Triglyceride-glucose index and lipid ratios in women with and without polycystic ovary syndrome: a systematic review and meta-analysis

Background: The pathophysiology of polycystic ovary syndrome (PCOS) is complex and heterogeneous. This systematic review and meta-analysis aimed to determine the triglyceride-glucose index and lipid ratios in women with and without PCOS. Methods: Literature searches were performed in PubMed, Scopus, Web of Science, Scielo, and Embase for studies reporting the triglyceride-glucose index and total cholesterol/high-density lipoprotein (HDL)-cholesterol, triglyceride/HDL-cholesterol, and low-density lipoprotein (LDL)-cholesterol/HDL-cholesterol ratios. Results are reported as standardized mean differences (SMDs) along with their 95% confidence intervals (CIs). Results: The search identified 61 observational studies, including case-control (n = 37), cohort (n = 2), and cross-sectional (n = 22) studies reporting results of interest according to different PCOS diagnosis criteria. Compared with the control group, the PCOS group presented increased circulating triglyceride-glucose index (n = 9 studies, SMD, 0.41; 95% CI, 0.08-0.74) and total cholesterol/HDL-cholesterol (n = 35 studies, SMD, 1.70; 95% CI, 0.69-2.70), triglyceride/HDL-cholesterol (n = 31 studies; SMD, 0.81; 95% CI, 0.43-1.19), and LDL-cholesterol/HDL-cholesterol (n = 25 studies, SMD, 2.40; 95% CI, 0.45-4.35) ratios. Statistical heterogeneity values were very high (I-2 > 90%). The PCOS group displayed significantly higher body mass index and homeostatic model assessment of insulin resistance. The PCOS group was younger than the control group and had a higher total cholesterol/HDL-cholesterol ratio, and other lipid variables were comparable in all groups. Conclusion: Patients with PCOS show significantly higher triglyceride-glucose index and total cholesterol/HDL-cholesterol, triglyceride/HDL-cholesterol, and LDL-cholesterol/HDL-cholesterol ratios than those without the syndrome.