Heart Rate Variability Recordings Research Articles

Assessment of Occupational Based Stress and Internal Coherence Related with Quality of Life Through Heartrate Variability (HRV) - A Cross Sectional Study

Background: This study aimed to evaluate occupation-based stress levels and internal coherence in individuals visiting dental clinics of a tertiary care hospital using heart rate variability (HRV) measures. Occupational stress can significantly influence various aspects of quality of life, including emotional health and cardiovascular risks. Objective: The primary objective was to assess the relationship between occupational stress, internal coherence, and quality of life through HRV metrics in a diverse population. Methods: This cross-sectional study was conducted over six months, enrolling 323 voluntary participants aged 18 years and older, irrespective of gender, ethnic background, or occupation. Participants were informed about the study and provided consent one day prior to their participation. HRV recordings were taken for six minutes in a quiet, temperature-controlled room after a 30-minute relaxation period. HRV sensors were applied to either the index finger or earlobe based on the participant's choice. Data were analyzed using emWave Pro Plus and Kubios HRV software. Statistical analysis was performed using SPSS version 25, with numerical variables reported as medians and interquartile ranges and categorical variables as frequencies and percentages. Results: The study comprised 161 males (49.8%) and 162 females (50.2%), with an age range of 18-65 years. Sympathetic activity increased with age, while younger participants exhibited higher parasympathetic activity. The median SDNN was 78.70 ms (IQR 43.8, 148.0) for males and 60.0 ms (IQR 35.1, 132.2) for females. The coherence levels were low across all age groups, and the stress index scores increased with age. Specifically, the stress index was higher in older age groups, with males aged 54-65 years showing a median stress index score of 45.8% in the high-stress category, compared to 17.9% in males aged 18-29 years. Conclusion: The findings highlight the significant impact of occupational stress on HRV and overall well-being. Sympathetic activity increased with age, and stress levels were higher in older participants. These results underscore the importance of work-life balance and stress management strategies to mitigate cardiovascular risks and improve quality of life.

The Clinical Role of Heart Rate Variability Assessment in Cognitively Impaired Patients and Its Applicability in Community Care Settings: A Systematic Review of the Literature.

Heart rate variability (HRV) correlates well with a person's overall physiological function. Clinically, HRV is successfully used in acute care to identify impending infections, but little is known about its potential in the management of chronic diseases like cognitive decline/dementia. The aim of this study was to identify the best available knowledge about HRV in cognitively impaired populations that might be applied to improve clinical practice in community settings. We conducted a systematic literature search in PubMed, Embase, and Cochrane databases published from January 2009 to August 2022. Eligible studies were selected using Covidence and each study underwent qualitative assessment using the Mixed Method Appraisal Tool. At each stage of selection, each study was reviewed independently by two members of the team, and any disputes were discussed along the way. The literature identified that the brain regions controlling HRV are also those affected by dementias of Alzheimer's type (AD) and Lewy body types (DLB). HRV was impaired in both types, with DLB showing greater impairment in all HRV parameters compared to AD. No studies explored the temporal changes of HRV or its use in the clinical management of people with cognitive impairment (CI). The current lack of standardization of HRV recording and analysis limits its use in clinical practice. HRV may emerge as a potentially useful tool to identify people with early/preclinical memory impairment and help to differentiate AD from DLB. Longitudinal HRV measurement is emerging as a useful way to monitor disease progression and treatment response, and continuous HRV measurement may prove useful in the early identification of sepsis and its complications in patients no longer able to communicate their illness experiences.

The relationship between heart rate variability and glucose clearance in healthy men and women.

