Heart Rate Variability Variables Research Articles

Correlation between Heart Rate Variability and Disease Severity in Obstructive Sleep Apnea

Objective: This study aimed to investigate the variations in Heart Rate Variability (HRV) among individuals with Obstructive Sleep Apnea (OSA) and to explore the relationship between HRV, respiratory parameters, and disease severity. Methods: This prospective study included sixty participants diagnosed with OSA. Polysomnography (PSG) was utilized to assess HRV parameters, including time-domain and frequency-domain measures. Participants were categorized based on the severity of OSA, and data on hemoglobin (HGB), C-reactive protein (CRP), triglyceride (TG) levels, and nocturnal oxygen desaturation (NOD) were collected. Statistical analyses were performed to evaluate the correlations between HRV, respiratory parameters, and disease severity. Results: Among the participants, 23 (38%) had severe OSA, while 17 (28%) were habitual snorers (HS). Hemoglobin, C-reactive protein, and triglyceride levels were significantly higher in patients with severe OSA and NOD compared to HS individuals (p=0.002). Increased Epworth Sleepiness Scale (ESS) scores were associated with higher heart rates during sleep in severe OSA patients compared to HS individuals. NOD (+) patients exhibited statistically higher heart rates during sleep compared to NOD (-) patients (p=0.008). Individuals with an apnea/hypopnea index (AHI) >30, NOD (+), and the lowest SpO2 percentage overnight had significantly lower HRV compared to HS and NOD (-) individuals. Conclusions: In addition to AHI, NOD and the lowest overnight SpO2 are significant markers of elevated cardiovascular risk and are useful for assessing HRV. These findings suggest that cardiovascular risks in OSA patients are heightened both during sleep and wakefulness. Therefore, individuals with severe symptoms, especially those with excessive daytime sleepiness, high levels of NOD, and low nocturnal SpO2 percentages, should be prioritized for treatment, alongside those with high levels of severe OSA.

Correlation between Heart Rate Variability and Disease Severity in Obstructive Sleep Apnea

Objective: This study aimed to investigate the variations in Heart Rate Variability (HRV) among individuals with Obstructive Sleep Apnea (OSA) and to explore the relationship between HRV, respiratory parameters, and disease severity. Methods: This prospective study included sixty participants diagnosed with OSA. Polysomnography (PSG) was utilized to assess HRV parameters, including time-domain and frequency-domain measures. Participants were categorized based on the severity of OSA, and data on hemoglobin (HGB), C-reactive protein (CRP), triglyceride (TG) levels, and nocturnal oxygen desaturation (NOD) were collected. Statistical analyses were performed to evaluate the correlations between HRV, respiratory parameters, and disease severity. Results: Among the participants, 23 (38%) had severe OSA, while 17 (28%) were habitual snorers (HS). Hemoglobin, C-reactive protein, and triglyceride levels were significantly higher in patients with severe OSA and NOD compared to HS individuals (p=0.002). Increased Epworth Sleepiness Scale (ESS) scores were associated with higher heart rates during sleep in severe OSA patients compared to HS individuals. NOD (+) patients exhibited statistically higher heart rates during sleep compared to NOD (-) patients (p=0.008). Individuals with an apnea/hypopnea index (AHI) >30, NOD (+), and the lowest SpO2 percentage overnight had significantly lower HRV compared to HS and NOD (-) individuals. Conclusions: In addition to AHI, NOD and the lowest overnight SpO2 are significant markers of elevated cardiovascular risk and are useful for assessing HRV. These findings suggest that cardiovascular risks in OSA patients are heightened both during sleep and wakefulness. Therefore, individuals with severe symptoms, especially those with excessive daytime sleepiness, high levels of NOD, and low nocturnal SpO2 percentages, should be prioritized for treatment, alongside those with high levels of severe OSA.

