Abstract

Background: Very few studies in Indian population have assessed cardiac autonomic functions in depressed patients. Extent of autonomic function derangement needs to be assessed along with any possibility of correlation of such dysfunction with severity of depressive disorder as conflicting results are published on this problem. Objectives: The current research work was, therefore, undertaken to study cardiac autonomic functions by heart rate variability (HRV) in major depressive disorder (MDD) without other comorbid conditions in comparison to healthy controls and to find out any correlation between altered HRV parameters and severity of depression.
Materials and Methods: Autonomic functions were assessed by studying time domain and frequency domain parameters in 60 patients of MDD without comorbid conditions and compared with 35 healthy controls. Association between severity of depression and HRV parameters was assessed in mild, moderate, and severe depression.
Results: Most of the time and frequency domain HRV parameters showed highly significant alterations as compared to control group (P values ranging from <0.01 to 0.0001). Statistically significant differences were noted in low, moderate, and high depression. Conclusion: HRV parameters are affected in MDD showing reduced variability with altered sympathovagal balance. Alteration in autonomic activity reflected in altered HRV parameters is associated with severity of depression suggesting possibility of HRV as a prognostic tool in the management of these patients.