Heart rate variability (HRV) is a non-invasive indicator of the activity of the autonomic nervous system, which regulates many physiological functions including metabolism. The purpose of this study was to quantify the relationship between resting markers of HRV and oral glucose tolerance test (OGTT) response. Eighteen healthy individuals (10 males, 8 females, (23.8±2.9 years) underwent a 10-minute resting HRV recording. The final five minutes were evaluated via Kubios HRV Standard for: root mean square of successive differences (RMSSD), standard deviation of normal-to-normal sinus beats (SDNN), high frequency (HF), and low frequency (LF). A standard 2-hour OGTT was then administered. Glucose was measured via finger stick before, 30-minutes post, 1-hour post, and 2-hours post OGTT. Pearson correlations demonstrated that RMSSD, SDNN, HF and LF were strongly correlated to fasting blood glucose (FBG) for the group (p<0.05) but not for glucose area under the curve (AUC). When analyzed by sex, only males demonstrated significant correlations between AUC and RMSSD, SDNN, and LF (p<0.05). An independent samples t-test revealed no sex differences for FBG, AUC, RMSSD, SDNN, HF and LF. These findings provide new and interesting insights into the relationship of autonomic activity and glucose uptake, highlighting sex-based relationships.

Heart rate vARiability and physical activity in inpatient treatMent of burnOut and DepressIon (HARMODI): protocol of a cross-sectional study with up to 8-week follow up

IntroductionChronic stress can cause an imbalance within the autonomic nervous system, thereby affecting cardiovascular and mental health. Physical activity (PA) may have a positive effect on the autonomic nervous system...

Prefrontal activity and heart rate variability during cognitive tasks may show different changes in young and older adults with and without mild cognitive impairment.

Age-related decline in cognitive function is often linked to changed prefrontal cortex (PFC) activity and heart rate variability (HRV). Mild cognitive impairment (MCI), a transitional stage between normal aging and dementia, might have further degeneration beyond aging. This study aimed to investigate the differences between young and older adults with or without MCI in cognitive functions, task-induced PFC activation and HRV changes. Thirty-one healthy young adults (YA), 44 older adults (OA), and 28 older adults with MCI (OA-MCI) were enrolled and compared in this cross-sectional study. Each participant received a one-time assessment including cognitive and executive functions, as well as the simultaneous recording of PFC activity and HRV during a cognitive task paradigm. We observed age-related decrease in global cognitive functions, executive functions, HRV, and increase in PFC activity. The MCI further deteriorated the global cognitive and executive performances, but not the HRV or the prefrontal activation. Older people showed lower performances in general cognitive function and executive function, compensatory increase of PFC activity, and reduced HRV. Older people with MCI had further deterioration in cognitive performance, but not in PFC activation and HRV.

A Preliminary Assessment of Equine Affect in Equine-Assisted Services

ABSTRACT Equine-Assisted Services (EAS) involve health services and adaptive recreation that include equine interactions to promote human wellbeing. While research around the human health outcomes of EAS has grown considerably, there has been limited exploration into the impact of such services on a key service provider, the horse. This study evaluated whether there is variation in how EAS horses experience different types of unmounted interactions with humans. To answer this question, we utilized a mixed method, repeated measures experiment in which 56 human participants and 14 horses, working at a 1:1 ratio, completed a series of three interactions common to EAS: a grooming, a leading, and a maze condition. To measure equine affect, we recorded heart rate variability (HRV) continuously, took eye temperature (ET) immediately after each interaction, and recorded horse behavior. A mixed effects model indicated that horses displayed greater sympathetic activation in the grooming condition than the leading via Low Frequency/High Frequency Ratio (LF:HF: p < 0.001; ET: p = 0.003) and maze conditions (LF:HF: p = 0.005; ET: p < 0.001). Horses also showed significantly more stress-associated behaviors, such as elevated head carriage and pawing, in the grooming condition. These results indicate that there is potential for equine stress during a grooming activity; therefore, more research is needed to determine optimal approaches for addressing horse welfare in unmounted EAS activities involving human interaction.

