Reduced heart rate variability and new-onset hypertension: insights into pathogenesis of hypertension: the Framingham Heart Study

Improving Cardiovascular Health Through the Consideration of Social Factors in Genetics and Genomics Research: A Scientific Statement From the American Heart Association

Cardiovascular health (CVH) is affected by genetic, social, and genomic factors across the life course, yet little research has focused on the interrelationships among them. An extensive body of work has documented the impact of social determinants of health at both the structural and individual levels on CVH, highlighting pathways in which racism, housing, violence, and neighborhood environments adversely affect CVH and contribute to disparities in cardiovascular disease. Genetic factors have also been identified as contributors to risk for cardiovascular disease. Emerging evidence suggests that social factors can interact with genetic susceptibility to affect disease risk. Increasingly, social factors have been shown to affect epigenetic markers such as DNA methylation, which can regulate gene and protein expression. This is a potential biological mechanism through which exposure to poor social determinants of health becomes physically embodied at the molecular level, potentially contributing to the development of suboptimal CVH and chronic disease, thus reinforcing and propagating health disparities. The objective of this statement is to highlight and summarize key literature that has examined the joint associations between social, genetic, and genomic factors and CVH and cardiovascular disease.

Vagal Nerve Biofeedback Intervention for Improving Health Outcomes Among Ukrainian Forced Migrants: A Proof-of-Concept Study

BACKGROUND

The ongoing conflict in Ukraine has forced numerous migrants into neighboring countries, many suffering from pre-existing or newly acquired physical and mental health conditions. Addressing these complex challenges in humanitarian settings requires innovative, evidence-based interventions that are cost-effective and easy to administer. Drawing upon research highlighting the vagus nerve's role in regulating well-being, we hypothesized that vagal nerve activation could offer a promising therapeutic approach.

METHOD

We conducted a proof-of-concept study in which 21 Ukrainian forced migrants were trained in a biofeedback-guided paced breathing intervention designed to stimulate the vagus nerve and promote self-regulation of stress response systems. Changes in pain perception, perceived stress, blood pressure, and heart rate were assessed before and after the vagal breathing intervention using a t-test. Correlations were examined at baseline.

RESULTS

Statistically significant improvements were observed in all measures except systolic blood pressure, providing preliminary evidence for the efficacy of vagal nerve activation in alleviating stress-related health symptoms.

CONCLUSIONS

This study demonstrates the feasibility and therapeutic potential of a vagal nerve-activating intervention in a humanitarian setting. These findings warrant replication in larger, controlled trials. If substantiated, this low-cost, scalable intervention could help mitigate health burdens among forced migrant populations worldwide.

Analysis of changes in heart rate variability after prolonged ultra-high plateau residence in young healthy population: a cross-sectional study

Objective

This study aims to investigate changes in the autonomic nervous system (ANS) by analyzing the characteristics of heart rate variability (HRV).

Methods

A portable 3-lead dynamic electrocardiogram monitoring device was used to collect HRV data from the participants. Based on the inclusion and exclusion criteria, a total of 52 volunteers from the Xinjiang Hetian area (ultra-high plateau group, approximately 5300 m altitude) and 56 volunteers from the Sichuan Chengdu area (plain group, approximately 500 m altitude) were enrolled for the 24-hour long-term HRV data collection. A cross-sectional comparison was made between the groups in terms of various HRV time-domain, frequency-domain, and nonlinear indices. The diurnal and nocturnal variations in HRV and ANS after prolonged residence in the ultra-high plateau were further explored by dividing the day into daytime and nighttime periods and calculating the ΔHRV values. Additionally, the participants' heart rate and sleep conditions were analyzed.

Results

Compared to the plain group, the ultra-high plateau group showed a significant reduction in overall HRV, with decreased indices of vagal activity (RMSSD, NN50, pNN50, HF, HF norm, and SD1) and increased indices of sympathetic activity (LF norm). The ANS balance indices were increased (LF/HF) and decreased (SD1/SD2), respectively. More importantly, although the diurnal and nocturnal trends of various HRV indices in the ultra-high plateau group were consistent with the plain group, the △HRV value analysis indicated that the ultra-high plateau group had increased △LF (95% CI: 10.20 to 271.60, P = 0.031) and △LF/HF (95% CI: -2.23 to -0.49, P < 0.001), and decreased △HF (95% CI: -383.10 to -35.50, P = 0.012) and △S (95% CI: -12149.47 to -2759.29, P = 0.001). Additionally, in the ultra-high plateau group, both the mean and minimum heart rates were elevated compared to the plain group (84.67 ± 1.37 vs. 73.2 ± 0.93 beats/min and 52.9 ± 1.37 vs. 47.57 ± 0.73 beats/min, respectively, P < 0.001), while the maximum heart rate was reduced (135.21 ± 1.63 vs. 144.43 ± 3.22 beats/min, P = 0.012). Furthermore, the ultra-high plateau group had a significant increase in the number of awakenings (18.27 ± 1.14 vs. 15.34 ± 1.43, P = 0.046) and the Apnea-Hypopnea Index (AHI) (20.14 ± 2.47 vs. 11.36 ± 0.76, P < 0.001).

Conclusion

Prolonged residence in the ultra-high plateau reduces HRV, cardiac reserve capacity, and sleep quality in healthy young adults, diminishes the diurnal recovery capacity of the vagal nerve, and leads to a shift in ANS balance towards reduced vagal activity and enhanced sympathetic activity.

Blood Pressure and Heart Rate Response to Orthostasis in Somali Americans

PURPOSE

Cardiovascular health disparities are present in African Americans, but it remains unknown whether this phenomenon affects Somali Americans. Study of Somali Americans is warranted due to distinct genetic and cultural differences from African Americans of western African ancestry. Orthostatic hemodynamic responses have implications for cardiovascular risk, especially among African American females. We sought to examine race and sex differences in systolic (SAP) and diastolic (DAP) arterial pressure and heart rate (HR) responsiveness to standing. We hypothesized that SAP, DAP, and HR change from supine to standing position would be higher in Somali Americans.

METHODS

We studied blood pressure and HR responsiveness in 139 (70 Somali, age 29 ± 10 years; 69 White, age 31 ± 9 years) participants. Supine SAP, DAP, and HR were measured after at least 5 min of supine rest, and again after 1 min of standing. SAP, DAP, and HR change was compared between groups.

RESULTS

ΔSAP and ΔDAP were similar between groups (race × sex: p > 0.05). However, HR responsiveness to orthostasis varied between race and sex comparisons (race × sex: p = 0.011). Somali females exhibited an augmented HR response to orthostasis compared to White females (Δ19 ± 13 vs. 11 ± 9 beats/min, p = 0.005) and Somali males (Δ19 ± 13 vs. 12 ± 9 beats/min, p = 0.020).

CONCLUSION

ΔHR with standing is augmented in young female Somali Americans. These findings highlight an early potential impairment in hemodynamic regulation that may heighten future cardiovascular risk. Further work is warranted to identify the potential autonomic nervous system underpinnings that may contribute to potentiated orthostatic responses and cardiovascular risk in Somali American females. Trial Registration www.

CLINICALTRIALS

gov ; unique identifier, NCT04124848; NCT05411029; NCT03308578.

Investigating the Visit-to-visit Repeatability of Autonomic Neuropathy Assessment Measures in Healthy Subjects

Background

Autonomic neuropathy assessment is needed for the diagnosis and prognostication of different clinical disorders. Heart rate variability (HRV) and autonomic reactivity assessment by Ewing's battery of tests form the cornerstones of laboratory assessment of cardiac autonomic neuropathy evaluation.

Purpose

While these tests are routinely used, there are conflicting reports regarding the visit-to-visit repeatability of these tests. Therefore, we assessed autonomic measures derived using aforementioned tests on multiple visits in healthy subjects.

Methods

We enrolled 31 healthy subjects and performed autonomic function evaluation on five visits by assessment of HRV and autonomic reactivity on day 1 forenoon and afternoon, next day, one week later and one month later. Repeatability assessment was evaluated using Intraclass correlation coefficients. Values were defined as moderate, good and excellent based on previously reported criteria.

Results

Thirty-one subjects completed all five visits (17 males, 14 females; mean age = 29 ± 5.44 years). While time-domain measures demonstrated good to excellent repeatability, frequency-domain measures were only moderately repeatable. Autonomic reactivity indices also displayed good to excellent repeatability with the exception of blood pressure response to orthostatic challenge which was moderately repeatable.

