Patients with major depressive disorder exhibited sympathetic predominance compared with controls, an autonomic imbalance that was further exacerbated by 7 to 9 days of SSRI or SNRI treatment.
Observational (n=150)
Does short-term treatment with SSRI or SNRI antidepressants alter cardiac autonomic dysfunction in patients with major depressive disorder?
Major depressive disorder is associated with baseline cardiac autonomic dysfunction favoring sympathetic predominance, which is further worsened by short-term SNRI and SSRI therapy, highlighting potential arrhythmia risks in susceptible patients.
OBJECTIVE: To investigate cardiac autonomic dysfunction in patients with major depressive disorder (MDD). Research in this area has faced several limitations because of the heterogeneity of the disease, the influence of medication, and methodological shortcomings. METHODS: Participants were 75 patients suffering from an acute recurrent episode of MDD and 75 matched controls. All participants were assessed at baseline for linear and nonlinear parameters of heart rate variability, QT variability and baroreflex sensitivity. Participants with MDD were reassessed after 7 to 9 days of treatment with either a selective serotonin reuptake inhibitor (SSRI) or a serotonin and noradrenaline selective reuptake inhibitor (SNRI) antidepressant. RESULTS: In the initial examination, patients showed an overall shift of autonomic balance toward sympathetic predominance as compared with matched controls, with a decrease in parasympathetic parameters and baroreflex sensitivity, and an increase in sympathetically influenced QT variability. Overall, antidepressant treatment exacerbated this imbalance, with differential effects observed for SSRI and SNRI treatment. In contrast to autonomic dysfunction in other disorders, such as schizophrenia, autonomic dysfunction in MDD appeared to be independent of disease severity. CONCLUSIONS: Patients suffering from MDD show profound autonomic dysfunction, which is exacerbated by SNRI and to a lesser degree by SSRI treatment. This information could prove important when selecting antidepressant medication for patients at risk for cardiac arrhythmias.
Koschke et al. (2009) conducted an observational in Major depressive disorder (n=150). Major depressive disorder and SSRI/SNRI treatment vs. Matched controls was evaluated on Cardiac autonomic dysfunction (heart rate variability, QT variability, and baroreflex sensitivity). Patients with major depressive disorder exhibited sympathetic predominance compared with controls, an autonomic imbalance that was further exacerbated by 7 to 9 days of SSRI or SNRI treatment.