ratio, TG/HDL-C ratio, non-HDL-C, remnant cholesterol (RC), RC/HDL-C ratio and non-HDL-C/HDL-C ratio. The associations between these lipid indicators and NAFLD were assessed using multivariate logistic regression, and the performance of these lipid indicators in identifying NAFLD was analyzed by receiver operating characteristic (ROC) curves.

RESULTS

After rigorous adjustment for potential confounders, multivariate logistic regression showed that all TNNT lipid indicators were independently associated with NAFLD, among which the RC/HDL-C ratio and RC had the strongest association with NAFLD. ROC analysis showed that non-traditional lipid indicators were superior to traditional lipid indicators in identifying NAFLD, especially in young adults and females. It is worth mentioning that the RC/HDL-C ratio was the best lipid indicator for identifying NAFLD with an area under the curve (AUC) of 0.82 and an optimal cut-off value of 0.43; in addition, TG/HDL-C ratio also had a high recognition performance for NAFLD.

CONCLUSION

Overall, in the Japanese population, non-traditional lipid indicators had a higher diagnostic value for NAFLD compared to traditional lipid indicators, and lipid indicators alone had a lower diagnostic value for NAFLD than the ratio of two lipid indicators, with RC/HDL-C and TG/HDL-C being the best lipid indicators for identifying NAFLD.

Evaluation of the value of conventional and unconventional lipid parameters for predicting the risk of diabetes in a non-diabetic population

BACKGROUND

Conventional and unconventional lipid parameters are associated with diabetes risk, the comparative studies on lipid parameters for predicting future diabetes risk, however, are still extremely limited, and the value of conventional and unconventional lipid parameters in predicting future diabetes has not been evaluated. This study was designed to determine the predictive value of conventional and unconventional lipid parameters for the future development of diabetes.

METHODS

The study was a longitudinal follow-up study of 15,464 participants with baseline normoglycemia. At baseline, conventional lipid parameters such as low-density lipoprotein cholesterol (LDL-C), triglyceride (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C) were measured/calculated, and unconventional lipid parameters such as non-HDL-C, remnant cholesterol (RC), LDL/HDL-C ratio, TG/HDL-C ratio, non-HDL/HDL-C ratio, TC/HDL-C ratio and RC/HDL-C ratio were calculated. Hazard ratio (HR) and 95% confidence interval (CI) were estimated by Cox proportional hazard regression adjusting for demographic and diabetes-related risk factors. The predictive value and threshold fluctuation intervals of baseline conventional and unconventional lipid parameters for future diabetes were evaluated by the time-dependent receiver operator characteristics (ROC) curve.

RESULTS

The incidence rate of diabetes was 3.93 per 1000 person-years during an average follow-up period of 6.13 years. In the baseline non-diabetic population, only TG and HDL-C among the conventional lipid parameters were associated with future diabetes risk, while all the unconventional lipid parameters except non-HDL-C were significantly associated with future diabetes risk. In contrast, unconventional lipid parameters reflected diabetes risk better than conventional lipid parameters, and RC/HDL-C ratio was the best lipid parameter to reflect the risk of diabetes (HR: 6.75, 95% CI 2.40-18.98). Sensitivity analysis further verified the robustness of this result. Also, time-dependent ROC curve analysis showed that RC, non-HDL/HDL-C ratio, and TC/HDL-C ratio were the best lipid parameters for predicting the risk of medium-and long-term diabetes.

CONCLUSIONS

Unconventional lipid parameters generally outperform conventional lipid parameters in assessing and predicting future diabetes risk. It is suggested that unconventional lipid parameters should also be routinely evaluated in clinical practice.