The Mediating Effect of Triglyceride/High Density Lipoprotein Cholesterol Ratio on Inflammatory Markers and the Metabolic Syndrome in the Postmenopausal Women

Abstract

Session presented on Saturday, July 25, 2015: Purpose: The metabolic syndrome (MS) has relatively high prevalence in postmenopausal women. The high incidence of MS in menopausal is corroborated by numerous factors including central obesity, dyslipidemia, decreased glucose tolerance, and increased pro-inflammatory. However, few studies have investigated the most significant risk components of MS especially in postmenopausal women. This study was designed to explore the associations among inflammatory parameter (mainly the interleukin-6, IL-6), insulin resistance, triglyceride/high density lipoprotein cholesterol (TG/HDL-C) ratio and MS in postmenopausal women; and (2) to identify the most prominent risk indicators in the development of MS among postmenopausal women. Methods: A cross-sectional study was performed and the protocol was approved by the ethics committee of the university-based medical center in NortheRNaiwan. Postmenopausal women were recruited if aged between 45 and 70 years and were not taking medications including lipid-lowering agents, non-steroid anti-inflammatory drugs or hormone therapy. All analyses were performed with SPSS version 19 for windows. Hierarchical multiple logistic regressions were used to analyze the effect of related variables including IL-6, insulin resistance, and TG/HDL-C ratio on the MS. A forward hierarchical procedure was applied for the model selection. The bootstrap resampling procedure was used to test the significance of the specific effects of measured variables on the MS. Results: Eighty-nine women (mean age: 56.70+/-6.37 years) completed this study. MS was diagnosed in 58 (65%) women according to the criterion defined by the international Diabetes Federation. The MS was significantly positive correlated with age, BMI, insulin resistance, TG/HDL-C ratio and IL-6 levels (r=0.24, 0.24, 0.31, 0.43 and 0.30, all p <0.05, respectively). Results from the hierarchical multiple logistic regression models showed that only TG/HDL-C ratio (after controlling for age covariance) was significantly associated with the MS in postmenopausal women ( ?=1.15, p< 0.01). Results from the bootstrap resampling procedure further revealed that IL-6 levels had a significant indirect effect on MS, with TG/HDL-C ratio carrying the influence of IL-6 on the dependent variable of MS. Conclusion: Result of this study support the important role of IL-6 and TG/HDL-C ratio in MS among postmenopausal women. We also found the significant mediating effect of TG/HDL-C ratio on IL-6 in the development of MS. The intervention to change the TG/HDL-C ratio would be an important primary and secondary prevention for health promotion in postmenopausal women.