Heart rate variability and heart rate in a sample of medicated and unmedicated adolescents with obsessive-compulsive disorder

Association of Neuroticism and Conscientiousness with Sympathovagal and Heart Rate Variability Indices in Medical Undergraduates

Objective: Heart rate variability (HRV) is widely used to characterise cardiac autonomic regulation, but the extent to which specific personality traits relate to short-term HRV indices in medical students remains uncertain. This study examined whether neuroticism and conscientiousness were associated with frequency-domain and time-domain HRV measures in first-year medical undergraduates. Methods: In this cross-sectional study, 100 first-year MBBS students aged 18-24 y underwent 5-minute resting ECG recording in the supine position after standard pre-recording stabilisation. HRV analysis was performed in Kubios HRV Scientific to derive SDNN, RMSSD, pNN50, low-frequency (LF) power, high-frequency (HF) power, and the LF/HF ratio. Personality was assessed with the Big Five Inventory, with primary analyses focused on neuroticism and conscientiousness. Pearson correlations and multivariable linear regression were used. Results: Neuroticism correlated positively with LF power (r=0.42, p<0.001) and LF/HF ratio (r=0.46, p<0.001), and negatively with pNN50 (r=-0.40, p<0.001) and HF power (r=-0.39, p<0.001). Conscientiousness showed the reverse pattern, with positive correlations for pNN50 (r=0.27, p=0.007) and HF power (r=0.27, p=0.007), and negative correlations for LF power (r=-0.29, p=0.004) and LF/HF ratio (r=-0.33, p=0.001). Neither trait was significantly associated with SDNN or RMSSD. In multivariable models, neuroticism remained an independent predictor of LF/HF ratio (B=0.037, p=0.007), pNN50 (B=-0.397, p=0.017), HF power (B=-11.965, p=0.017), and LF power (B=8.317, p=0.009), whereas the models for SDNN and RMSSD were not significant. Conclusion: In this cohort, neuroticism and conscientiousness were associated mainly with vagally weighted and spectral HRV indices rather than with global short-term variability. These findings support a cautious interpretation in which personality traits relate to resting autonomic patterning in medical students, while not implying causality or direct mechanistic inference.

Heart rate variability as a biomarker of autonomic (re)activity and fatigue in multiple sclerosis.

Fatigue is a debilitating symptom in multiple sclerosis (MS) associated with autonomic nervous system (ANS) dysfunction. Heart rate variability (HRV) provides a non-invasive measure of ANS function; yet the relative sensitivity of linear and nonlinear HRV parameters in capturing specific ANS (dys)function remains unclear. This study investigated the factorial structure of HRV parameters, their response to biopsychological interventions, and their relationship with MS-related fatigue. Data from two clinical trials (N = 78) were pooled. Exploratory factor analysis (EFA) was applied to time-domain, frequency-domain, and nonlinear HRV parameters. Repeated-measures ANOVAs examined the effects of self-alert training (SAT; activating), deep breathing (DB; relaxing), and progressive muscle relaxation (PMR; intermediate) on HRV, controlling for age, depression, and disability. Subsequent regression analyses investigated whether HRV changes during a vigilance task predicted MS-related fatigue. EFA revealed two factors, likely reflecting parasympathetic (PNS) or sympathetic (SNS) activity. SAT decreased HRV parameters loaded onto both factors, DB increased parameters related to the factor interpreted as mainly reflecting SNS activity, and PMR affected both factors. Reduced SDNN change during the vigilance task predicted higher trait fatigue, whereas state fatigue was not associated with HRV. HRV offers the potential to monitor PNS-SNS-related activity during psychological interventions and to measure reduced autonomic adaptability in MS-related trait fatigue.

Detecting effects of yoga therapy on heart rate variability and autonomic nervous system functioning in adults after cancer treatment: results from a study using single-subject experimental methods

Cancer is a source of physiological and psychological stress. Heart rate variability (HRV) is a measure of autonomic reactivity to physiological and psychological stress. For an initial proof-of-concept, we investigated the effects of a yoga therapy (YT) intervention on HRV metrics and self-reported autonomic nervous system (ANS) functioning using single-subject experimental methods. Data from 20 adults (Mage (years) = 55.7 [SD = 8.6], 85% female, Myears from diagnosis = 2.8 [SD = 3.5]) were analyzed. Participants received an initial 90-min 1:1 YT session followed by 6 weekly 60-min small group YT sessions. Hexoskin Smart Shirts captured single lead electrocardiographic data suitable for HRV analysis, and questionnaires were used to assess self-reported state and trait ANS functioning. Data collected prior to (weeks − 6, −3, and 0a), during (immediately after the 1:1 YT session [week 0b] and before the first group session [week 1]), and after (weeks 7 and 12) the YT intervention were analyzed. Hierarchical linear modeling (HLM) was used to estimate average baseline levels (intercept), linear slopes (time), YT initiation effect on levels (phase), and YT intervention effect on linear slopes (time-by-phase) for each outcome. HLM yielded mixed results. Significant (p < 0.05) time, phase, and time-by-phase effects for state ANS, coefficient of variation and high frequency power, time-by-phase effect for trait ANS, and time and phase effects for sample entropy were observed. No significant effects were observed for remaining analyzed HRV metrics. Though mixed, results establish an initial proof-of-concept required to justify larger studies investigating the effects of YT on HRV and self-reported ANS functioning in adults after cancer treatment. ISRCTN registry. ISRCTN64763228. December 12, 2021. This study was retrospectively registered. https://www.isrctn.com/ISRCTN64763228.

Cardiovascular autonomic dysfunction in Morvan syndrome: A comparative study of heart rate variability and cardiovascular autonomic reflex tests.

Findings support the value of routine HRV and Ewing's battery assessment in Morvan syndrome for early detection of cardiovascular autonomic involvement and improved clinical monitoring.

Modulation of heart rate and heart rate variability during animal-assisted treatment of patients in a minimally conscious state: A randomized controlled crossover study.

BACKGROUND Animal-assisted treatment (AATx) is a promising and increasingly used approach in neurorehabilitation, yet its psychophysiological effects remain largely unexplored. Patients in a minimally conscious state (MCS) show severely altered consciousness with minimal but definite behavioral signs of awareness. Because behavioral assessment in this population is limited, psychophysiological measures such as heart rate (HR) and heart rate variability (HRV) may offer valuable insights into autonomic regulation during therapy. AIM The present study investigated whether AATx influences HR and HRV compared to treatment as usual (TAU). METHODS A randomized controlled crossover design with repeated measures was conducted. HR and HRV data were recorded using an Empatica E4 wristband, and linear mixed-effects models were fitted for each outcome variable. The analytic sample included twenty-one patients with MCS who completed at least one of the four sessions. RESULTS We found a significant decrease in mean HR (estimate = -12.75, p =.041) and a significant increase in the standard deviation of normal-to-normal intervals (SDNN) (estimate = 15.76, p =.020) during AATx compared to TAU from the pretreatment to the posttreatment phase, indicating enhanced parasympathetic activation and greater autonomic flexibility. Other HRV parameters revealed no significant effects of AATx, though trends were consistent with the hypotheses. CONCLUSIONS These findings provide preliminary physiological evidence that AATx can modulate autonomic activity in MCS patients. Despite limitations related to sample size and recording quality, the results highlight the potential of AATx as an emotionally engaging intervention in early neurorehabilitation.

From Subjective to Objective: The Bedside Value of HRV in AssessingChronic Pain Complicated by Emotionaland Sleep Issues.