Association of sex with heart rate variability in atrial fibrillation patients

Abstract Background Sex-specific differences in cardiac autonomic tone have not been thoroughly investigated in patients with atrial fibrillation (AF) but may play a relevant role. Purpose We aimed to investigate cardiac autonomic function of female compared to male AF patients by means of short-term heart rate variability (HRV) analysis. Methods In this cross-sectional analysis, we enrolled 1150 patients from the Swiss-AF cohort study with 5-minute resting ECG recordings in sinus rhythm. We calculated the following HRV parameters: HRV triangular index (HRVI), standard deviation of NN intervals (SDNN), root mean square of successive differences, mean heart rate, power in the high frequency and low frequency range. We fitted linear regression models to analyze the association between gender and HRV variables adjusted for age, intake of betablockers, hypertension, diabetes and heart failure. Results 361 patients (29%) were female (mean age 72.9±7.8 years), 789 (68.6%) were male (mean age 69.8±8.5 years). In the multivariable adjusted models, female sex was associated with significantly lower values of HRVI (β = -0.74; 95% CI -1.44- -0 04, p=0.039) and SDNN (β = 8.95; 95% CI 0.162-17.7, p=0.046). This association persisted in all three age tertiles (<68 years, 68-75 years and ≥ 75 years of age). Conclusions In an elderly AF cohort, female sex is associated with reduced global autonomic activity. Whether this is associated with an adverse prognosis has to be investigated.

Heart rate variability helps classify phenotype in systemic sclerosis

We aimed to develop a systemic sclerosis (SSc) subtypes classifier tool to be used at the patient’s bedside. We compared the heart rate variability (HRV) at rest (5-min) and in response to orthostatism (5-min) of patients (n = 58) having diffuse (n = 16, dcSSc) and limited (n = 38, lcSSc) cutaneous forms. The HRV was evaluated from the beat-to-beat RR intervals in time-, frequency-, and nonlinear-domains. The dcSSc group differed from the lcSSc group mainly by a higher heart rate (HR) and a lower HRV, in decubitus and orthostatism conditions. Stand-up maneuver lowered HR standard deviation (sd_HR), the major axis length of the fitted ellipse of Poincaré plot of RR intervals (SD2), and the correlation dimension (CorDim) in the dcSSc group while increased these HRV indexes in the lcSSc group (p = 0.004, p = 0.002, and p = 0.004, respectively). We identified the 5 most informative and discriminant HRV variables. We then compared 341 classifying models (1 to 5 variables combinations × 11 classifier algorithms) according to mean squared error, logloss, sensitivity, specificity, precision, accuracy, area under curve of the ROC-curves and F1-score. F1-score ranged from 0.823 for the best 1-variable model to a maximum of 0.947 for the 4-variables best model. Most specific and precise models included sd_HR, SD2, and CorDim. In conclusion, we provided high performance classifying models able to distinguish diffuse from limited cutaneous SSc subtypes easy to perform at the bedside from ECG recording. Models were based on 1 to 5 HRV indexes used as nonlinear markers of autonomic integrated influences on cardiac activity.

Do Decision-Making Styles Predict Vagal Control? The Role of Resting Heart Rate Variability.

Decision-making styles are a habit-based propensity that drive behavior and affect daily life. Rational and intuitive decision-making styles have been associated with good mental health. However, the underlying mechanisms are not clear. In the last decade, high basal levels of heart rate variability (HRV) have been proposed as an index of health and emotional control, and this could be one of the variables involved in the effects of decision making on health. Therefore, the aim of this study is to analyze the capability of decision-making styles to predict resting HRV. A cross-sectional study was conducted in a sample of 199 (119 women) young university students, and a resting ECG was recorded to extract frequency domain HRV variables. Subsequently, participants completed sociodemographic data and the General Decision-Making Style questionnaire (GDMS). Results showed that the intuitive style predicted high-frequency HRV, while the avoidant style predicted less low-frequency HRV. This study presents new data on the relationship between decision-making style and HRV, suggesting that the intuitive style has a cardioprotective effect, while the avoidant style is related to lower HRV, which has been associated with health vulnerability. In conclusion, this study contributes to the understanding of HRV and its potential as a biomarker for cognitive styles that may improve health.