Conclusion

We recommend that sole reliance on frequency domain metrics for HRV assessment should be avoided. HRV indices and autonomic reactivity measures may continue to be used for cardiac autonomic neuropathy assessment.

Heart rate variability as a digital biomarker for frailty in cardiovascular patients

BACKGROUND

Frailty is a syndrome associated with age-related impairments in multiple organ systems, of which the autonomic nervous system plays a fundamental role. Measurement of heart rate variability (HRV) is a non-invasive method to evaluate the autonomic activity and gain insights into cardiovascular health and potentially, frailty. A few small studies have explored the relationship between HRV and frailty, with promising but conflicting results.

OBJECTIVE

To investigate the relationship between HRV and frailty among adult patients with cardiovascular disease.

DESIGN

A cross-sectional study was conducted using clinical data.

SETTING

Data were collected from an ambulatory cardiology clinic.

PARTICIPANTS

The cohort comprised 155 patients with a mean age of 67 years (44 % female).

MEASUREMENTS

HRV was assessed seated at rest for 2.5 min using a finger-based photoplethysmography (PPG) device. Frailty was assessed using the Clinical Frailty Scale (CFS), with a score ≥5 considered frail. Associations between HRV and frailty were examined using a Spearman correlation matrix and multivariable ordinal regression model. The LF/HF ratio (a frequency-domain measure reflecting imbalances between sympathetic and parasympathetic activity) was the primary HRV measure analyzed.

RESULTS

The prevalence of frailty was 15 %. Among all HRV measures, the LF/HF ratio was most closely correlated with frailty (p < 0.001). In the multivariable model, each 1 standard deviation decrease in LF/HF ratio was associated with a 1.1-point increase in CFS (95 % CI 0.7-1.6, p < 0.001). The optimal ROC cutoff at which the LF/HF ratio was associated with frailty is ≤ 0.37.

CONCLUSIONS

The LF/HF ratio is inversely correlated with the CFS and independently associated with frailty. Measurement of HRV is a promising technique to enrich existing frailty scales and assist in frailty assessments in an ambulatory cardiology clinic.

Autonomic cardiac control independently predicts incident hypertension and systolic blood pressure in a multi-ethnic population: The HELIUS study

AIMS

Cross-correlation baroreflex sensitivity (xBRS) and heart rate variability (HRV) are measures of autonomic cardiac control and are associated with hypertension. However, their value in predicting new-onset hypertension and changes in systolic blood pressure (SBP) remains elusive.

METHODS

We used longitudinal data of participants with- and without a history of cardiovascular disease from the HEalthy Life In an Urban Setting (HELIUS) study. A non-invasive continuous finger blood pressure measurement at baseline was used to calculate xBRS and HRV. In normotensives at baseline we calculated the odds ratio (OR) of developing hypertension at follow-up. In the full cohort we assessed the change in SBP between baseline and follow-up using linear regression. Subgroup analyses were performed in the younger (<50 years) and older (≥50 years) participants.

RESULTS

Median follow-up was 6.6 years (IQR 5.8-7.4). A 50% lower xBRS at baseline was independently associated with a 1.31 higher OR (95% CI 1.09-1.57) of developing hypertension at follow-up. No significant associations between the standard deviation normal-to-normal interval (SDNN) or the root mean square of differences in successive normal-to-normal interval (RMSDD), and new-onset hypertension were found. Compared to the lowest tertile, an xBRS in the highest tertile was associated with a 3.61 mmHg (95%CI 2.50-4.71) higher increase in SBP over time, whereas this was 1.11 mmHg (95%CI 0.12-2.09) and 1.76 mmHg (95%CI 0.73-2.79) for SDNN and RMSDD.

CONCLUSION

In the general population, a lower xBRS is associated with increased odds of developing hypertension, and a steeper increase in SBP over time.

Neuroception of safety is associated with elevated heart rate variability in the laboratory and more frequent heart rate variability increases in everyday life

OBJECTIVE

Feeling comfortable and safe has been discussed to foster health and well-being. However, the pathways to better health are complex, involving both behavioral and physiological routes.

METHODS

In this study, we examined the role of safety perception for cardiac health by (1) examining associations with baseline heart rate variability (HRV; Study 1) and (2) evaluating a novel measure of autonomic cardiac flexibility in daily life, namely increases in HRV independent of metabolic demands (ImdHRVi; Study 2).

RESULTS

Study 1 (N = 76) found evidence for a positive association between vagally mediated HRV and the Neuroception of Psychological Safety scale (Morton L, Cogan N, Kolacz J, et al. "A new measure of feeling safe: developing psychometric properties of the Neuroception of Psychological Safety Scale (NPSS)": Correction. Psychol Trauma. 2022; https://doi.org/10.1037/tra0001374), thus suggesting a link between safety and cardiac vagal regulation. In Study 2, a sample of N = 245 adult volunteers participated in a four-day-ambulatory assessment measuring HRV and bodily movement. A regression was calculated between HRV and bodily movement for 12 h of the first recording day, which was then used to calculate minute-by-minute ImdHRVi (beyond those predicted by bodily movement) in the following days. It turned out that safety perception predicted more episodes of ImdHRVi in everyday life, even after controlling for several confounds.

CONCLUSIONS

Findings suggest that feeling safe and everyday life cardiac autonomic regulation are interrelated, thus possibly contributing to adaptive adjustment and health.

Dyslipidemia Impacts Cardiometabolic Health and CVD Risk in a Relatively Young Otherwise Healthy Population

Dyslipidemia, abnormal levels of lipids in the bloodstream, is associated with cardiovascular disease risk (CVD). The purpose of this study was to evaluate the effects of dyslipidemia on cardiometabolic health in relatively young, healthy adults. Participants were 54 healthy males and females aged 18-60 years. Participants were assessed for anthropometrics, body composition, blood pressure and vascular stiffness indicators, microvascular health, and glucose and lipid levels. Using a cross-sectional approach, participants were characterized and grouped as having dyslipidemia or not, and then statistically assessed to determine whether differences in other cardiometabolic health measures existed between the groups. There were significant differences between groups for body weight and composition (total mass, muscle mass, visceral fat, bone mass, and body mass index, all, p < 0.027, Cohen's d > 0.605) with the dyslipidemia group being higher. There were significant differences between groups for peripheral and central blood pressures (all, p < 0.003, Cohen's d > 0.899), as well as for vascular stiffness indicators (pulse pressure, augmentation pressure, augmentation index, augmentation index 75) (all, p < 0.022, Cohen's d > 0.672) with elevations noted in the dyslipidemia group. Ten-year CVD risk was significantly different between groups, with an average risk of 0.8% in the normal lipids group and a risk of 5.4% in the dyslipidemia group (p < 0.001, Cohen's d = 1.260). However, there were no significant differences in macro- or micronutrient intake between groups (all, p > 0.166, Cohen's d < 0.412). There is a significant impact on cardiometabolic health in individuals with dyslipidemia who are otherwise healthy, which may increase individual risk for CVD. Trial Registration: ClinicalTrials.gov identifier: NCT06544915.

The Effect of Yoga Nidra Intervention on Blood Pressure and Heart Rate Variability Among Hypertensive Adults: A Single-arm Intervention Trial

Background Hypertension [blood pressure (BP) >130/80 mmHg] contributes significantly to cardiovascular morbidity and mortality. Lifestyle modifications, including mindfulness-based practices like Yoga, meditation, and relaxation techniques, have emerged as promising adjuncts to pharmacotherapy. This study aimed to explore the acute effects of Yoga Nidra (YN) on BP in essential hypertension and the potential mechanisms of the effect of YN on BP, in the form of changes in heart rate variability (HRV) components. Methods A total of 32 hypertensive individuals (mean age: 43 ±0.54 years; 22 males, 10 females) were enrolled at the Lifestyle Disease Clinic. Patients were provided regular consultation and pharmacotherapy. BP and HRV were assessed before and after a 16-minute YN session. HRV parameters included time and frequency domain measures. Statistical analysis included linear regression to study the relationship of components of HRV with those of the changes in BP. Results Following YN intervention, there was a significant reduction in both systolic BP (SBP) (7 mmHg) and diastolic BP (DBP) (6 mmHg). HRV analysis revealed significant increases. Regression analysis showed changes in SBP having significant coefficients. Conclusions A single session of YN reduced the systolic and diastolic BP and increased HRV parameters. Regression analyses showed that the reduction in BP can be explained by an increase in HRV parameters. Thus, this study demonstrates the positive effect of YN as an intervention for essential hypertension and also the potential mechanisms behind it, which can be explained by the Neurovisceral Integration Model.