Motor creativity assessment: A test-retest reliability and validity protocol study in fibromyalgia and healthy women

IntroductionPrevious studies have found brain abnormalities and deficits in cognitive functions in people with fibromyalgia. It is known that choreography or creative tasks significantly generate cognitive improvements. Various methods have been described in the literature to evaluate creative activities using electroencephalography (EEG), such as the imagination of dance improvisations. However, there is the notion that creative solutions can emerge during the action and that creative motor action may reflect new, statistically rare, and adaptive coordination and/or the control solutions performed. AimThis study seeks to establish an operational approach to test how constraints are combined to induce variability of movement and how to evaluate it, but without forgetting the ideation or preparation of the activity as a relevant section in the study of motor creativity. To this end, this study aims to validate and test the reliability and applicability of an innovative test of motor creativity: The Motor Creativity Assessment (MCA), with the aim of achieving an objective score of motor creativity that can be used to test patients and monitor the interventions. Material and methodsto correctly satisfy the requirements of the standard protocol for clinical trials, this study has followed the SPIRIT 2013 Statement Items. A total of 13 women with fibromyalgia and 13 healthy women were included in the study. The individual's cognitive impairment, sleep quality, pain, quality of life, level of physical activity, fear of falling, and the impact of fibromyalgia will be studied. This study develops a specific test of motor creativity without the use of objects, with the aim of achieving an objective score of motor creativity. An observation score sheet allows motor creativity to be analyzed and scored by viewing a video of the creative movement test. The Enobio® instrument (Neuroelectrics, Cambridge, MA, USA) and Neuroelectrics® instrument driver software (NIC1) were used to record EEG and heart rate variability signals.

Application of Vagal-Mediated Heart Rate Variability and Subjective Markers to Optimise Training Prescription: An Olympic Athlete Case Report

Abstract Purpose: The aim of this case study was to investigate whether the variation in parasympathetic branch activity, in conjunction with subjective data, could optimize the training prescription for an elite athlete during an Olympic season. Methods: During the preparatory phase for the Tokyo Olympic Games, a world-class female 3000m steeplechase runner (Age: 20 years, Height: 168 cm, Weight: 52 kg, VO2max: 67.1 mL⋅min⋅kg-1) recorded Heart Rate Variability (HRV), conducted orthostatic tests, and completed subjective evaluations four times a week throughout the different training periods that constitute a pre-Olympic season. The Pearson correlation coefficient and the Shapiro-Wilk test, along with paired T-tests, were used to assess correlations and compare mean differences between variables concerning baseline measurements and each of the other training periods. Results: The natural logarithm of the root mean square of the standard deviation during supine measurement (LnRMSSDsu) exhibited a significant negative correlation with the training load based on Rating of Perceived Exertion (RPE) and sleep quality (P &amp;lt; 0.05). Heart rate during supine measurement (HRsu) showed a significant positive correlation with subjective perceived exertion, sleep quality, stress, muscle soreness, and fatigue (P &amp;lt; 0.01). Compared to the baseline (rest), LnRMSSDsu, HRsu, RPE, and sleep quality were significantly different during the training, camp, and altitude training camp periods. Conversely, markers of standing Heart Rate Variability (HRV) did not differ during competition periods. Conclusion: Standing Heart Rate Variability, when combined with subjective markers, serves as a relevant monitoring tool for adapting training periods to regulate psychophysiological effects.

Heart rate variability and perception of mental stress among medical students and residents at an emergency department

BackgroundWhen Medical Residents (MR) and Medical Students (MS) are assigned to the demanding environment of an Emergency they inevitably encounter stress. The aims of this study are to measure short-term heart rate variability (HRV) before and after shifts, estimate perceived stress levels, and assess the recovery patterns after their shifts. MethodsWe assessed HRV parameters in MS and MR using the wristband physiological monitor Polar® Verify Sense before and after day (DS) and night shifts (NS). Perceived stress levels were evaluated using the simplified State Trait Anxiety Inventory (STAI-S6) and the Subjective Units of Distress Scale. ResultsThis study included 60 participants of which 55% were female with a mean age of 26 years. MS presented significant reduction in sympathetic nervous system index after DS [0.68 (0.01–2.42) vs −0.22 (−0.75–1.13), p < 0.01] and NS [0.87 (−0.28–1.45) vs 0.06 (−0.70–1.04), p < 0.01], while MR maintained the same levels of sympathetic activity [DS: 1.17 (0.04 –2.88) vs 0.93 (0.50–1.41), p = 0.14; NS: 1.37 (0.76–2.21) vs 1.29 (0.35–2.18), p = 0.40]. Psychological data from STAI-S6 showed statistically significant differences when comparing before and after DS in both groups, with more perceived stress after than before DS (MS: 12 ± 4 vs 14 ± 4, p = 0.04; MR: 14 ± 4 vs 16 ± 4, p = 0.04), which was not observed at NS (MS: 12 ± 3 vs 12 ± 3, p = 0.84; MR: 15 ± 3 vs 15 ± 4, p = 0.40). ConclusionsShort-term HRV recordings before and after day or night shifts among MR and MS revealed heightened sympathetic activity preceding each shift, with a more sustained increase observed in the MR population and more perceived stress after day shifts in both groups.

