Abstract
BACKGROUND AND AIMS: Depression is a common and debilitant mental health disorder that is very common among young adults of the age group of 18-25 years. There is evidence that autonomic nervous system dysfunction associated with depression may play an important role in cardiovascular disease among patients with depression. HRV that is used to assess ANS function is found to be altered in depression. Since the HRV findings associated with depression remain inconsistent, this study is aimed to find HRV changes associated with depression so that the use of HRV as a diagnostic tool for depression can be validated. METHODS: A total of 42 newly diagnosed patients of depression of the age group (18-26) years and 89 non-depressed volunteers matched for age, BMI and sex proportions were included in the study. Heart rate variability was recorded using five-minute stationary RR interval of Lead II by 4-channel Power Lab System (AD Instrument Ltd). HRV findings are summarized into Time-Domain parameters, Frequency-Domain parameters and Non-Linear parameters. RESULT: All HRV parameters are significantly reduced and the LF/HF ratio is significantly raised (P < 0.05) in the group of depressive patients when compared to the group of healthy controls. The reduction of HRV parameters (SDRR, RMSSD, Total Power, SD1 and SD2) in the group of patients with depression is found to be highly significant (P < 0.0001). CONCLUSION: The findings of our study suggest that depression may be associated with alterations in ANS activities, which contribute to an increased risk of cardiovascular disease. Thus, HRV can serve as a potential bio-marker for depression.