Effect of Body Mass Index on Cardiac Autonomic Functional Status in Healthy Young Adults

Abstract

Introduction: Autonomic nervous system (ANS) is involved in energy metabolism and regulation of the cardiovascular system. Autonomic dysfunction has been suggested to occur in obese individuals in both adults and children but a comprehensive study of the autonomic status in young adults is scant. So aim of the study was to evaluate and compare cardiovascular autonomic functions in young adults on the basis of BMI. Material and methods: 150 healthy young students of MMU aged 18-25 years, divided into four groups based on BMI as per Asian criteria (underweight, normal weight, overweight and obese). Various autonomic function tests done were Lying to Standing test, Valsalva manoeuvre, Hand grip test (HGT) and Cold pressor test (CPT). Results:The mean baseline SBP and DBP were significantly higher in obese subjects followed by overweight, normal weight and under weight. No parasympathetic alteration between different BMI groups was seen. Mean values of resting SBP and DBP were significantly higher and blood pressure response to HGT and CPT was significantly lower in obese as compared to normal weight subjects. Conclusion:Our study revealed an altered autonomic function in the form of impaired sympathetic activity with no parasympathetic modulation in obese young adults. So weight reduction and moderate intensity aerobic exercise programmes should be incorporated into daily living, which may delay or prevent the onset of hypertension.