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.

Modifications of short-term heart rate variability in metabolic syndrome: a systematic review and meta-analysis

Abstract Introduction Metabolic syndrome (MS) is a clinical condition in which different non-communicable chronic diseases converge, such as hypertension, diabetes, dyslipidemia and obesity. MS has been related to dysregulation of the autonomic nervous system (ANS). Heart rate variability (HRV) has been widely used as a tool to assess the activity of autonomic function, which could be very useful for diagnosis or monitoring in patients with MS; however, to date, no quantitative analysis of ANS dysfunction in MS has been performed. For this reason, the objective of this systematic review and meta-analysis (MA) is to determine the impact that MS produces in short-term HRV, characterizing the cardiac autonomic dysfunction induced by this pathological condition and the most frequently reported explanatory variables. Methods We searched PubMed, Web of Science and Scopus electronic databases for original works with short-term HRV recordings (15 minutes or shorter) that compared people with MS (MS+) versus healthy people as a control group (MS-). The search was carried out between June 25th, 2022 and September 1st, 2022. Within these databases, the terms used were "metabolic syndrome" linked to "heart rate variability" (HRV), "cardiac autonomic control", "cardiac autonomic function", or "cardiac autonomic modulation". This systematic review and MA was performed according with PRISMA guidelines and registered at the International Prospective Register of Systematic Reviews. Results are reported as standard mean difference [95% CI]. Results Twenty-eight articles were included in the qualitative synthesis and nineteen of them met required criteria to be included in the MA. MS decreased SDNN (-0.40 [-0.5, -0.3], p&amp;lt;0.001), rMSSD (-7.59 [-9.98, -5.19], p&amp;lt;0.001), HF (-0.32 [-0.46, -0.18], p&amp;lt;0.001) and LF (-0.22 [-0.39, -0.06], p&amp;lt;0.01). The ratio LF/HF did not change (0.24 [-0.22, 0.69]). In subsequent subanalyses, we found a decreased in SDNN (-0.99 (-1.45, -0.52], p&amp;lt;0.001), rMSSD (-10.18 [-16.85, -3.52], p&amp;lt;0.01) and HF (-1.04 [-1.97, -0.1] p&amp;lt;0.05) in women. In men, only LF showed a significant decrease (-0.26 [-0.5, -0.2], p&amp;lt;0.05). We could not perform MA for the non-linear variables, but the qualitative analyses showed a decrease in SD1 and increase in SD2 of the Poincare-plot for the MS group. Conclusions MS produced changes in short-term HRV in the time-domain analyses, showing a decrease of SDNN and rMSSD. Regarding the frequency-domain analyses, MS induced a decrease in HF and LF, with the exception of the LF/HF relationship, which was not modified. When gender was taken into account, the MA was only possible in one of both genders (men or women) in rMSSD and LF/HF. Lastly, when data for both men and women were available, gender subanalyses showed a different behavior than the mixed analyses for SDNN, HF and LF, which might point towards a different impact of MS in men and women.

