NEUROPSYCHOLOGICAL FEATURES AS MEDIATORS BETWEEN PSYCHOPATHOLOGIES AND HEART RATE VARIABILITY: THE SEX DEFFERENCES

Abstract Background Heart rate variability (HRV), as an index of parasympathetic activity, has been reported to be lower in individuals with common mental disorders (depression, anxiety, and somatic symptoms) than in healthy individuals in previous studies. Several meta-analyses have supported this result, but the effect sizes of the differences between patients and healthy individuals are mostly low to moderate, making it difficult for small sample studies to demonstrate between-group differences. Therefore, the mechanisms underlying the link between the psychopathologies of common mental disorders and HRV require further investigation. In recent years, the theory of the frontal-vagal network has gained increasing attention. Furthermore, the relationship between psychopathologies and HRV has been reported to differ between sexes. Aims & Objectives Under the hypothesis that disorder status affects cognitive function, we examined whether neuropsychological features can be mediators between psychopathologies and HRV and possible sex differences. Method We recruited 359 individuals with and without common mental disorders. Questionnaires were used to measure their psychopathologies. Eight tests from the Cambridge Neuropsychological Test Automated Battery were selected to measure neuropsychological functions. Resting-state HRV measurements were obtained for 5 min. The associations among these constructs were analyzed using multiple linear regression analysis and structural equation modelling. Results When psychopathologies and neuropsychological features were simultaneously included as independent variables, most psychopathologies did not exhibit significant associations with HRV. Among women, Reaction Time (RTI, a task of psychomotor speed) indicator mediated the relationship between depression and low-frequency power (LF); Emotion Recognition Task (ERT, a task of emotional regulation) indicator mediated the relationship between health anxiety and high-frequency power (HF). Among men, Intra-Extra Dimensional Set Shift (IED, a task of shifting) indicator mediated the relationship between depression and LF; Match to Sample Visual Search (MTS, a task of selective attention) indicator mediated the relationship between health cognition and HF. The depression-RTI-LF pathway in women tended to lower HRV; whereas health anxiety-ERT-HF in women, depression-IED-LF and health cognition-MTS-HF in men tended to increase HRV. Discussion & Conclusion Our findings support the notion that neuropsychological features mediate the relationship between psychopathologies and HRV, and that sex differences exist.