Blood Pressure and Heart Rate Response to Orthostasis in Somali Americans

Purpose

Cardiovascular health disparities are present in African Americans, but it remains unknown whether this phenomenon affect Somali Americans. Study of Somali Americans is warranted due to distinct genetic and cultural differences from African Americans of western African ancestry. Orthostatic hemodynamic responses have implications for cardiovascular risk, especially among African American females. We sought to examine race and sex differences in systolic (SAP) and diastolic (DAP) arterial pressure and heart rate (HR) responsiveness to standing. We hypothesized that SAP, DAP, and HR change from supine to standing position would be higher in Somali Americans.

Methods

We studied blood pressure and HR responsiveness in 139 (70 Somali; age: 29±10 years, 69 White; age: 31±9 years) participants. Supine SAP, DAP, and HR were measured after at least five minutes of supine rest, and again after one minute of standing. SAP, DAP, and HR change was compared between groups.

Results

ΔSAP and ΔDAP were similar between groups (race × sex: p>0.05). However, HR responsiveness to orthostasis varied between race and sex comparisons (race×sex: p=0.011). Somali females exhibited an augmented HR response to orthostasis compared to White females (Δ19±13 vs. 11±9 beats/min, p=0.005) and Somali males (Δ19±13 vs. 12±9 beats/min, p=0.020).

Conclusion

ΔHR to standing is augmented in young female Somali Americans. These findings highlight an early potential impairment in hemodynamic regulation that may heighten future cardiovascular risk. Further work is warranted to identify the potential autonomic nervous system underpinnings that may contribute to potentiated orthostatic responses and cardiovascular risk in Somali American females.

Clinical Trial Registration

www.clinicaltrials.gov; unique identifier, NCT04124848; NCT05411029; NCT03308578.

Sway detection in hypertension as a novel tool to anticipate risk and morbidity due to postural instability

Objectives:

Hypertension contributes substantially to poor physical function and autonomic imbalance. It may cause instability in posture that limits daily activities and can lead to devastating falls. Centre of pressure (CoP) is a commonly used index of postural stability while standing and is a measure of the activity of the motor system, which may be altered in hypertension. It is also observed that the fall incidence is higher in women than men, which may be due to postural instability. The pilot study was conducted to see whether the presence of essential hypertension further contributes to postural instability in women and compared with age-matched normotensive controls.

Materials and Methods:

Sixteen hypertensive women on regular treatment for hypertension and 16 age-matched normotensive women with a mean age of 51.9 ± 9.1 years were included in the study. The WII balance board was used to measure the CoP and displacement to sway. PowerLab 8/35 (AD instruments) with LabChart software was used to measure the parameters.

Results:

Displacement of CoP in the mediolateral direction was studied in the trials. The CoP was measured in eyes closed and eyes open conditions and was displaced in both groups, with significant displacement in hypertensive women. With voluntary sway to their right and left sides, hypertensive women have shown significantly less sway displacement compared to normotensive women. In hypertensives, during right sway, the error of correction was 13%. During left sway, overcorrection was high in both hypertensive and normotensive.

Conclusion:

Postural instability is observed in hypertension, and posturography can be used as a routine screening tool to predict postural instability in hypertensives. Balance training exercise biofeedback protocols and the use of sensory augmentation devices may prove to be useful in improving postural stability.

Influence of Night Shift Work on Heart Rate Variability in an Age- and Gender-Matched Study Group

Regular and long-term shift work is associated with a number of chronic diseases. There is some evidence that shift work also has an influence on the autonomous nervous system. Studies that have examined the effect of shift work on heart rate variability (HRV) have not taken into account age and gender. Therefore, the aim of this study was to investigate the influence of night shift based on 24 h long-term analyses carried out on non-night shift days with a matched control group for age and gender. In total, 172 (128 male, 44 female) healthy shift night workers were compared with subjects from a non-night shift worker group at a ratio of 1:1, forming matched pairs based on the subjects' sex and age. HRV parameters were analyzed based on 24 h ECG recording. An analysis of the HRV parameters showed only a small difference but without statistical significance between the two groups with regard to all of the HRV parameters examined (SDNN, RMSSD, NN50, pNN50, VLF, LF, HF, LF/HF, DFA1, and DFA2). An analysis of the subgroup of subjects who had only worked night shifts for a minimum of 10 or 20 years, with the respective pairs matched by age and gender, did not reveal any significant differences between the HRV parameters of employees working night shifts and those not working night shifts. Taking into account qualitative aspects of HRV analysis, this study was thus able to show that working night shifts for many years may not have as big an influence on HRV as had been assumed so far.

Impact of Kangaroo mother care on autonomic cardiovascular control in foetal-growth-restricted preterm infants

BACKGROUND

Kangaroo mother care (KMC) is WHO-recommended for low-birth-weight infants, yet its impact on autonomic cardiovascular control in preterm foetal growth-restricted (FGR) infants remains unclear. We hypothesised that KMC would promote autonomic cardiovascular control, benefiting preterm FGR infants with reduced baseline autonomic function compared to appropriate for gestational age (AGA) infants.

METHODS

Autonomic control was assessed via heart rate variability (HRV) in low frequency (LF) and high frequency (HF) bands using spectral analysis. Preterm FGR (n = 22) and AGA (n = 20) infants were assessed for 30-min before and 60-min during KMC. Comparisons were made between FGR and AGA infants; and between infants with baseline HRV below and above median.

RESULTS

Overall, no significant HRV changes were observed during KMC for FGR or AGA infants compared to baselines. Infants with low baseline HRV LF showed increased HRV during KMC (p = 0.02 and 0.05 for the entire group and FGR group, respectively). This effect was absent in the AGA group regardless of baseline HRV. Infants with high baseline HRV had decreased HRV during KMC.

CONCLUSIONS

Infants with low baseline HRV, suggesting reduced autonomic control, are more likely to benefit from KMC with increased HRV. Further, this effect is stronger in FGR than AGA infants.

IMPACT

Kangaroo mother care (KMC) is WHO-recommended for low-birth-weight infants, yet its impact on autonomic cardiovascular control in preterm foetal growth-restricted (FGR) infants is unclear. Preterm infants with low baseline heart rate variability (HRV) are more likely to benefit from KMC and increase their HRV suggesting improved autonomic control. This effect is stronger in preterm FGR infants than those with appropriate growth for age.

Update: factors influencing heart rate variability-a narrative review

Objective

Heart rate variability (HRV) is an important non-invasive marker for the assessment of an organism's autonomic physiological regulatory pathways. Lower HRV has been shown to correlate with increased mortality. HRV is influenced by various factors or diseases. The aim of this narrative review is to describe the current state of knowledge on factors influencing HRV and their significance for interpretation.

Methods

The narrative review only included reviews, meta-analyses, and cohort studies which were published until 2021. HRV confounders were grouped into four categories (non-influenceable physiological factors, diseases, influenceable lifestyle factors and external factors).

Results

The review found that HRV was decreased not only in non-influenceable physiological factors (e.g., age, gender, ethnicity) but also in connection with various number of acute and chronic diseases (e.g., psychiatric diseases, myocardial infarction, heart failure), influenceable lifestyle factors (e.g., alcohol abuse, overweight, physical activity), and external factors (e.g., heat, noise, shift work, harmful- and hazardous substances).

Conclusion

In order to improve the quality of HRV studies and to ensure accurate interpretation, it is recommended that confounders be taken into account in future diagnostic measurements or measurements in the workplace (e.g., as part of health promotion measures) in order to counteract data bias.

Isometric Exercise Training and Arterial Hypertension: An Updated Review

Hypertension is recognised as a leading attributable risk factor for cardiovascular disease and premature mortality. Global initiatives towards the prevention and treatment of arterial hypertension are centred around non-pharmacological lifestyle modification. Exercise recommendations differ between professional and scientific organisations, but are generally unanimous on the primary role of traditional aerobic and dynamic resistance exercise. In recent years, isometric exercise training (IET) has emerged as an effective novel exercise intervention with consistent evidence of reductions in blood pressure (BP) superior to that reported from traditional guideline-recommended exercise modes. Despite a wealth of emerging new data and endorsement by select governing bodies, IET remains underutilised and is not widely prescribed in clinical practice. This expert-informed review critically examines the role of IET as a potential adjuvant tool in the future clinical management of BP. We explore the efficacy, prescription protocols, evidence quality and certainty, acute cardiovascular stimulus, and physiological mechanisms underpinning its anti-hypertensive effects. We end the review with take-home suggestions regarding the direction of future IET research.

