Heart rate variability as a method of autonomic nervous system assessment in selected psychiatric disorders

Purpose
Analysis of heart rate variability (HRV) based on ECG is a non-invasive method which assesses the activity of both the sympathetic and the parasympathetic part of autonomic nervous system. HRV measurement describes time differences between consecutive heartbeats – intervals between the R waves of the QRS complex. The aim of the article is to present results of research on HRV in selected mental disorders.

Views
People with mental disorders have reduced HRV, especially components dependent on parasympathetic activity, and more often than healthy subjects develop cardiovascular diseases. Moreover, drugs psychiatric drugs can also have negative influence on HRV. Reduction of HRV, dependent on sympathetic predominance, has been described in numerous mental disorders – schizophrenia, affective and anxiety disorders, insomnia. Among the antipsychotics, the least favorable for heart is the effect of clozapine, treatment with amisulpride and risperidone seems safe. Antidepressants also have a different cardiological safety profile. The least beneficial is the action of tricyclic antidepressants. Venlafaxine and mirtazapine also lower HRV, while SSRIs, including paroxetine which has the largest in this group cholinolytic action, seem to be safe. In the case of HRV-reducing drugs it is advisable to use the lowest effective dose, as the HRV parameters are reduced with increasing the dose of the drug.

Conclusions
HRV analysis is reliable and technically easy to perform. The results of presented studies indicate that HRV assessment may be widely used in psychiatry as a biological marker of an autonomic excitation and to evaluate cardiological safety of drugs.