Metabolic syndrome and long-term heart rate variability: a systematic review and meta-analysis

Abstract Introduction Metabolic syndrome (MS) is defined as the convergence over time of a group of non-communicable chronic diseases (hypertension, diabetes, dyslipidemia, obesity). There is agreement that MS is related to pathological changes in the behavior of the autonomic nervous system (ANS). Heart rate variability (HRV) is a very useful tool for assessing autonomous behavior, widely used and that could be useful for the diagnosis and monitoring of MS. However, to date, there are no quantitative analyses using meta-analysis (MA) that have addressed the changes that MS causes on the ANS. Therefore, the objective of this systematic review and MA is to evaluate changes in long-term HRV in patients with MS, in order to characterize the cardiac autonomic dysfunction induced by this pathological condition and the most frequently reported explanatory variables. Methods We searched PubMed, Web of Science and Scopus electronic databases for original works with long-term HRV recordings (24-h holter) that compared people with MS (MS+) versus healthy people as a control group (MS-). The search was carried out between June 25th, 2022 and September 1st, 2022. In the databases selected, the terms used were "metabolic syndrome" linked to "heart rate variability" (HRV), "cardiac autonomic control", "cardiac autonomic function", or "cardiac autonomic modulation". This systematic review and MA was performed according with PRISMA guidelines and registered at the International Prospective Register of Systematic Reviews (CRD42022358975). Results are reported as standard mean difference [95% CI]. Results Thirteen articles were included in the qualitative synthesis and seven of them met required criteria to be included in the MA. MS decreased SDNN (-0.33 [-0.57, -0.09], p=0.008), LF (-0.40 [-0.51, -0.28], p&amp;lt;0.0001), VLF (-0.35 [-0.50, -0.21], p p&amp;lt;0.0001)) and TP (-0.24 [-0.43, -0.05], p=0.01). The MA did not find significant differences in rMSSD (-0.09 [-0.31, 0.13], p=0.41), HF (-0.29 [-0.61, 0.03], p=0.07) and LF/HF (-0.04 [-0.45, 0.36], p=0.84). No article reported information by gender. In the case of the non-linear variables, the information reported was not enough to carry out the MA, but the qualitative analyses showed no change in SD1 of the Poincare plot and a decrease in the multiscale entropy. For the SD2 of the Poincare plot and alfa-1 of the detrended fluctuation analyses, the results are not conclusive. Conclusions The analysis of HRV (time-domain) in long recording periods showed that patients with MS have lower values in the SDNN and no significant changes in rMSSD. Regarding the frequency domain analysis, we found that MS induced a significant decrease in LF, VLF and TP. The MA did not show changes in HF and LF/HF, and quantitative analyses of non-linear parameters could not be performed.

Abstract 14635: Prognostic Value of Heart Rate Variability in Black Americans: The Jackson Heart Study

Background: The prognostic value of heart rate variability (HRV) in Black Americans (BAs), who have distinct cardiac risk profiles, is not well studied. We aimed to investigate the association between HRV, all-cause mortality, and cardiovascular events in the Jackson Heart Study (JHS). Methods: We analyzed data from JHS participants who had HRV readings at baseline (2000-2004). HRV was measured as the standard deviation between subsequent R-waves on a 12-lead EKG. Data were analyzed up to December 31, 2014. Outcomes of interest were all-cause mortality and cardiovascular events (composite of incident stroke and coronary heart disease). Cox regression models were used to estimate hazard ratios (HRs) for the hazard of events in participants with an HRV below the median versus those with an HRV above the median. Restricted cubic splines (RCS) were used to explore non-linear interactions. All analyses were adjusted for age, sex, smoking, clinically relevant comorbidities, and risk factors. Results: Among the 3627 participants (mean age: 55.1 years; female: 62.4%), the median [IQR] HRV was 22.3ms [13.7, 36.1]. At baseline, participants with HRV below the median had a higher prevalence of several cardiometabolic diseases. Adjusted Cox regression showed that HRV below the median was associated with a 32% increased hazard of all-cause mortality (HR: 1.32 [1.09, 1.60]; P = 0.005) and a non-significant increase in incident cardiovascular events (HR: 1.28 [0.99, 1.66]; P = 0.059); Figure 1A . RCS suggested HRV has a non-linear relationship with all-cause mortality (P-nonlinearity: 0.0076) and cardiovascular events (P-nonlinearity: 0.0162), with the hazard of events beginning to increase sharply at HRV &amp;lt;25ms ( Figure 1B ). Conclusion: BAs had a higher mortality hazard associated with lower HRV readings, specifically &amp;lt;25ms. Consumer wearable sensors commonly record HRV, and our findings suggest that HRV could serve as a practical prognostic tool for this population.