Guideline for the application of heart rate and heart rate variability in occupational medicine and occupational health science

This updated guideline replaces the "Guideline for the application of heart rate and heart rate variability in occupational medicine and occupational health science" first published in 2014. Based on the older version of the guideline, the authors have reviewed and evaluated the findings on the use of heart rate (HR) and heart rate variability (HRV) that have been published in the meantime and incorporated them into a new version of this guideline.This guideline was developed for application in clinical practice and research purposes in the fields of occupational medicine and occupational science to complement evaluation procedures with respect to exposure and risk assessment at the workplace by the use of objective physiological workload indicators. In addition, HRV is also suitable for assessing the state of health and for monitoring the progress of illnesses and preventive medical measures. It gives an overview of factors influencing the regulation of the HR and HRV at rest and during work. It further illustrates methods for measuring and analyzing these parameters under standardized laboratory and real workload conditions, areas of application as well as the quality control procedures to be followed during the recording and evaluation of HR and HRV.

Automatic identification of hypertension and assessment of its secondary effects using artificial intelligence: A systematic review (2013-2023)

Artificial Intelligence (AI) techniques are increasingly used in computer-aided diagnostic tools in medicine. These techniques can also help to identify Hypertension (HTN) in its early stage, as it is a global health issue. Automated HTN detection uses socio-demographic, clinical data, and physiological signals. Additionally, signs of secondary HTN can also be identified using various imaging modalities. This systematic review examines related work on automated HTN detection. We identify datasets, techniques, and classifiers used to develop AI models from clinical data, physiological signals, and fused data (a combination of both). Image-based models for assessing secondary HTN are also reviewed. The majority of the studies have primarily utilized single-modality approaches, such as biological signals (e.g., electrocardiography, photoplethysmography), and medical imaging (e.g., magnetic resonance angiography, ultrasound). Surprisingly, only a small portion of the studies (22 out of 122) utilized a multi-modal fusion approach combining data from different sources. Even fewer investigated integrating clinical data, physiological signals, and medical imaging to understand the intricate relationships between these factors. Future research directions are discussed that could build better healthcare systems for early HTN detection through more integrated modeling of multi-modal data sources.

Dose-effect of exercise intervention on heart rate variability of acclimatized young male lowlanders at 3,680 m

This study investigated whether exercise could improve the reduced HRV in an environment of high altitude. A total of 97 young, healthy male lowlanders living at 3,680 m for >1 year were recruited. They were randomized into four groups, of which three performed-low-, moderate-, and high-intensity (LI, MI, HI) aerobic exercise for 4 weeks, respectively. The remaining was the control group (CG) receiving no intervention. For HI, compared to other groups, heart rate (p = 0.002) was significantly decreased, while standard deviation of RR intervals (p < 0.001), SD2 of Poincaré plot (p = 0.046) and the number of successive RR interval pairs that differ by > 50 ms divided by total number of RR (p = 0.032), were significantly increased after intervention. For MI, significantly increase of trigonometric interpolation in NN interval (p = 0.016) was observed after exercise. Further, a decrease in systolic blood pressure (SBP) after high-intensity exercise was found significantly associated with an increase in SD2 (r = - 0.428, p = 0.042). These results indicated that there was a dose effect of different intensities of aerobic exercise on the HRV of acclimatized lowlanders. Moderate and high-intensity aerobic exercise would change the status of the autonomic nervous system (ANS) and decrease the blood pressure of acclimatized lowlanders exposed to high altitude.

Effects of continuous supplementation of Acanthopanax senticosus Harms on the cardiac autonomic function of community-dwelling elderly individuals during resting and standing tests: a randomized controlled trial

Background

Cardiac autonomic function (CAF) decreases with aging, and Acanthopanax senticosus Harms (ASH) consumption reportedly induces anti-stress effects. This study aimed to assess the effect of continuous supplementation of ASH on CAF during resting and standing tests in the elderly population.

Methods

This double-blind, randomized controlled trial was conducted in the morning in a laboratory setting and was carried out between June 2017 and July 2017 at Kambaikan, Doshisha University (Karasuma-higashi-iru, Imadegawa-dori, Kamigyo-ku, Kyoto 602-8580, Japan). In total, 28 community-dwelling elderly individuals (mean ± standard deviation = 72.5 ± 4.5 years) were included. Each subject was instructed to consume ASH or placebo supplements twice daily for 4 weeks. An autonomic reflex orthostatic tolerance recorder was used to measure CAF in pre- and post-intervention phases. Parameters were measured in a seated position and included coefficient of variation of R-R intervals (CVRR), low frequency (LF), high frequency (HF), LF/HF ratio, blood pressure, and heart rate (HR). Changes in each parameter were evaluated before and after standing. All parameters were defined as the difference between the mean value obtained in a standing position for 2 min and that obtained in a 2-min seated position.

Results

A two-way analysis of variance revealed a significant group-time interaction effect on CVRR, HF, and ΔLF/HF ratio. Following the intervention, CVRR, HF, LF/HF ratio, systolic blood pressure (SBP), HR, ΔLF/HF ratio, ΔSBP, and ΔHR improved significantly in the ASH group only.

Conclusions

Four-week supplementation of ASH improved CAF in community-dwelling elderly individuals during resting and standing tests.

Clinical Trial Registration

https://center6.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000031218, UMIN Clinical Trials Registry (UMIN000027251).

Resistance exercise lowers blood pressure and improves vascular endothelial function in individuals with elevated blood pressure or stage-1 hypertension

Lifestyle modifications are the first-line treatment recommendation for elevated blood pressure (BP) or stage-1 hypertension (E/S1H) and include resistance exercise training (RET). The purpose of the current study was to examine the effect of a 9-wk RET intervention in line with the current exercise guidelines for individuals with E/S1H on resting peripheral and central BP, vascular endothelial function, central arterial stiffness, autonomic function, and inflammation in middle-aged and older adults (MA/O) with untreated E/S1H. Twenty-six MA/O adults (54 ± 6 yr; 16 females/10 males) with E/S1H engaged in either 9 wk of 3 days/wk RET (n = 13) or a nonexercise control (Con; n = 13). Pre- and postintervention measures included peripheral and central systolic (SBP and cSBP) and diastolic BP (DBP and cDBP), flow-mediated dilation (FMD), carotid-femoral pulse wave velocity (cfPWV), cardiovagal baroreflex sensitivity (BRS), cardiac output (CO), total peripheral resistance (TPR), heart rate variability (HRV), and C-reactive protein (CRP). RET caused significant reductions in SBP {mean change ± 95% CI = [-7.9 (-12.1, -3.6) mmHg; P < 0.001]}, cSBP [6.8 (-10.8, -2.7) mmHg; P < 0.001)], DBP [4.8 (-10.3, -1.2) mmHg; P < 0.001], and cDBP [-5.1 (-8.9, -1.3) mmHg; P < 0.001]; increases in FMD [+2.37 (0.61, 4.14)%; P = 0.004] and CO [+1.21 (0.26, 2.15) L/min; P = 0.006]; and a reduction in TPR [-398 (-778, -19) mmHg·s/L; P = 0.028]. RET had no effect on cfPWV, BRS, HRV, or CRP relative to Con (P ≥ 0.20). These data suggest that RET reduces BP in MA/O adults with E/S1H alongside increased peripheral vascular function and decreased TPR without affecting cardiovagal function or central arterial stiffness.NEW & NOTEWORTHY This is among the first studies to investigate the effects of chronic resistance exercise training on blood pressure (BP) and putative BP regulating mechanisms in middle-aged and older adults with untreated elevated BP or stage-1 hypertension in a randomized, nonexercise-controlled trial. Nine weeks of resistance exercise training elicits 4- to 8-mmHg improvements in systolic and diastolic BP alongside improvements in vascular endothelial function and total peripheral resistance without influencing central arterial stiffness or cardiovagal function.

