title: Heart rate variability responses to standing are attenuated in drug naive depressed patients.
abstract: Depression has been linked to altered cardiac autonomic regulation. Previous studies have been inconsistent in terms of measurement of heart rate variability (HRV), selection of depressed patients with cardiac disorders and not controlling for co-morbid conditions such as substance use and anxiety disorders. The objective of this study is to compare the effect of posture on spectral measures of HRV in drug naive healthy patients with major depression with age and gender matched healthy controls. Spectral measures of HRV in supine position and with active standing were obtained (using Task force recommendations). Repeated measure ANOVA revealed an attenuated response in HRV parameters (HF normalized units & LH/HF ratio) to active standing in depressed subjects compared to healthy controls. We conclude that there is an impaired parasympathetic modulation in response to physiological maneuver (orthostatic challenge) in drug naive subjects with major depression (co-morbid medical or psychiatric conditions) compared to healthy controls.
authors.affiliation: Department of Psychiatry, St. John's Medical College and Hospital, St. John's National Academy of Health Sciences, Sarjapur Road, Bangalore--560 034.
authors.forename: Johnson
authors.initials: J
authors.lastname: Pradeep
authors.forename: Sucharita
authors.initials: S
authors.lastname: Sambashivaiah
authors.forename: Tinku
authors.initials: T
authors.lastname: Thomas
authors.forename: Rajiv
authors.initials: R
authors.lastname: Radhakrishnan
authors.forename: Mario
authors.initials: M
authors.lastname: Vaz
authors.forename: Krishnamachari
authors.initials: K
authors.lastname: Srinivasan
mesh_terms: D000328:Adult; D001341:Autonomic Nervous System / Q000503:physiopathology*; D016022:Case-Control Studies; D003865:Major Depressive Disorder / Q000503:physiopathology*; D004562:Electrocardiography / Q000379:methods; D005260:Female; D006321:Heart / Q000503:physiopathology*; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D011187:Posture / Q000502:physiology*