Accuracy and clinical utility of heart rate variability derived from a wearable heart rate monitor in patients undergoing major abdominal surgery.

Low heart rate variability (HRV) can potentially identify patients at risk of intraoperative hypotension. However, it is unclear whether cheaper, readily accessible consumer heart rate (HR) monitors can provide similar utility to clinical Holter electrocardiograph (ECG) monitors. The objectives of this study were (1) to assess the validity of using the Polar H10 HR monitor as an alternative to a clinical Holter ECG and (2) to test total power (TP) as a predictor of intraoperative hypotension. The primary outcome was the level of agreement between Polar H10 and Holter ECG. Twenty-three patients undergoing major abdominal surgery with general anesthesia had 5-minute HR recordings taken concurrently with both devices during a pre-anesthetic consultation. Agreement between Polar H10 and Holter ECG was compared via Bland-Altman analysis and Lin's Concordance Correlation Coefficient. Patients were divided into groups based on TP < and TP > . Intraoperative hypotension was defined as MAP < 60 mmHg, systolic blood pressure < 80 mmHg, or 35% decrease in MAP from baseline.There was substantial agreement between Polar H10 and Holter ECG for average R-R interval, TP and other HRV indices. Reduced TP (< 500 ) had a high sensitivity (80%) and specificity (100%) in predicting intraoperative hypotension. Patients with reduced TP were significantly more likely to require vasoactive drugs to maintain blood pressure.The substantial agreement between Polar H10 and Holter ECG may justify its use clinically. The use of preoperative recordings of HRV has the potential to become part of routine preoperative assessment as a useful screening tool to predict hemodynamic instability in patients undergoing general anesthesia.

Short-Term Heart Rate Variability in Metabolic Syndrome: A Systematic Review and Meta-Analysis.

Our aim was to determine the differences in short-term heart rate variability (HRV) between patients with metabolic syndrome (MS) and healthy controls. We searched electronic databases for primary works with short-term HRV recordings (≤30 min) that made comparisons between individuals with MS versus healthy controls. This systematic review and meta-analysis (MA) was performed according to PRISMA guidelines and registered at PROSPERO (CRD42022358975). Twenty-eight articles were included in the qualitative synthesis and nineteen met the criteria for the MA. Patients with MS showed decreased SDNN (-0.36 [-0.44, -0.28], p < 0.001), rMSSD (-7.59 [-9.98, -5.19], p < 0.001), HF (-0.36 [-0.51, -0.20], p < 0.00001) and LF (-0.24 [-0.38, -0.1], p = 0.001). In subsequent subanalyses, we found a decrease in SDNN (-0.99 (-1.45, -0.52], p < 0.001), rMSSD (-10.18 [-16.85, -3.52], p < 0.01) and HF (-1.04 [-1.97, -0.1] p < 0.05) in women. In men, only LF showed a significant lower value (-0.26 [-0.5, -0.02], p < 0.05). We could not perform MA for non-linear variables. Patients with MS showed changes in time-domain analyses, with lower values in SDNN and rMSSD. Regarding frequency-domain analyses, MS patients showed a decrease in HF and LF When sex was used as a grouping variable, the MA was only possible in one of both sexes (men or women) in rMSSD and LF/HF. Lastly, when data for both men and women were available, subanalyses showed a different behavior compared to mixed analyses for SDNN, HF and LF, which might point towards a different impact of MS in men and women.