Cardiovascular diseases across OSA phenotypes: A retrospective cohort study

Background

Despite the considerable knowledge of Obstructive Sleep Apnea (OSA) implications for cardiac diseases, the evidence regarding cardiovascular complications across OSA phenotypes including Rapid Eye Movement OSA (REM-OSA) and Positional OSA (POSA) is limited. In this study, we aimed to evaluate the risk of cardiovascular diseases development and progression among patients with REM-OSA and POSA.

Methods

Based on a retrospective cohort analysis, we included polysomnography studies done in the sleep lab at the Jordan University Hospital. Regarding cardiovascular diseases, primary outcomes were Heart Failure, and 1-years Major Adverse Cardiac Events while secondary outcomes were atrial fibrillation, pulmonary hypertension, other arrhythmia, metabolic profile, and echocardiographic measurements of the heart.

Results

The total number of the included patients was 1,026 patients. POSA group had significantly lower percentage of patients with hypertension (P-value = 0.004). Additionally, systolic blood pressure and HbA1c were significantly lower among patients with POSA compared to the NPOSA group (P-value<0.050). Left ventricular end diastolic dimension was significantly higher among patients with POSA while ejection fraction was significantly lower (P-value<0.050). Patients with diabetes and mean HbA1c were significantly lower among patients with REM-OSA compared to patients with NREM-OSA (P-value = 0.015, P-value = 0.046). Multivariate regression analysis revealed that after adjusting for age, gender and preexisting comorbidities, POSA was significantly associated with lower ejection fraction and higher left ventricular diastolic diameter.

Conclusion

In conclusion, our findings indicate that POSA might be associated with huge and clinically significant heart strain and poor cardiac functions, yet it might not have a clinically significant atherogenic effect. This study should guide clinicians to identify OSA phenotypes to imply the best treatment plan to reduce its detrimental impact on cardiac muscle.

Autonomic regulation in different hypertensive phenotypes - the HELIUS study

Background: Hypertension can be classified into different phenotypes based on systolic and diastolic blood pressure (BP) that carry a different prognosis and may therefore be differently associated with sympathetic activity. We assessed the association between cardiac autonomic function determined from continuous finger BP recordings and hypertensive phenotypes. Methods: We included 10,221 individuals aged between 18-70 years from the multi-ethnic HELIUS study. Finger BP was recorded continuously for 3-5 minutes from which cross-correlation baroreflex sensitivity (xBRS) and heart rate variability (HRV) were determined. Hypertension was classified into isolated systolic (ISH; ≥140/<90), diastolic (IDH; <140/≥90) and combined systolic and diastolic hypertension (SDH; ≥140/≥90). Differences were assessed after stratification by age (younger: ≤40, older: >40 years) and sex, using regression with correction for relevant covariates. For xBRS, values were log-transformed. Results: In younger adults with ISH, xBRS was comparable to normotensive individuals in men (ratio 0.92; 95%CI 0.84-1.01) and women (1.00; 95%CI 0.84-1.20), while xBRS was significantly lower in IDH and SDH (ratios between 0.67 and 0.80). In older adults, all hypertensive phenotypes had significantly lower xBRS compared to normotensives. We found a similar pattern for HRV in men, while in women HRV did not differ between phenotypes. Conclusions: In younger men and women ISH is not associated with a shift towards increased sympathetic control, while IDH and SDH in younger and all hypertensive phenotypes in older participants were associated with increased sympathetic control. This suggests that alterations in autonomic regulation could be a contributing factor to known prognostic disparities between hypertensive phenotypes.

Validity and Efficacy of the Elite HRV Smartphone Application during Slow-Paced Breathing

Slow-paced breathing is a clinical intervention used to increase heart rate variability (HRV). The practice is made more accessible via cost-free smartphone applications like Elite HRV. We investigated whether Elite HRV can accurately measure and augment HRV via its slow-paced breathing feature. Twenty young adults completed one counterbalanced cross-over protocol involving 10 min each of supine spontaneous (SPONT) and paced (PACED; 6 breaths·min-1) breathing while RR intervals were simultaneously recorded via a Polar H10 paired with Elite HRV and reference electrocardiography (ECG). Individual differences in HRV between devices were predominately skewed, reflecting a tendency for Elite HRV to underestimate ECG-derived values. Skewness was typically driven by a limited number of outliers as median bias values were ≤1.3 ms and relative agreement was ≥very large for time-domain parameters. Despite no significant bias and ≥large relative agreement for frequency-domain parameters, limits of agreement (LOAs) were excessively wide and tended to be wider during PACED for all HRV parameters. PACED significantly increased low-frequency power (LF) for Elite HRV and ECG, and between-condition differences showed very large relative agreement. Elite HRV-guided slow-paced breathing effectively increased LF values, but it demonstrated greater precision during SPONT and in computing time-domain HRV.

Cardiac autonomic modulation in individuals with controlled and uncomplicated hypertension during exercise-heat stress

TAKE-HOME MESSAGE

During short bouts of light-to-vigorous exercise in the heat, controlled and uncomplicated hypertension did not significantly modulate HRV in physically active individuals. These findings can be used to refine guidance on use of exercise for hypertension management in the heat.

Heart rate variability and cardiovascular risk factors in patients with rheumatoid arthritis: A longitudinal study

BACKGROUND

It is established that the risk of cardiovascular disease (CVD) is increased in patients with Rheumatoid Arthritis (RA). Heart rate variability (HRV) is a method for evaluating the activity in the cardiac autonomic nervous system. Our aim was to assess the longitudinal development of HRV in patients with RA and compare with healthy controls. Furthermore, we wanted to investigate associations between HRV, inflammatory disease activity and cardiovascular complications in patients with RA over time.

METHOD

HRV was assessed with frequency-domain analysis at baseline and after five years in 50 patients with early RA, all being younger than 60 years. HRV indices were age-adjusted based on the estimated age-dependency in 100 age and sex matched healthy controls. Additionally, clinical data including serological markers, disease activity, and blood pressure were collected from the patients. Eleven years after inclusion CVD was assessed.

RESULTS

At baseline, patients with RA presented with lower HRV compared to controls during deep breathing (6 breaths/min), paced normal breathing (12 breaths/min) and after passive tilt to the upright position. No significant change in HRV was observed at the five-year follow-up. A significant negative correlation was found between HRV parameters and systolic blood pressure (SBP) at baseline. A significant positive correlation was found between heart rate and inflammatory markers at baseline but not after five years. Nine patients had developed CVD after 11 years, but no significant association was found with baseline HRV data.

CONCLUSION

This study showed that patients with RA have autonomic imbalance both at an early stage of the disease and after five years, despite anti-rheumatic medication, but no correlation between HRV and inflammation markers were observed. Reduced HRV was also significantly negatively correlated with increased SBP. Hypertension is a common finding in patients with RA. Thus, significant decline of HRV could be a useful early marker for development of hypertension in patients with RA.

Cardiac Autonomic Function and Functional Capacity in Post-COVID-19 Individuals with Systemic Arterial Hypertension

Individuals diagnosed with systemic arterial hypertension (SAH) are considered risk groups for COVID-19 severity. This study assessed differences in cardiac autonomic function (CAF) and functional capacity (FC) in SAH individuals without COVID-19 infection compared to SAH individuals post-COVID-19. Participants comprised 40 SAH individuals aged 31 to 80 years old, grouped as SAH with COVID-19 (G1; n = 21) and SAH without COVID-19 (G2; n = 19). CAF was assessed via heart rate variability (HRV), measuring R-R intervals during a 10-min supine period. Four HRV indices were analyzed through symbolic analysis: 0V%, 1V%, 2LV%, and 2UV%. FC assessment was performed by a 6-min walk test (6MWT). G1 and G2 showed no significant differences in terms of age, anthropometric parameters, clinical presentation, and medication use. G2 exhibited superior 6MWT performance, covering more distance (522 ± 78 vs. 465 ± 59 m, p < 0.05). Specifically, G2 demonstrated a moderate positive correlation between 6MWT and the 2LV% index (r = 0.58; p < 0.05). Shorter walking distances were observed during 6MWT in SAH individuals post-COVID-19. However, the study did not find impaired cardiac autonomic function in SAH individuals post-COVID-19 compared to those without. This suggests that while COVID-19 impacted FC, CAF remained relatively stable in this population.

Autonomic control of ventricular function in health and disease: current state of the art

PURPOSE

Cardiac autonomic dysfunction is one of the main pillars of cardiovascular pathophysiology. The purpose of this review is to provide an overview of the current state of the art on the pathological remodeling that occurs within the autonomic nervous system with cardiac injury and available neuromodulatory therapies for autonomic dysfunction in heart failure.