Does whole-body vibration improve risk of falls, balance, and heart rate variability in post-COVID-19 patients? A randomized clinical trial

IntroductionWhole-Body Vibration (WBV) can be a therapeutic recovery strategy for patients hospitalized for COVID-19. ObjectivesTo evaluate the effects of a 36-session WBV protocol on the risk of falls, balance, mobility and heart rate variability (HRV). Study designA randomized clinical trial. Methods13 patients affected by COVID-19, trained with WBV, 3×/week on alternate days, totaling 36 sessions, were evaluated before and after the intervention. ResultsWBV training at 2 mm and 4 mm amplitude resulted in a reduction in the risk of falls when compared to Sham (p = 0.023), with effect size of 0.530. No changes were observed for mobility and balance outcomes (p = 0.127) or for any of the HRV variables (p = 0.386). ConclusionWBV training reduced the risk of falls in post-COVID patients. No changes were observed regarding balance and mobility, nor for HRV.

Investigating the Feasibility of Using a Wearable Device to Measure Physiologic Health Data in Emergency Nurses and Residents: Observational Cohort Study.

Emergency departments play a pivotal role in the US health care system, with high use rates and inherent stress placed on patients, patient care, and clinicians. The impact of the emergency department environment on the health and well-being of emergency residents and nurses can be seen in worsening rates of burnout and cardiovascular health. Research on clinician health has historically been completed outside of clinical areas and not personalized to the individual. The expansion of digital technology, specifically wearable devices, may enhance the ability to understand how health care environments impact clinicians. The primary objective of this pilot study was to assess the feasibility and acceptability of using wearable devices to measure and record physiologic data from emergency nurses and resident physicians. Understanding strategies that are accepted and used by clinicians is critical prior to launching larger investigations aimed at improving outcomes. This was a longitudinal pilot study conducted at an academic, urban, level 1 trauma center. A total of 20 participants, including emergency medicine resident physicians and nurses, were equipped with a wearable device (WHOOP band) and access to a mobile health platform for 6 weeks. Baseline surveys assessed burnout, mental health, and expectations of the device and experience. Participants provided open-ended feedback on the device and platform, contributing to the assessment of acceptance, adoption, and use of the wearable device. Secondary measures explored early signs and variations in heart rate variability, sleep, recovery, burnout, and mental health assessments. Of the 20 participants, 10 consistently used the wearable device. Feedback highlighted varying experiences with the device, with a preference for more common wearables like the Apple Watch or Fitbit. Resident physicians demonstrated higher engagement with the device and platform as compared with nurses. Baseline mental health assessments indicated mild anxiety and depressive symptoms among participants. The Professional Fulfillment Index revealed low professional fulfillment, moderate workplace exhaustion, and interpersonal disengagement. This pilot study underscores the potential of wearable devices in monitoring emergency clinicians' physiologic data but reveals challenges related to device preferences and engagement. The key takeaway is the necessity to optimize device and platform design for clinician use. Larger, randomized trials are recommended to further explore and refine strategies for leveraging wearable technology to support the well-being of the emergency workforce.

Hematological and physiological responses in polo ponies with different field-play positions during low-goal polo matches.

Strenuous exercise in traditional polo matches creates enormous stress on horses. Hematological and physiological measures may vary across different field-play positions. This study aimed to investigate the effort intensity and the impact of exertion on hematology and heart rate variability (HRV) in polo ponies with different positions. Thirty-two ponies, divided equally into eight teams, were studied. Each comprises forwards (number 1), midfielders (numbers 2 and 3), and defenders (number 4). Team pairs played the first chukka in four low-goal polo matches. Percent maximum heart rate (%HRmax), indicating ponies' effort intensity, was classified into five zones, including zones 1 (<70%), 2 (70-80%), 3 (80-90%), 4 (90-95%) and 5 (>95%). Hematological and HRV parameters were determined before, immediately after, and at 30-minute intervals for 180 minutes after chukkas; HRV variables were also obtained during warm-up and exercise periods. Results indicated that the number two ponies spent more time in zone 4 (p < 0.05) but less in zone 2 (p < 0.01) than the number four ponies. Cortisol levels increased immediately and 30 minutes afterward (p < 0.0001 for both) and then returned to baseline 60-90 minutes after exertion. Other measures (Hct, Hb, RBC, WBC, neutrophils, and CK enzyme) increased immediately (p < 0.0001 for all) and lasted at least 180 minutes after exertion (p < 0.05-0.0001). HRV decreased during the chukka until approximately 90 minutes afterward (p < 0.05-0.0001). The stress index increased during the chukka and declined to baseline at 60 minutes in number 1-3 ponies but lasted 90 minutes in those at number four. Effort intensity distribution differed among field-play positions. Decreased HRV indicated reduced parasympathetic activity during exercise, extending to 90 minutes after exertion in polo ponies. Defenders seem to experience more stress than those in other positions.

