A Comparative Study of Heart Rate Variability During Acute Mental Stress in Obese Priya S.A1, Rajalakshmi R.2,*, Siddanagoudar Savitri P3, Nanjundaiah N.4 1Assistant Professor, Department of Physiology, JSS MedicaL College, JSSAHE&R, Mysuru 2Professor and HOD, Department of Physiology, JSS Medical College, JSSAHE&R, Mysuru 3Associate Professor, Department of Physiology, SDM College of Medical Sciences & Hospital, Dharwad 4Senior Resident, Department of Surgery, Kodagu Institute of Medical Sciences & Hospital, Madikeri, Karnataka *Corresponding Author: Dr. Rajalakshmi R. Professor and HOD, Department of Physiology, JSS Medical College, JSSAHE&R, Mysuru. Karnataka
Online published on 21 November, 2019. Abstract Background Under normal circumstances, reaction to mental stress would be increase in heart rate. Fluctuation in the time intervals in the successive heart beat is assessed by Heart rate variability (HRV). Analysis of heart rate variability during acute mental stress throws light on autonomic regulation. Since Obesity is morbid condition leading to cardiovascular disorder, we intend to study the heart rate variability during acute mental stress in obese individuals. Method and results This is a Case-control study conducted on 60 male adults (30 obese and 30 non obese) between 18 to24 years. All the subjects underwent mental arithmetic stress task for 5minutes. Then they were investigated for HRV parameters before mental stress task and during mental stress by recording ECG in lead II. Results In the time domain variables of HRV, mean heart rate showed a statistical significant increase (p < 0.001) in both obese and non obese individuals, while RMSSD and SDNN showed a statistical significant (p< 0.001) decrease in obese individuals and non obese individuals did not show statistical significant change during the mental stress task. During mental stress task there was decrease in all the components of frequency domain of HRV in obese with decrease in LFnu being statistically significant (p= 0.002). Whereas in non obese individuals, there was statistical increase in LF nu (p < 0.001) and LF/HF ratio (p < 0.05). Conclusion To conclude, this study indicates that the short-term mental stress led to changes in autonomic regulation both in obese and non obese group, but there was autonomic dysregulation in obese group in the form of decrease in parasympathetic activity. Top Keywords Acute Mental Stress, Obesity, Heart rate variability. Top |