Effect of obesity on autonomic functions of Heart among healthy volunteers at a teaching Institute

BACKGROUND: Obesity usually results from an imbalance between energy intake and energy expenditure, that is, energy homeostasis, which is controlled by the autonomic nervous system. This imbalance results from multifaceted interactions of genetic, physiological, behavioral, environmental, endocrine, nervous, metabolic factors, which lead to hemodynamic and metabolic alteration. OBJECTIVE: To study the effect of obesity on the autonomic functions of the heart. METHODS: An observational analytical study was carried out among 100 subjects. All healthy volunteers of 30–50 years were included. The subjects were grouped into two categories of body mass index (BMI): 30–39.99 kg/m(2) as Obese group and BMI: 18.50–24.99 kg/m(2) as Non -Obese group. Out of 100 subjects, 50 were obese and 50 were non-obese. The interview was taken. General physical examination and anthropometric measurements were recorded. The assessment of various cardiac autonomic function tests was carried out. RESULTS: Both groups were comparable for age and sex (P = 0.754). The resting heart rate, SBP, and DBP in the obese group were significantly higher compared to the non-obese group (P < 0.05). All values of autonomic function tests in the non-obese group were significantly higher compared to the obese group (P < 0.05) except for the Standing to lying ratio (P > 0.05). The values of SBP and DBP increased significantly in the non-obese people after the isometric handgrip test and cold press test compared to the obese people (P < 0.05). CONCLUSION: We conclude that the resting HR, SBP, and DBP were higher in obese people. However, after applying autonomic function tests, non-obese people respond better to these tests compared to obese people in the form of an increase in these parameters. Obesity is, thus, found to affect the autonomic function tests