Effects Of Heart Rate Variability On Insulin Resistance, Perceived Stress And Lean Body Mass

Little information exists regarding the inter-relation of Heart Rate Variability (HRV), mental health, body composition and insulin sensitivity in the 17- to 18-year-old healthy population. PURPOSE: Identify the relationship between HRV and body composition, perceived stress and insulin sensitivity in students transitioning from high school to college. METHODS: 47 participants aged 17-18 years old participated in baseline testing during their senior year in high school. Insulin resistance was assessed through acquiring venous blood samples collected using standard aseptic technique following an overnight fast, using enzyme-linked immunosorbent assays and the homeostasis model assessment of insulin resistance (HOMA-IR). HOMA-IR was calculated as fasting insulin (μU/mL) * fasting glucose (mg/dL)/405. HRV was assessed using a 5-minute standard lead II ECG recording (BIOPAC Systems Inc., Goleta, CA, USA). Mental health was assessed using a 10-item Perceived Stress Scale (PSS-10). Body composition including ean Body Mass (LBM) was measured using GE-Lunar Prodigy DXA (GE Healthcare, Madison, WI, USA). Multivariable backwards linear stepwise regression was used to assess the effect of HRV on mental health, insulin resistance & lean body mass. RESULTS: See Table 1. R2 of models 1 and 2 were 0.186 (p = 0.071 and p = 0.033, respectively). LBM was statistically significant (R2 = 0.189, p = 0.02) however was not clinically significant due to small effect size. CONCLUSION: Insulin resistance, sex & perceived stress were not statistically significant in relation to HRV. Higher HRV in 17-18-year-olds has been observed suggesting better overall health. For every 0.5 kg change in lean body mass 0.01 change in HRV was observed; in a healthy population, the effect of lean body mass on HRV would be negligent. Table 1. - Relationship Between Insulin Resistance, Perceived Stress, Sex & Lean Body Mass Model Variable β P-value 1 Insulin Resistance 0.191 0.197 Perceived Stress 0.271 0.073 Sex -0.012 0.935 Lean Body Mass 0.342 0.021 2 Insulin Resistance 0.188 0.189 Perceived Stress 0.268 0.063 Lean Body Mass 0.341 0.02 National Heart, Lung, and Blood Institute of NIH under Award Number R15HL159650