Associations between different heart rate variability ratios and cardiometabolic risk factors in young adults.

AIMS: To study the association of two different heart rate variability (HRV) ratios with cardiovascular disease (CVD) risk factors in young adults. METHOD: A total of 132 participants (89 women) were included in this cross-sectional study. We assessed their HRV and computed the low frequency-to-high frequency ratio (LF/HF) and, from the Poincaré plot, the ratio of the inverse of the longitudinal (SD2) to the transversal (SD1) axes ([1000/SD2]/SD1; sympathetic: parasympathetic [S:PS] ratio). From blood samples, we determined total cholesterol, high-density (HDL-C) and low-density lipoprotein-cholesterol, triglycerides, glucose, insulin, and the homeostatic model assessment of insulin resistance (HOMA) index. Multiple linear regression models were adjusted for age. RESULTS: Both, the LF/HF and the S:PS ratios, were positively associated with glucose metabolism markers (glucose, insulin, HOMA index), and negatively associated with HDL-C in women but not in men. CONCLUSION: We showed that the LF/HF and the S:PS are associated similarly with CVD risk factors in young women.