Autonomic Dysfunction in Unaffected First-Degree Relatives of Patients Suffering From Schizophrenia

Abstract

Recent studies revealed cardiac autonomic dysfunction in patients with acute schizophrenia, which appears to be mainly related to reduced vagal and increased sympathetic modulation. To understand the significance of cardiac autonomic function in patients with schizophrenia, we extended these studies to relatives of patients. In this study, we assessed cardiac autonomic modulation in healthy first-degree relatives of patients with schizophrenia (n = 36) to investigate a putative genetic influence. Data were compared with control subjects matched for age, gender, and physical activity as well as to patients suffering from schizophrenia. First-degree relatives showed an attenuated, yet identical pattern in autonomic dysfunction as patients with decreased vagal modulation of heart rate, decreased baroreflex sensitivity, but no difference in blood pressure variability could be detected. The patients' relatives also showed a similar pattern in regards to QT variability. In addition, the subgroup comparison of offspring vs. siblings showed a significant difference in heart rate variability suggesting a higher degree of heritability in offspring. In conclusion, the pattern of autonomic dysfunction seen in patients and relatives might indicate underlying disease-inherent genetic vulnerability, especially because autonomic parameters are heritable. In addition, these findings may be of value to identify the high-risk group of patients' relatives in regards to serious cardiovascular events so that early preventive measures can be taken.

Autonomy of Autonomic Dysfunction in Major Depression

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Individual differences in cardiac vagal tone are associated with differential neural responses to facial expressions at different spatial frequencies: An ERP and sLORETA study

“…The present study indicates that people with low resting HRV show heightened activities in similar brain areas for neutral face stimuli. There is extensive evidence suggesting that reduced HRV was associated with serious psychiatric illness, such as bipolar disorder and schizophrenia (Bär et al, 2009;Castro et al, 2008). Severity of psychotic symptoms of schizophrenia was associated with cardiac autonomic disturbance (Bär et al, 2008).…”

High-resolution joint symbolic analysis to enhance classification of the cardiorespiratory system in patients with schizophrenia and their relatives

“…In addition to these factors, the dysregulation of the autonomic nervous system (ANS) during acute psychosis has become evident for patients with schizophrenia in studies carrying out heart rate variability (HRV) analysis. Studies applying HRV analyses found reduced vagal and increased sympathetic modulation, indicating a cardiac autonomic dysregulation in patients with schizophrenia and partly in their healthy first-degree relatives [6][7][8][9][10][11][12][13]. The pattern of autonomic dysfunction seen in patients and their relatives might indicate underlying diseaseinherent genetic vulnerability, especially as it was shown by Busjahn et al [14] that a genetic dependency of autonomic parameters (HRV) exists.…”