METHODS

Data from peer-reviewed publications on autonomic function in health and after cardiac injury are reviewed. The role of and evidence behind various neuromodulatory therapies both in preclinical investigation and in-use in clinical practice are summarized.

RESULTS

A harmonic interplay between the heart and the autonomic nervous system exists at multiple levels of the neuraxis. This interplay becomes disrupted in the setting of cardiovascular disease, resulting in pathological changes at multiple levels, from subcellular cardiac signaling of neurotransmitters to extra-cardiac, extra-thoracic remodeling. The subsequent detrimental cycle of sympathovagal imbalance, characterized by sympathoexcitation and parasympathetic withdrawal, predisposes to ventricular arrhythmias, progression of heart failure, and cardiac mortality. Knowledge on the etiology and pathophysiology of this condition has increased exponentially over the past few decades, resulting in a number of different neuromodulatory approaches. However, significant knowledge gaps in both sympathetic and parasympathetic interactions and causal factors that mediate progressive sympathoexcitation and parasympathetic dysfunction remain.

CONCLUSIONS

Although our understanding of autonomic imbalance in cardiovascular diseases has significantly increased, specific, pivotal mediators of this imbalance and the recognition and implementation of available autonomic parameters and neuromodulatory therapies are still lagging.

Impact of virtual adjunctive cognitive remediation therapy on cognitive flexibility and treatment outcomes in comorbid anorexia nervosa and exercise dependence as quantified using novel biomarkers: A stage 1 registered report

OBJECTIVE

Anorexia nervosa (AN) is associated with significant individual mental and physical suffering and public health burden and fewer than half of patients recover fully with current treatments. Comorbid exercise dependence (ExD) is common in AN and associated with significantly worse symptom severity and treatment outcomes. Research points to cognitive inflexibility as a prominent executive function inefficiency and transdiagnostic etiologic and maintaining mechanism linking AN and ExD. This study will evaluate the initial efficacy of adjunctive Cognitive Remediation Therapy (CRT), which has been shown to produce cognitive improvements in adults with AN, in targeting cognitive inflexibility in individuals with comorbid AN and ExD. As an exploratory aim, this study also addresses the current lack of quick and cost-effective assessments of cognitive flexibility by establishing the utility of two proposed biomarkers, heart rate variability and salivary oxytocin.

METHOD

We will conduct a single-group, within-subjects trial of an established CRT protocol delivered remotely as an adjunct to inpatient or intensive outpatient treatment as usual (TAU) to adult patients (n = 42) with comorbid AN and ExD. Assessments, including self-report, neuropsychological, and biomarker measurements, will occur at three time points.

RESULTS

We expect CRT to increase cognitive flexibility transdiagnostically and consequently, along with TAU, positively impact AN and ExD compulsivity and symptom severity, including weight gain.

DISCUSSION

Findings will inform the development of more effective integrative interventions for AN and ExD targeting shared mechanisms and facilitate the routine assessment of cognitive flexibility as a transdiagnostic risk and maintaining factor across psychopathologies in clinical and research settings.

PUBLIC SIGNIFICANCE

Patients with anorexia nervosa often engage in excessive exercise, leading to harmful outcomes, including increased suicidal behavior. This study examines the preliminary efficacy of an intervention that fosters flexible and holistic thinking in patients with problematic eating and exercise to, along with routine treatment, decrease harmful exercise symptoms. This study also examines new biological markers of the inflexible thinking style thought to be characteristic of anorexia nervosa and exercise dependence.

Effects of Three-Hour Wearing Personal Protective Equipment on Heart Rate Variability in Healthcare Workers for the Treatment of COVID-19 Patients

Background

Personal protective equipment (PPE), an essential shield to protect healthcare workers (HCWs) during the COVID-19 pandemic, has been reported to affect their heart rate variability (HRV).

Objective

To investigate the changes of very short-term heart rate variability in HCWs after three hours of wearing PPE to treat COVID-19 patients at different working times and intensities, and related factors.

Methods

Sixty-five healthy HCWs were enrolled at the Number 2 Infectious Field Hospital (formed by Military Hospital 103), Vietnam. Two-minute 12-lead electrocardiograms were recorded before wearing and after removing PPE.

Results

After three hours of wearing PPE, the mean heart rate of HCWs increased (p = 0.048) meanwhile, the oxygen saturation decreased significantly (p = 0.035). Standard deviation of all normal to normal intervals (SDNN), mean intervals RR (mean NN), and root mean square successive difference (rMSSD) after wearing PPE was also reduced significantly. SDNN, Mean NN, and rMSSD decreased as the working intensity increased (as in mild, moderate, and severe patient departments). In univariate regression analysis, logSDNN, logmean NN and logrMSSD were positively correlated with SpO2 and QT interval (r = 0.14, r = 0.31, r = 0.25; r = 0.39, r = 0.77, r = 0.73, respectively) and were negatively correlated with ambient temperature inside PPE (r = -0.41, r = -0.405, r = -0.25, respectively) while logmean NN and log rMSSD were negatively correlated with diastolic blood pressure (r = -0.43, r = -0.39, respectively). In multivariable regression analysis, logSDNN and logmean NN were negatively correlated to ambient temperature inside PPE (r = -0.34, r = -0.18, respectively).

Conclusion

Time-domain heart rate variability decreased after wearing PPE. Time-domain HRV parameters were related to ambient temperature inside PPE, diastolic blood pressure, QT interval, and SpO2.

Effects of Preoperative Sarcopenia-Related Parameters on Cardiac Autonomic Function in Women with Obesity Following Bariatric Surgery: A One-Year Prospective Study

OBJECTIVES

Investigate changes in blood pressure (BP) and heart rate variability (HRV) in women with and without sarcopenia-related parameters who underwent bariatric surgery (BS) during a one-year follow-up.

SUBJECTS AND METHODS

Women were separated into obesity (OB, n = 20) and women with obesity displaying sarcopenia-related parameters (SOP, n = 14) and evaluated before BS and 3, 6, and 12 months after BS. SOP was defined as low handgrip strength (HS) and/or low appendicular skeletal mass adjusted for weight (ASM/wt × 100, %) in the lowest quartile of the sample. ASM/wt × 100, % and HS were significantly lower in SOP than OB over a one-year follow-up of BS (p < 0.05).

RESULTS

There was a reduction in diastolic BP, heart rate (HR), SDHR, LF, and the LF/HF ratio (p < 0.05) and an increase in the HF band in both groups during the follow-up period (p < 0.05). SOP women had reduced root mean square differences of successive RR intervals (RMSSD) and HF band and an increased LF band and SD2/SD1 ratio compared to the OB group during the one-year follow-up (p < 0.05). ASM/wt × 100, % was negatively associated with the LF band (r = -0.24, p = 0.00) and positively associated with the HF band (r = 0.22, p = 0.01). Conversely, HS had no association with LF (r = -0.14, p = 0.09) and HF (r = 0.11, p = 0.19). ASM/wt × 100, % and HS were negatively associated with the LF/HF ratio (p < 0.05).

CONCLUSIONS

Women who underwent BS had an improved HRV over a one-year follow-up. However, the improvement in HRV variables was less pronounced in women with low muscle mass and/or HS during the follow-up period.

Heart Rate Variability in Normotensive and Hypertensive Adults After a Year of Receiving Oxford/AstraZeneca COVID-19 Vaccine: A Cross-Sectional Observational Study

Background and aim Heart rate variability (HRV) helps in assessing the autonomic nervous system's function, which has been implicated in cardiovascular disease risk. HRV has been found to be deranged in hypertension. In addition, studies have shown that COVID-19 infection and vaccination can affect HRV. However, the long-term effect of HRV on hypertension has not been explored after COVID-19 vaccination. The objective of this study was to observe the HRV in hypertensive adults after one year of receiving the Oxford/AstraZeneca COVID-19 vaccine and to compare it with normotensive adults. Methods The study included 105 normotensives (blood pressure below 120/80 mmHg) and 75 hypertensive participants who had received the Oxford/AstraZeneca COVID-19 vaccine one year prior. HRV was measured using the PowerLab system (ADInstruments) with the participants in a sitting posture. The HRV parameters assessed included the time domain, frequency domain, and nonlinear measures. Data were presented in descriptive and inferential statistical terms, and the parameters of two groups of individuals were compared by either an unpaired t-test or the Mann-Whitney U test. Results A total of 105 normotensive participants with a mean age of 42.51 ± 9.28 years and 75 hypertensive participants with a mean age of 44.24 ± 10.19 years comprised the sample (p=0.24). Normotensive individuals had a higher standard deviation of RR intervals, a higher coefficient of variation of RR intervals, a higher standard deviation of heart rate, and a higher percentage of successive differences in RR intervals in the time domain. They also had higher values of very low-frequency power, low-frequency (LF) power, and high-frequency (HF) power in the frequency domain. The LF/HF ratio was not significantly different between the two groups. In nonlinear analysis, SD2, a measure of long-term heart rate variability, was higher in normotensive individuals. Conclusion The Oxford/AstraZeneca COVID-19 vaccine did not have a significant effect on HRV parameters in normotensive and hypertensive adults one year after vaccination. However, changes in HRV parameters were observed between supine and standing positions, suggesting the importance of postural changes in HRV assessment.