Predictive Model of All-Cause Death in Patients with Heart Failure using Heart Rate Variability.

Central Illustration : Predictive Model of All-Cause Death in Patients with Heart Failure using Heart Rate Variability. Short and long-duration heart rate variability (HRV) data from Holter monitoring could identify predictors of all-cause death in heart failure (HF) patients. To build a predictive model of all-cause death in patients with HF using HRV. Retrospective study including patients with suspected or confirmed HF who were admitted for decompensated HF or syncope that underwent Holter monitoring. In analysis of augmented sympathetic tonus, we evaluated the lowest HRV in nonoverlapping 10-minutes periods throughout 24h continuous electrocardiographic signal recording (short HRV variables). Variables with p<0.01 were included in a multivariate Cox regression model to determine the occurrence of the all-cause death. Variables with statistical significance in Cox regression were chosen to build the predictive model. P<0.05 was considered significant. A total of 116 patients were included, mean age of 71.9±16.3 years, 45.7% men, mean follow-up of 2.83±1.27 years. Thirty-nine deaths occurred (33.6%). By comparing survivors vs. non-survivors, the variables that showed statistical significance were lowest SDNN, lowest rMSSD, age and left ventricular ejection fraction (LVEF). In Cox regression, independent predictors of all-cause death were: age>69 years (HR 3.95, 95%CI 1.64-9.52); LVEF≤57% (HR 4.70, 95%CI 2.38-9.28) and lowest rMSSD≤12ms (HR 5.54, 95%CI 2.04-15.08). An integer value was assigned to each variable. Score<3 showed AUC=0.802 (95%CI 0.72-0.87). In HF patients hospitalized for decompensated HF or syncope, independent long-term predictors of all-cause death were age, LVEF, and 10-minutes rMSSD. These findings indicate that even brief moments of high sympathetic tone can impact survival, specifically in the elderly and patients with HF with reduced ejection fraction.

Heart Rate Variability in Concussed College Athletes: Follow-Up Study and Biological Sex Differences.

Finding reliable biomarkers to assess concussions could play a pivotal role in diagnosis, monitoring, and predicting associated risks. The present study aimed to explore the use of heart rate variability (HRV) in the follow-up of concussions among college athletes and to investigate the relationships between biological sex, symptomatology, and HRV values at baseline and after a concussion. Correlations between measures were also analyzed. A total of 169 (55 females) athletes aged 16 to 22 years old completed baseline testing, and 30 (8 females) concussion cases were followed. Baseline assessment (T1) included psychosocial and psychological questionnaires, symptoms report, and four minutes of HRV recording. In the event of a concussion, athletes underwent re-testing within 72 h (T2) and before returning to play (T3). Baseline findings revealed that girls had higher %VLF while sitting than boys, and a small negligible correlation was identified between %HF and total symptoms score as well as %HF and affective sx. Post-concussion analyses demonstrated a significant effect of time × position × biological sex for %HF, where girls exhibited higher %HF at T3. These findings suggest disruptions in HRV following a concussion and underscore biological sex as an important factor in the analysis of HRV variation in concussion recovery trajectory.

Investigating autonomic nervous system dysfunction among patients with post-COVID condition and prolonged cardiovascular symptoms.

