title: A blunted sympathetic and accentuated parasympathetic response to postural change in subjects with depressive disorders.
abstract: BACKGROUND
  In recent years, the bi-directional relationship between depression and ANS dysfunction has received considerable attention, but findings remain inconclusive. In this study, we aimed to examine the spectral HRV response to postural change in subjects with depressive disorders and in healthy controls, in order to gain insight into the characteristics of autonomic nervous system (ANS) response to postural change in subjects with depressive disorders.
  
  
  METHODS
  We compared HRV response to postural change between subjects with depressive disorders and healthy controls aged 20-37 years. Depression severity was assessed by the self-reported Beck Depression Inventory-II (BDI-II). Spectral HRV was analyzed at two moments: 10 min seated rest and 10 min at standing position, with spontaneous breathing.
  
  
  RESULTS
  No significant differences existed in the resting spectral HRV indices between subjects with depressive disorders and controls, however, following postural change, the increasing level of LF and LF/HF was lower and the decreasing level of HF power was higher, in the individuals with depression than that in healthy subjects. The differences in the LF power, HF power and the LF/HF ratio between seated rest before standing up and after postural change were found negatively correlated with depression severity.
  
  
  CONCLUSIONS
  We found a blunted sympathetic and accentuated parasympathetic response to postural change in subjects with depressive disorder, suggesting that the autonomic impairment and early ANS dysfunction may exist among depressed individuals. These findings indicated that spectral analysis of HRV associated with postural change may be a more sensitive method than resting HRV analysis for detecting ANS dysfunction in depressive disorders.
  
  
  CONCLUSIONS
  Further studies are needed to expand the sample size and to clarify the mechanisms responsible for the autonomic dysfunction observed in individuals with depressive disorders.
authors: Department of Epidemiology, School of Public Health and Tropical Medicine, Southern Medical University, Guangdong Province 510515, China. Electronic address: 729271960@qq.com.
authors: Xiao-ling
authors: XL
authors: Jiang
authors: Department of Physiology, School of Basic Medical Sciences, Southern Medical University, Guangdong Province 510515, China.
authors: Zheng-gang
authors: ZG
authors: Zhang
authors: Department of Epidemiology, School of Public Health and Tropical Medicine, Southern Medical University, Guangdong Province 510515, China.
authors: Yuanyuan
authors: Y
authors: Chen
authors: Department of Epidemiology, School of Public Health and Tropical Medicine, Southern Medical University, Guangdong Province 510515, China.
authors: Cui-Ping
authors: CP
authors: Ye
authors: Department of Epidemiology, School of Public Health and Tropical Medicine, Southern Medical University, Guangdong Province 510515, China.
authors: Ying
authors: Y
authors: Lei
authors: Department of Epidemiology, School of Public Health and Tropical Medicine, Southern Medical University, Guangdong Province 510515, China.
authors: Lei
authors: L
authors: Wu
authors: Department of Epidemiology, School of Public Health and Tropical Medicine, Southern Medical University, Guangdong Province 510515, China.
authors: Ying
authors: Y
authors: Zhang
authors: Department of Physiology, School of Basic Medical Sciences, Southern Medical University, Guangdong Province 510515, China. Electronic address: 1971994747@qq.com.
authors: Zhong-ju
authors: ZJ
authors: Xiao
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D003866:Depressive Disorder / Q000503:physiopathology*; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D010275:Parasympathetic Nervous System / Q000503:physiopathology*; D011187:Posture / Q000502:physiology*; D011569:Psychiatric Status Rating Scales; D013564:Sympathetic Nervous System / Q000503:physiopathology*; D055815:Young Adult
keywords: Depressive; Heart rate variability; Postural change