Heart rate variability is a trait marker of major depressive disorder: evidence from the sertraline vs. electric current therapy to treat depression clinical study

Abstract

Decreased heart rate variability (HRV) is a cardiovascular predictor of mortality. Recent debate has focused on whether reductions in HRV in major depressive disorder (MDD) are a consequence of the disorder or a consequence of pharmacotherapy. Here we report on the impact of transcranial direct current stimulation (tDCS), a non-pharmacological intervention, vs. sertraline to further investigate this issue. The employed design was a double-blind, randomized, factorial, placebo-controlled trial. One hundred and eighteen moderate-to-severe, medication-free, low-cardiovascular risk depressed patients were recruited for this study and allocated to either active/sham tDCS (10 consecutive sessions plus two extra sessions every other week) or placebo/sertraline (50 mg/d) for 6 wk. Patients were age and gender-matched to healthy controls from a concurrent cohort study [the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil)]. The impact of disorder, treatment and clinical response on HRV (root mean square of successive differences and high frequency) was examined. Our findings confirmed that patients displayed decreased HRV relative to controls. Furthermore, HRV scores did not change following treatment with either a non-pharmacological (tDCS) or pharmacological (sertraline) intervention, nor did HRV increase with clinical response to treatment. Based on these findings, we discuss whether reduced HRV is a trait-marker for MDD, which may predispose patients to a host of conditions and disease even after response to treatment. Our findings have important implications for our understanding of depression pathophysiology and the relationship between MDD, cardiovascular disorders and mortality.

Neuropathological and neuromorphometric abnormalities in bipolar disorder: View from the medial prefrontal cortical network

“…Thus neuropathological changes in the mPFC may result in the reduction in parasympatheticto-sympathetic tone observed in a proportion of mood disorder patients, potentially explaining the elevated risk for ventricular tachycardia and myocardial infarction in depressed patients with cardiovascular disease (Carney et al, 2005). The reduction in parasympathetic and vagal tone observed in depressed and manic subjects (Brunoni et al, 2013;Henry et al, 2010;Kemp et al, 2012;Udupa et al, 2007) may additionally result in abnormal autonomic responses, and by implication abnormal affective responses to both internal or external stimuli. For instance, Lane et al (2009) reported that the vagally-mediated component of heart rate variability correlated with changes in regional cerebral blood flow (rCBF) in the mPFC during the induction of happiness, sadness, and disgust.…”

Comparison of Heart Rate Variability Between Patients With Major Depressive Disorder and Normal Subjects

“…However, many factors that influence on depression have been associated with the decreased cardiac vagal control. It may be a trait marker for MDD [17] which can be used for evaluating and classifying the severity of symptoms in these patients. This study aimed to compare heart rate variability between patients with the major depressive disorder and normal subjects.…”

Plasma levels of soluble TNF receptors 1 and 2 after tDCS and sertraline treatment in major depression: Results from the SELECT-TDCS trial

“…In previous studies, we found that the blood levels of several cytokines (IL-2, IL-4, IL-6, IL-10, IL-17a, IFN-γ) decreased after tDCS treatment, but also in the placebo arm (Brunoni et al, 2014c) and that heart rate variability did not change after tDCS treatment, regardless of treatment response (Brunoni et al, 2013a),. Thus, neither the HPA axis nor the autonomous nervous system are majorly implied in the antidepressant mechanisms of tDCS, at least during the MDD acute phase.…”