Heart Rate Variability (HRV) and arterial pressure (AP) variability and their responses to head-up tilt test (HUTT) were investigated in Post-COVID-19 syndrome (PCS) patients reporting tachycardia and/or postural hypotension. Besides tachycardia, PCS patients also showed attenuation of the following HRV parameters: RMSSD [square root of the mean of the sum of the squares of differences between adjacent normal-to-normal (NN) intervals] from statistical measures; the power of RR (beat-to-beat interval) spectra at HF (high frequency) from the linear method spectral analysis; occurrence of 2UV (two unlike variation) pattern of RR from the nonlinear method symbolic analysis; and the new family of statistics named sample entropy, when compared to control subjects. Basal AP and LF (low frequency) power of systolic AP were similar between PCS patients and control subjects, while 0 V (zero variation) patterns of AP from the nonlinear method symbolic analysis were exacerbated in PCS patients. Despite tachycardia and a decrease in RMSSD, no parameter of HRV changed during HUTT in PCS patients compared to control subjects. PCS patients reassessed after 6 months showed higher HF power of RR spectra and a higher percentage of 2UV pattern of RR. Moreover, the reassessed PCS patients showed a lower occurrence of 0 V patterns of AP, while the HUTT elicited HR (heart rate) and AP responses identical to control subjects. The HRV and AP variability suggest an autonomic dysfunction with sympathetic predominance in PCS patients. In contrast, the lack of responses of HRV and AP variability indices during HUTT indicates a marked impairment of autonomic control. Of note, the reassessment of PCS patients showed that the noxious effect of COVID-19 on autonomic control tended to fade over time.

Effect of Exercise in a Vector-Protected Arena for Preventing African Horse Sickness Transmission on Physiological, Biochemical, and Behavioral Variables of Horses

During an African horse sickness (AHS) outbreak, horses were able to exercise daily in a net-covered arena, yet the physiological responses to exercise in a netted arena was unknown. In a cross-over study design, eight horses performed a 39-minute aerobic exercise in conventional (CA) and vector-protected arenas (VPA). Horses were slower in some gaits and covered less distance in the VPA arena (P < .01). Cortisol release, hematology, and heart rate variability (HRV) were also examined. An interaction between the riding arena and time was observed in hematocrit (P = .0013), hemoglobin (P = .0012), and red blood cell count (P = .0027) and HRV variables, including mean beat-to-beat (RR) intervals (P < .0001), mean heart rate (P < .0001), sympathetic nervous system (SNS) index (P = .0038) and parasympathetic nervous system (PNS) index (P < .0001). Cortisol concentrations increased during exercise and 30 minutes postexercise in both arenas. Hematocrit, hemoglobin, and red blood cell count increased immediately postexercise in horses in VPA while remaining high from immediate post-exercise to 60 minutes postexercise in horses in CA. HRV decreased during exercise and was not different between horses in both arenas, but a higher RR interval and PNS index, corresponding to lower heart rate and SNS index, were detected during 30 to 60 minutes postexercise in horses in the VPA compared to the CA. Riding horses in different arenas impacted hematological and HRV variables. The greater RR intervals and PNS index, coinciding with the lower SNS index and heart rate, indicated parasympathetic dominance post-exercise in horses in VPA compared to CA.

Effectiveness of Cold Spinal Spray on Blood Pressure and Heart Rate Variability in Patients with Hypertension—A Randomized Controlled Trial

Background: The application of cold to the spine is documented as favourable for reducing blood pressure in patients with hypertension (HTN). However, hydriatic application in the form of a cold spinal spray (CSS) has not yet been explored.Objective: To find the effectiveness of CSS on cardio autonomic variables among males with HTN. Methods: One hundred male patients with HTN visiting the outpatient service were included in this randomized controlled trial. A single session of CSS (15°C–19°C) was given to 50 patients for a period of 20 minutes for the study group, and the control group was made to lie down on the spinal spray tub for 20 minutes without any intervention. Baseline blood pressure and short-term heart rate variability (HRV) measurements were obtained prior to the intervention, followed by a subsequent assessment after a 20-minute interval for both groups. Results: Following 20 minutes of CSS a significant decrease was observed in systolic blood pressure (136.48±14.15 mmHg to 126.20±13.18 mmHg, p&lt;0.001), diastolic blood pressure (87.96±6.77 mmHg to 84.06±6.84 mmHg, p&lt;0.006), pulse pressure (48.44±11.99 mmHg to 42.08±10.88 mmHg, p&lt;0.007), and mean arterial pressure (104.09±8.12 mmHg to 98.05±7.88 mmHg, p&lt;0.001). No significant changes were noted in HRV variables in either of the two patient groups. Conclusion: The current study findings suggest that a single session of CSS intervention could lower both systolic &amp; diastolic blood pressure, pulse pressure and mean arterial pressure in male hypertensive patients. Further studies are needed to find the long-term effect of CSS among patients with HTN.