Comparison of heart rate variability in normotensive and hypertensive Indian adults

Autonomic imbalance is seen in hypertensive. This study was designed to compare heart rate variability in normotensive and hypertensive Indian adults. HRV records beat to beat variation in R-R intervals in milliseconds in electrocardiogram. Lead II ECG was recorded and a 5 minutes' stationary, artifacts free recording was selected for data analysis. HRV measures like total power was significantly less in hypertensive (303.37 ± 438.1) as compared to normotensive (534.16 ± 818.41). Standard deviation of normal-to-normal RR intervals was significantly reduced in hypertensive. A significant reduction of HRV was seen in hypertensive as compared to normotensive.

The Role of Heart Rate Variability (HRV) in Different Hypertensive Syndromes

Cardiac innervation by the parasympathetic nervous system (PNS) and the sympathetic nervous system (SNS) modulates the heart rate (HR) (chronotropic activity) and the contraction of the cardiac muscle (inotropic activity). The peripheral vasculature is controlled only by the SNS, which is responsible for peripheral vascular resistance. This also mediates the baroreceptor reflex (BR), which in turn mediates blood pressure (BP). Hypertension (HTN) and the autonomic nervous system (ANS) are closely related, such that derangements can lead to vasomotor impairments and several comorbidities, including obesity, hypertension, resistant hypertension, and chronic kidney disease. Autonomic dysfunction is also associated with functional and structural changes in target organs (heart, brain, kidneys, and blood vessels), increasing cardiovascular risk. Heart rate variability (HRV) is a method of assessing cardiac autonomic modulation. This tool has been used for clinical evaluation and to address the effect of therapeutic interventions. The present review aims (a) to approach the heart rate (HR) as a CV risk factor in hypertensive patients; (b) to analyze the heart rate variability (HRV) as a "tool" to estimate the individual risk stratum for Pre-HTN (P-HTN), Controlled-HTN (C-HTN), Resistant and Refractory HTN (R-HTN and Rf-HTN, respectively), and hypertensive patients with chronic renal disease (HTN+CKD).

Associations between Autonomic Function and Cognitive Performance among Patients with Cerebral Small Vessel Disease

Data linking heart rate variability (HRV) and cognitive status remains controversial and scarce, particularly in cerebral small vessel disease (CSVD) patients. Whether the association between HRV and cognitive performance exists in CSVD patients is unclear. Hence, we aimed to investigate the association between HRV and cognitive performance in patients with CSVD. This cross-sectional study was conducted among 117 CSVD patients. All patients underwent HRV assessment and global cognitive evaluation by the Mini-Mental-State Examination (MMSE) and Montreal Cognitive Assessment (MoCA). Multivariable analyses were performed to evaluate the association between HRV and cognitive status. The mean age of study population was 59.5 ± 11.8 years and 39.3% were female. After adjusting for confounding factors, a higher high frequency (HF) norm was independently associated with better MMSE scores (β = 0.051; 95% confidence interval (CI): 0.012~0.090; p = 0.011) and MoCA scores (β = 0.061; 95% CI: 0.017~0.105; p = 0.007), while a higher low frequency (LF)/HF ratio was independently associated with worse MMSE scores (β = -0.492; 95% CI: -0.893~-0.092; p = 0.017) and MoCA scores (β = -0.691; 95% CI: -1.134~-0.248; p = 0.003). The HF norm was positively associated with global cognitive performance, whereas the LF/HF ratio was negatively associated with global cognitive performance among CSVD patients. Further study of the relationship between autonomic function and cognitive performance is warranted.

Enhancing Inhibitory Control in Older Adults: A Biofeedback Study

Multidomain interventions based on bio-/neurofeedback have proven useful in improving executive functions. The present study aimed to explore the potential efficacy and feasibility of an intervention that combined Heart Rate Variability Biofeedback (HRV-BF) and Near Infrared Hemoencephalography Neurofeedback (nirHEG-NF) on inhibitory control (IC) of healthy older adults. Thirty-four participants were randomly assigned to two groups: the biofeedback group (received a 10-week combined intervention of HRV-BF and nirHEG-NF) and the active control group (received a similar protocol without real-time biofeedback). Besides cognitive outcomes, the study examined pre- and post-changes in autonomic regulation and prefrontal blood oxygenation at rest and during training. Results revealed training-induced inhibitory control gains in one of the two interference tasks, whereas no effect was found on response inhibition. After the intervention, HRV increased in participants with the lowest levels of HRV at baseline. Although older adults increased blood oxygenation during training, no significant pre- and post-changes were found in blood flow oxygenation. These findings not only suggest that HRV-BF and nirHEG-NF potentially improve performance in certain subcomponents of inhibition (i.e., interference vs. response inhibition), but it may also be beneficial for parasympathetic activity in participants with low HRV and for increasing blood flow oxygenation on prefrontal areas during training.

Automated analysis of finger blood pressure recordings provides insight in determinants of baroreflex sensitivity and heart rate variability-the HELIUS study

Sympathovagal balance is important in the pathogenesis of hypertension and independently associated with mortality. We evaluated the value of automated analysis of cross-correlation baroreflex sensitivity (xBRS) and heart rate variability (HRV) and its relationship with clinical covariates in 13,326 participants from the multi-ethnic HELIUS study. Finger blood pressure (BP) was continuously recorded, from which xBRS, standard deviation of normal-to-normal intervals (SDNN), and squared root of mean squared successive difference between normal-to-normal intervals (RMSDD) were determined. A subset of 3356 recordings > 300 s was used to derive the minimally required duration by comparing shortened to complete recordings, defined as intraclass correlation (ICC) > 0.90. For xBRS and SDNN, 120 s and 180 s were required (ICC 0.93); for RMSDD, 60 s (ICC 0.94) was sufficient. We included 10,252 participants (median age 46 years, 54% women) with a recording > 180 s for the regression. xBRS, SDNN, and RMSDD decreased linearly up to 50 years of age. For xBRS, there was a signification interaction with sex, with for every 10 years a decrease of 4.3 ms/mmHg (95%CI 4.0-4.6) for men and 5.9 ms/mmHg (95%CI 5.6-6.1) for women. Using splines, we observed sex-dependent nonlinearities in the relation with BP, waist-to-hip-ratio, and body mass index. Future studies can help unravel the dynamics of these relations and assess their predictive value. Panel 1 depicts automatic analysis and filtering of finger BP recordings, panel 2 depicts computation of xBRS from interpolated beat to beat data of systolic BP and interbeat interval, and (IBI) SDNN and RMSDD are computed directly from the filtered IBI dataset. Panel 3 depicts the results of large-scale analysis and relation of xBRS with age, sex, blood pressure and body mass index.

