Effect of Yoga on Nonlinear Dynamics of Heart Rate in Prediabetic Subjects

Introduction: Pre-diabetes represents the initial stage of type 2 diabetic disease developments. Prediabetes disease progression to overt type 2 diabetes occurs when pancreatic beta cells cannot produce insulin to overcome insulin resistance, resulting in further hyperglycaemia. Prediabetic patients have higher risk for Cardiovascular Diseases (CVDs) which further increases the rate of mortality. Lifestyle interventions such as yoga can prove to be a beneficial non pharmacologic intervention in preventing progression of prediabetes to type 2 diabetes. Aim: Present study highlights the importance of short term intervention i.e., yoga on Heart Rate Variability (HRV) in prediabetic subjects and its use as a tool for homeostasis of Autonomic Nervous System (ANS) and primary prevention of diabetes. Materials and Methods: This was an interventional study conducted on adults aged 30 to 50 years for analysis of frequency domain parameters i.e., Low Frequency (LF), High Frequency (HF), ratio of low frequency to high frequency of HRV. A total 102 prediabetic subjects were recruited from OPD of Jaipuria Hospital. These were divided into two groups A and B. Group A (n=51) were given intervention of set of yogic exercises and Group B (n=51) did not perform any yoga session. Statistical analysis was done by student's paired t test for intragroup comparison before applying this test the Smirnov-Kolmogorov test was conducted to confirm the normality of each parameter. Results: Yoga intervention resulted in a significant decline in LF component and increase in HF component and LF/HF (Low Frequency/High Frequency) ratio shift sympathetic to parasympathetic dominance (p-value<0.001) in study group relative to the control group. Conclusion: Short term yoga intervention is helpful in shifting of ANS towards the parasympathetic dominance which is assessed by frequency domain of HRV in prediabetes subjects. This preliminary study indicates that a yogic exercise change mind, body balance that facilitates autonomic balance for adults at high risk for type 2 diabetes. In addition, yoga holds promise as an approach to reducing cardiometabolic risk factors and increases exercise efficacy in prediabetics performing yoga.