Autonomic dysregulation in long-term patients suffering from Post-COVID-19 Syndrome assessed by heart rate variability

Post-COVID-19 Syndrome (PCS) is a condition with multiple symptoms partly related to dysregulation of the autonomic nerve system. Assessment of heart rate variability (HRV) using 24 h Holter-ECG may serve as a surrogate to characterize cardiac autonomic activity. A prospective study including 103 PCS patients (time after infection = 252 days, age = 49.0 ± 11.3 years, 45.7% women) was performed and patients underwent detailed clinical screening, cardiopulmonary exercise testing, and 24 h Holter monitoring. Data of PCS patients was compared to 103 CAD patients and a healthy control group (n = 90). After correction for age and sex, frequency-related variables differed in PCS patients compared to controls including LF/HFpower, LF/HFnu, and LF/HF ratio (24 h; p ≤ 0.001). By contrast, these variables were largely comparable between PCS and CAD patients, while sympathetic activation was highest in PCS patients during the 24 h period. Overall, PCS patients showed disturbed diurnal adjustment of HRV, with impaired parasympathetic activity at night. Patients hospitalized during acute infection showed an even more pronounced overactivation of sympathetic activity compared to patients who underwent ambulant care. Our data demonstrate persistent HRV alterations in PCS patients with long-term symptom duration, suggesting a sustained impairment of sympathovagal balance. Moreover, sympathetic overstimulation and diminished parasympathetic response in long-term PCS patients are comparable to findings in CAD patients. Whether HRV variables have a prognostic value in PCS and/or might serve as biomarkers indicating a successful interventional approach warrants further longitudinal studies.

Analyzing the effect of postural change on heart rate variability using multi-distance sample entropy (MDSE)

One of the most studied physiological measures is heart-rate variability. In this research paper, a new nonlinear method called Multi Distance Sample Entropy (MDSE) is proposed to accurately detect the variation of Heart rate variability (HRV) for different body postures and examine its effect on the activity of the autonomic nervous system. The proposed method used a multi-distance function to calculate the distance between other matched vector pairs. The goal of employing considerable distances is to investigate the distance aspect for enhancing the accuracy of recognizing the proper trend of HRV for the postural shift. Thus, the ECG signals of 55 participants were recorded in the supine posture for 10 min and similarly, for 10 min in the standing posture using the BIOPAC®MP36 system. The noise signals have been simulated for varieddata lengths, and their error bars have been plottedusing the proposed and conventional sample entropy (SE) methods to demonstrate the superiority of the proposed MDSE method over the SE. Afterward, the proposed method (MDSE) and other existing methods were applied to the recorded dataset. From the obtained results, it is clear that the proposed method can accurately detect the variation of HRV in supine and standing postures than other applied methods. Using the MDSE method, HRV trends are 6.91% more accurate than Conventional SE and 10.85% more accurate than approximation entropy (AE) for the recorded dataset. The Spearman rank correlation between proposed and applied nonlinear methods has also been evaluated.