Heart rate variability and tension-type headache: A population-based cross-sectional study

BackgroundThe relationship between tension-type headache (TTH) and autonomic functions is poorly understood, although TTH is one of the most prevalent disorders in the general population. The aim of this study was to investigate the direct and indirect effects of TTH on the autonomic functions measured by heart rate variability (HRV). MethodsThis population-based cross-sectional study was carried out in the general population of Ulaanbaatar between July and September in 2020. After physical examination, trained researchers applied structured interviews to examine the remote history of TTH and mental distress, followed by a recording of HRV to detect autonomic activity. Psychological factors and the quality of life were measured using Hospital Anxiety Depression Scale (HADS), Pittsburgh Sleep Quality Index (PSQI), and the World Health Organization Quality of Life–Brief (WHOQOL-BREF). Binary logistic regression and GLM mediation model analysis were used to examine the effects of risk factors on the associations between TTH and autonomic functions. ResultsAmong participants (n = 217, mean age=41.8 ± 11.5 years), a total of 117 (53.9%) participants had a remote history of TTH. The age and sex-adjusted prevalence was 43%. Groups did not differ statistically in the HRV indices. LF/HF (ratio of low-frequency to high frequency), the index of sympathovagal balance, was correlated with the HADS anxiety. TTH was associated with mental distress. Binary logistic regression analysis confirms the relationship suggesting that TTH was associated with increased likelihood of mental distress, and decreasing RMSSD (root mean square of the sum of the squares of differences between adjacent NN intervals) and pNN50 (NN50 divided by the total number of NN intervals) were the independent predictors of TTH. GLM mediation model indicated that the relationship between TTH and RMSSD was mediated by mental distress. ConclusionsThe present study suggests that mental distress is a critical factor in the association between TTH and autonomic dysfunction. Additionally, our findings demonstrate the influence of age and gender on TTH. These results highlight the need to understand the mechanisms underlying pathophysiology to facilitate targeted and efficacious prevention and management approaches for TTH.

Adynamic response to cold pain reflects dysautonomia in type 1 diabetes and polyneuropathy

Cardiac autonomic neuropathy (CAN), widely assessed by heart rate variability (HRV), is a common complication of long-term diabetes. We hypothesized that HRV dynamics during tonic cold pain in individuals with type 1 diabetes mellitus (T1DM) could potentially demask CAN. Forty-eight individuals with long-term T1DM and distal symmetrical polyneuropathy and 21 healthy controls were included. HRV measures were retrieved from 24-h electrocardiograms. Moreover, ultra-short-term HRV recordings were used to assess the dynamic response to the immersion of the hand into 2 °C cold water for 120 s. Compared to healthy, the T1DM group had expectedly lower 24-h HRV measures for most components (p < 0.01), indicating dysautonomia. In the T1DM group, exposure to cold pain caused diminished sympathetic (p < 0.001) and adynamic parasympathetic (p < 0.01) HRV responses. Furthermore, compared to healthy, cold pain exposure caused lower parasympathetic (RMSSD: 4% vs. 20%; p = 0.002) and sympathetic responses (LF: 11% vs. 73%; p = 0.044) in the T1MD group. QRISK3-scores are negatively correlated with HRV measures in 24-h and ultra-short-term recordings. In T1DM, an attenuated sympathovagal response was shown as convincingly adynamic parasympathetic responses and diminished sympathetic adaptability, causing chronometric heart rhythm and rigid neurocardiac regulation threatening homeostasis. The findings associate with an increased risk of cardiovascular disease, emphasizing clinical relevance.

An Examination of Heart Rate Variability at Anaerobic Threshold and Respiratory Compensation Points During Cardiopulmonary Exercise Test

