IMPACT OF BODY MASS INDEX ON SYMPATHOVAGAL BALANCE IN NORMOTENSIVE ADULTS

Background: Obesity is one of the important risk factor for hypertension. Hence the body mass index has a paramount influence on the sympathovagal balance of the cardiac autonomic activity that has a control over the heartrate and blood pressure. Disruption in the balance results in development of hypertension. The sympathovagal balance is represented as the LF:HF ratio in the spectral analysis of heart rate variability. Hence the present study aims at evaluating the effect of body mass index on sympathovagal balance in adults with normal blood pressure. This cross Materials and Methods: sectional study was carried out on 60 normotensive subjects between the age group of 20 to 50 years. They are divided into two groups based on BMI according to WHO guidelines. Group I consists of 30 normotensive subjects with normal BMI of 18.5 to 24.9 kg/m2 and Group II included 30 normotensive subjects with BMI above 25 kg/m2. The two groups were subjected to spectral analysis of heart rate variability test and the LF:HF ratio was determined and correlated with BMI. The analysis by Pearson correlation showed a statistically significant positive correlation be Results: tween the LF:HF ratio and BMI in subjects with higher body mass index. In subjects with higher BMI, there is Conclusion: high LF:HF ratio indicating the sympathovagal imbalance with sympathetic overactivity and parasympathetic withdrawal than in subjects with normal BMI and thereby it indicates the risk of developing hypertension in the future. This mandates the need for early intervention to prevent cardiovascular risks.