Cardiovascular variations in patients with major depressive disorder versus bipolar disorder

BackgroundDifferentiating depression in major depressive disorder and bipolar disorder is challenging in clinical practice. Therefore, reliable biomarkers are urgently needed to differentiate between these diseases. This study's main objective was to assess whether cardiac autonomic function can distinguish patients with unipolar depression (UD), bipolar depression (BD), and bipolar mania (BM). MethodsWe recruited 791 patients with mood disorders, including 191 with UD, 286 with BD, and 314 with BM, who had been drug free for at least 2 weeks. Cardiovascular status was measured using heart rate variability (HRV) and pulse wave velocity (PWV) indicators via finger photoplethysmography during a 5-min rest period. ResultsPatients with BD showed lower HRV but higher heart rates than those with UD and BM. The PWV indicators were lower in the UD group than in the bipolar disorder group. The covariates of age, sex, and body mass index affected the cardiovascular characteristics. After adjusting for covariates, the HRV and PWV variations among the three groups remained significant. Comparisons between the UD and BD groups showed that the variable with the largest effect size was the frequency-domain indices of HRV, very low and high frequency, followed by heart rate. The area under the receiver operating characteristic curve (AUC) for each cardiovascular variable ranged from 0.661 to 0.714. The High-frequency index reached the highest AUC.Limitations.Cross-sectional design and the magnitude of heterogeneity across participants with mood disorders limited our findings. ConclusionPatients with BD, but not BM, had a greater extent of cardiac imbalance than those with UD. Thus, HRV may serve as a psychophysiological biomarker for the differential diagnosis of UD and BD.

Heart rate variability in patients with psychiatric disorders from adolescence to adulthood

ObjectiveAge is associated with changes in autonomic nervous system activity. These changes are assessed using heart rate variability(HRV) indicators; however, the effect of age on HRV in patients with psychiatric disorders remains unclear. Our study aimed to explore this effect and determine its variance across different lifespans. MethodConsecutive patients(N = 3315), comprising 1833 patients with psychotic disorders, 1040 with mood disorders, and 442 with anxiety disorders, were recruited. The patients were divided into four age groups: adolescence(10–24 years), early adulthood(25–39 years), middle adulthood(40–59 years), and late adulthood(60+ years). HRV indicators were measured during a 5-min rest period. ResultsThe heart rate and HRV indices were higher in the adolescent and early adulthood groups than they were in the middle and late adulthood groups(increased HRV is beneficial for health, while reduced HRV is detrimental). Age and all the HRV indices were negatively correlated(r-values 0.153–0.350, p < 0.001), with these correlation patterns being more evident in the adolescent and early adulthood groups than in the middle and late adulthood groups. Stratified by sex, the low-frequency/high-frequency ratio was higher in men than in women across most age groups(p < 0.05), except the late adulthood group(p = 0.085). Stratified by diagnosis, most HRV variables(except very low-frequency) were lower in the psychotic disorder group than they were in the mood and anxiety disorder groups, especially in middle and late adulthood patients. After adjusting for confounders, the HRV variables were significantly associated with age, while older age was associated with lower HRV. ConclusionsThese results indicate that the substantial reduction in HRV with age in patients with psychiatric disorders. The association remains significant after correction for sex, heart rate, and diagnoses; this may prove useful to clinical practice and further research.

Heart rate variability and the quality of life of patients receiving chemotherapy against gynecologic malignancies.

106 Background: Improving quality of life (QOL) of patients with cancer is essential. However, evaluating QOL requires completing QOL questionnaires consisting of 30–40 questions, which is too burdensome for the patients to continue. Therefore, development of the methodology which does not dependent on the adherence of the patients is urgent to evaluate QOL. Recently, heart rate variability (HRV) has been reported to be associated with the autonomic nervous system. This study aims to develop and validate a machine-learning model to predict QOL from HRV. Methods: Fifty patients with gynecological cancers from our hospital were used as test data, and 15 patients with gynecological cancer from other hospitals were used as validation data. Using a mobile application, they recorded daily HRV and weekly QOL questionnaires (EORTC qlq-C30, FACT-G, PHQ9, PRO-CTCAE). A binary classification model was developed using the XgBoost Classifier to predict whether patients experienced at least one of severe numbness, insomnia, depression, and fatigue using their HRV. SHAP values of the HRV used for prediction were clustered into three groups using unsupervised learning (Parametric Umap). QOL indices for each group were compared. Metabolites in serums that contribute to HRV variation were identified using metabolome analysis. Results: Clustering using the SHAP values indicated high, middle, and low QOL groups (Group A, B, and C, respectively). The total score of FACT-G, an index of overall QOL, was 82.4, 72.7, and 67.3 out of 108 (Group A, B, and C, respectively). Global health status, another index of overall QOL was also highest in Group A and lowest in Group C. The score of fatigue was 27.2, 46.3, and 54.9 out of 100; the score of pain was 17.6, 27.2, and 35.8 out of 100; the score of depression was 1.8, 4.5, and 6.6 out of 27 (Group A, B, and C, respectively). The scores of numbness, diarrhea, appetite loss, insomnia and nausea were also highest in the Group C and lowest in the Group A. The HRV of validation datasets also showed a similar classification with total scores of FACT-G as 76.0, 67.8, and 62.1 and the score of depression as 3.8, 5.7 and 8.0 (Group A, B, and C, respectively). Metabolites in serum contributing to HRV variation are Arachidonic acid and Dopamine, which are associated with inflammation and depression. Conclusions: Measuring HRV is a simple way to evaluate the QOL of patients with gynecologic cancers. Monitoring QOL over time using HRV possibly allows early detection of deterioration in QOL, such as complications and side effects of chemotherapy. Clinical trial information: UMIN000038937 .