The aim of this study is to examine the changes in HRV values before, during (at AT and RC) and after maximal incremental cardiopulmonary exercise test. The sample comprised 121 healthy men who recreational do exercise 2-3 days a week. (age: 30.5 ± 4.6 years, height: 177.8 ± 6.1 cm; weight: 80.2 ± 10.2 kg). Anthropometric measurements were measured by using body analyzer, and aerobic capacities of participants were measured by using the cardiopulmonary exercise test via the Bruce protocol. According to this, heart rate variability recordings were taken at seven stages during the cardiopulmonary exercise test: before the test (1), at the beginning of the test (2), between the beginning of the test and the anaerobic threshold (3), at the anaerobic threshold (4), between the anaerobic threshold and the respiratory threshold (5), at the respiratory threshold (6), and finally (7), 30 seconds after the cardiopulmonary exercise test. Repeated measures analysis of variance (ANOVA) was used to compare the HRV values obtained from the test stages. In conclusion, using a gas analyzer during cardiovascular exercise testing, HRV values (MeanRR, SDNN, RMSSD, LFnu) determined at seven stages continue to decrease from the beginning. A rest period of 30 seconds (passive rest) immediately after completing the exercise does not seem to be sufficient for recovery. According to the results of this study, it can be considered that the sympathetic nervous system activity (LFnu) exhibits a more pronounced appearance at threshold zones.

Effects of man-made electromagnetic fields on heart rate variability parameters of general public: a systematic review and meta-analysis of experimental studies.

The effects of man-made electromagnetic fields (EMFs) on the cardiovascular system have been investigated in many studies. In this regard, the cardiac autonomic nervous system (ANS) activity due to EMFs exposure, assessed by heart rate variability (HRV), was targeted in some studies. The studies investigating the relationship between EMFs and HRV have yielded conflicting results. We performed a systematic review and meta-analysis to assess the data's consistency and identify the association between EMFs and HRV measures. Published literature from four electronic databases, including Web of Science, PubMed, Scopus, Embase, and Cochrane, were retrieved and screened. Initially, 1601 articles were retrieved. After the screening, 15 original studies were eligible to be included in the meta-analysis. The studies evaluated the association between EMFs and SDNN (standard deviation of NN intervals), SDANN (Standard deviation of the average NN intervals for each 5 min segment of a 24 h HRV recording), and PNN50 (percentage of successive RR intervals that differ by more than 50 ms). There was a decrease in SDNN (ES=-0.227 [-0.389,-0.065], p=0.006), SDANN (ES=-0.526 [-1.001,-0.05], p=0.03) and PNN50 (ES=-0.287 [-0.549,-0.024]). However, there was no significant difference in LF (ES=0.061 (-0.267, 0.39), p=0.714) and HF (ES=-0.134 (0.581, 0.312), p=0.556). In addition, a significant difference was not observed in LF/HF (ES=0.079 (-0.191, 0.348), p=0.566). Our meta-analysis suggests that exposure to the environmental artificial EMFs could significantly correlate with SDNN, SDANN, and PNN50 indices. Therefore, lifestyle modification is essential in using the devices that emit EMs, such as cell phones, to decrease some signs and symptoms due to EMFs' effect on HRV.

Differences in Long-Term Heart Rate Variability between Subjects with and without Metabolic Syndrome: A Systematic Review and Meta-Analysis.

Our aim was to determine the impact that metabolic syndrome (MS) produces in long-term heart rate variability (HRV), quantitatively synthesizing the results of published studies to characterize the cardiac autonomic dysfunction in MS. We searched electronic databases for original research works with long-term HRV recordings (24 h) that compared people with MS (MS+) versus healthy people as a control group (MS-). This systematic review and meta-analysis (MA) was performed according to PRISMA guidelines and registered at PROSPERO (CRD42022358975). A total of 13 articles were included in the qualitative synthesis, and 7 of them met the required criteria to be included in the MA. SDNN (-0.33 [-0.57, 0.09], p = 0.008), LF (-0.32 [-0.41, -0.23], p < 0.00001), VLF (-0.21 [-0.31, -0.10], p = 0.0001) and TP (-0.20 [-0.33, -0.07], p = 0.002) decreased in patients with MS. The rMSSD (p = 0.41), HF (p = 0.06) and LF/HF ratio (p = 0.64) were not modified. In long-term recordings (24 h), SDNN, LF, VLF and TP were consistently decreased in patients with MS. Other parameters that could be included in the quantitative analysis were not modified in MS+ patients (rMSSD, HF, ratio LF/HF). Regarding non-linear analyses, the results are not conclusive due to the low number of datasets found, which prevented us from conducting an MA.