Fractal complexity alternations in paroxysmal atrial fibrillation patients with and without recurrence after pulmonary vein isolation.

Pulmonary vein isolation (PVI) is a cornerstone therapy for paroxysmal atrial fibrillation (PAF). The variations in nonlinear heart rate variability (HRV) between patients with and without recurrences remain unclear. We aimed to characterize the nonlinear HRV before and after PVI in patients with and without recurrence. Twenty-five drug-refractory PAF patients (56.0 ± 9.1 years old, 20 males) who received PVI were enrolled. Holter electrocardiography were performed before, 1-3, and 6-12 months after PVI. After 8.2 ± 2.5 months of follow-ups after PVI, patients were divided into two groups: the recurrence (n = 8) and non-recurrence (n = 17) groups. Linear and nonlinear HRV variables were analyzed, including the Poincaré Plot analysis and the Detrended Fluctuation Analysis (DFA). The non-recurrence group, but not the recurrence group, had decreased high-frequency component (HF), the root mean square of successive RR interval differences (RMSSD), and the Poincaré Plot index SD1 1-3 months after PVI and increased DFAslope2 6-12 months after PVI. The non-recurrence group's LF/HF ratio and DFAslope1 decreased significantly 1-3 and 6-12 months after PVI, respectively, whereas there was no significant change in the recurrence group after PVI. Significantly reduced vagal tone 1-3 months after PVI, increased long-term fractal complexity 6-12 months after PVI, and decreased sympathetic tone as well as short-term fractal complexity 1-3 and 6-12 months after PVI led to a better AF-free survival after PVI. These findings suggest that neuromodulation and heart rate dynamics play crucial roles in AF recurrence following PVI.

Impact of Heart Rate Variability on Physiological Stress: Systematic Review

Chronic stress overactivates the sympathetic nervous system, which alters the body, mind, and behavior. Purpose Stress can indeed be employed to preserve homeostasis when there is a physical or mental imbalance brought on by damaging stimuli. Currently, there isn't a standard reference point for quantifying stress. The purpose of this meta-analysis is to assess studies that support the use of heart rate variability (HRV) as an indicator of stress. Methods and Materials: Studies concerning HRV that have been published in bibliographic database from 2013 to 2023 were firstly selected. A total of 181 articles were found, 69 in Elsevier, 51 in Google Scholar, 38 PubMed, and 23 in other databases. The criteria selected were human study, HRV reactivity and the HRV as an objective indicator of psychological stress. Only human study was restrained. Finally, ten publications that fit criteria were found. Results: Majority of research selected found that HRV components changed in response to stress brought on by diverse techniques. The most often cited component associated with variance in HRV variables was a drop in the high-frequency band and an increase in the low-frequency band, both of which are markers of diminished parasympathetic activity. HRV may be related to cortical areas that are engaged in evaluating stressful situations, according to neuroimaging research. Conclusion: The findings support the use of HRV for the purpose of evaluating stress and mental health objectively, and neurobiological data suggests that HRV is impacted by stress reactions.