Cardiopulmonary benefits of respirator intervention against near road ambient particulate matters in healthy young adults: A randomized, blinded, crossover, multi-city study

Wearing a respirator is generally the most convenient individual intervention against ambient particulate matter (PM), and therefore there has been considerable research into its effectiveness. However, the effects of respirator intervention under different PM concentration settings have been insufficiently elucidated. We conducted a randomized, blinded, crossover intervention study in four representative cities in China in which 128 healthy university students spent 2-h walking along a busy road wearing either a real or a sham respirator and then spent the next 5-h indoors away from traffic pollution. Lung function, blood pressure, and heart rate variability were continuously measured throughout the visit. Linear mixed-effect models were fitted to evaluate the protective effects of respirator intervention on the cardiopulmonary indicators. Results showed that the beneficial effects of respirator intervention were only occasionally significant at specific time points or in specific cities or in selected parameters. Overall, respirator intervention was associated with reduced SBP (6.2 vs. 11.5 mmHg compared to baseline, p < 0.05) and increased LF (44 vs. 35 ms² compared to baseline, p < 0.05) over the 2-h walk, but no significant effects were found over the 7-h period. Respirators have significant effect modifications on the associations between PM_2.5/PM₁₀ and the cardiopulmonary indicators, but the directions of effects were inconsistent. The intercity difference in the effects of respirator intervention was found significant, with Taiyuan and Shanghai to be the two cities with lower personal PM concentrations but more pronounced benefits. In conclusion, reducing personal exposure to PM can have some beneficial effects in some scenarios. However, respirators may not provide sufficient protection from air pollution overall, and we should avoid over-reliance on respirators and accelerate efforts to reduce emissions of pollutants in the first place. Despite standardized procedures, we found inconsistency in results across cities, consistent with the previous literature.

Neuromodulation Applied to Diseases: The Case of HRV Biofeedback

The vagus or “wandering” nerve is the main branch of the parasympathetic nervous system (PNS), innervating most internal organs crucial for health. Activity of the vagus nerve can be non-invasively indexed by heart-rate variability parameters (HRV). Specific HRV parameters predict less all-cause mortality, lower risk of and better prognosis after myocardial infarctions, and better survival in cancer. A non-invasive manner for self-activating the vagus is achieved by performing a slow-paced breathing technique while receiving visual feedback of one’s HRV, called HRV-biofeedback (HRV-B). This article narratively reviews the biological mechanisms underlying the role of vagal activity and vagally mediated HRV in hypertension, diabetes, coronary heart disease (CHD), cancer, pain, and dementia. After searching the literature for HRV-B intervention studies in each condition, we report the effects of HRV-B on clinical outcomes in these health conditions, while evaluating the methodological quality of these studies. Generally, the levels of evidence for the benefits of HRV-B is high in CHD, pain, and hypertension, moderate in cancer, and poor in diabetes and dementia. Limitations and future research directions are discussed.

SUDOSCAN, an Innovative, Simple and Non-Invasive Medical Device for Assessing Sudomotor Function

Diabetic autonomic neuropathy is probably the most undiagnosed but serious complication of diabetes. The main objectives were to assess the prevalence of peripheral and autonomic neuropathy in a population of diabetic patients, analyze it in a real-life outpatient unit scenario and determine the feasibility of performing SUDOSCAN tests together with widely used tests for neuropathy. A total of 33 patients were included in the study. Different scoring systems (the Toronto Clinical Neuropathy Score-TCNS; the Neuropathy Disability Score-NDS; and the Neuropathy Symptom Score-NSS) were applied to record diabetic neuropathy (DN), while the SUDOSCAN medical device was used to assess sudomotor function, detect diabetic autonomic neuropathy and screen for cardiac autonomic neuropathy (CAN). Fifteen (45.5%) patients had sudomotor dysfunction. The SUDOSCAN CAN risk score was positively correlated with the hands' electrochemical sweat conductance (ESC), diastolic blood pressure (DBP), the level of the glycated hemoglobin, as well as with the TCNS, NDS and NSS. Performing SUDOSCAN tests together with other tests for DN proved to be a feasible approach that could be used in daily clinical practice in order to screen for DN, as well as for the early screening of CAN, before more complex and time-consuming tests.

Heart rate variability, perceived stress and willingness to seek counselling in undergraduate students

OBJECTIVE

The primary aim was to determine the level of stress in Czech pharmacy students using both subjective and physiological markers of stress throughout their study. The secondary aim was to investigate association of stress with sociodemographic and clinical characteristics, and to determine the predictors of the likelihood of enrolling in psychotherapy counselling.

METHODS

Design: A prospective observational study.

SETTING

Faculty of Pharmacy in Hradec Kralove, Czech Republic.

SUBJECTS

175 s-year pharmacy students in 2016, 149 students in 2017, and 51 students in 2018.

OUTCOME MEASURES

Perceived stress scale (PSS-10), heart rate variability (HRV, emWavePro), a self-administered survey (sociodemographic and clinical data, likelihood of enrolling in psychotherapy counselling).

RESULTS

The average PSS score was 18.3 ± 6.7. There were no significant changes in PSS-10 and HRV parameters between 2016 and 2018. There was a significant negative correlation between PSS-10 and LF power (p = 0.012). Female gender and poor health status were more frequently observed among the respondents with impaired HRV (p = 0.026 for female gender and p = 0.025 and p = 0.042 for poor health status). Fifty-nine percent of students would be likely to enroll in psychotherapy counselling, with men being significantly less inclined to participate compared to women (p = 0.01).

CONCLUSION

Czech pharmacy students experience moderate levels of stress throughout their studies, which correlates with physiological markers of stress as well as their overall health. Push and pull factors of using mind-body interventions to manage stress should be further examined, especially in high risk groups.

Effects of Resistance Training Intensity on Heart Rate Variability at Rest and in Response to Orthostasis in Middle-Aged and Older Adults

OBJECTIVE

Aging and deficits related to decreased physical activity can lead to higher risks of autonomic nervous system (ANS) dysfunction. The aim of this study was to evaluate the effects of 24 weeks of resistance training (RT) at various intensities on hemodynamics as well as heart rate variability (HRV) at rest and in response to orthostatic tests in middle-aged and older adults.

METHODS

Forty adults were randomized into three groups: high-intensity (HEX) (80% 1-RM) (11 female, 4 male; 60 ± 4 years); low-moderate-intensity (LEX) (50% 1-RM) (nine female, four male; 61 ± 5 years); and a control group (CON) (eight female, four male; 60 ± 4 years). The RT program consisted of nine exercises, with two sets performed of each exercise two times per week for 24 weeks. Data collected included 1-RM, heart rate, and blood pressure and HRV at rest and in response to orthostasis.

RESULTS

Both the HEX (42-94%) and LEX (31.3-51.7%) groups showed increases in 1-RM (p < 0.01). The HEX group showed decreases in resting heart rate (-4.0%), diastolic blood pressure (-3.2 mmHg (-4.2%)), and low frequency/high frequency (LF/HF) (Ln ratio) (p < 0.05). Post-study, the HEX group had higher HF (Ln ms²) than the CON, adjusted for pre-study value and age (p < 0.05). Post-study, the supine-standing ratio (SSR) of LFn (normalized unit) in the HEX group was greater than that in the LEX and CON groups, while the SSR of LF/HF in the HEX group was greater than the CON (p < 0.05). In conclusion, high-intensity RT can improve resting heart rate and HRV by enhancing cardiac vagal control. High-intensity RT might also improve the orthostatic response in terms of HRV. High intensity RT might assist ANS modification and could perhaps decrease the risks of cardiovascular disease and orthostatic intolerance.

Associations between Heart Rate Variability Parameters and Hemodynamic Profiles in Patients with Primary Arterial Hypertension, Including Antihypertensive Treatment Effects

Background: Autonomic nervous system (ANS) dysfunction is an important factor in the development and progression of arterial hypertension (AH) and may produce adverse hemodynamic sequelae. ANS function can be evaluated by analyzing heart rate variability (HRV). The purpose of this study was to assess the possible correlation between HRV and the hemodynamic profile of AH patients, including antihypertensive treatment effects after 12 months. Methods: The study was conducted on 144 patients with uncomplicated AH. The hemodynamic profile was assessed via echocardiography and impedance cardiography (ICG). The analyzed HRV parameters included SDNN, rMSSD, pNN50, low frequency (LF, 0.05–0.15 Hz), high frequency (HF, 0.15–0.4 Hz), total power (TP, the variance of all NN intervals), and the day, night, and 24-h low-to-high frequency ratios (LF/HF). Results: Analysis showed various correlations of HRV parameters both with arterial blood pressure and with the hemodynamic profile assessed via echocardiography and ICG. The HRV parameters of increased ANS activity showed a correlation with improved left ventricle function (LV) and lower LV afterload. Conclusions: Effective antihypertensive treatment demonstrated beneficial effects on both the ANS balance and the hemodynamic profile.

Cardiac Autonomic Modulation and Response to Sub-Maximal Exercise in Chilean Hypertensive Miners

Cardiac autonomic modulation in workers exposed to chronic intermittent hypoxia (CIH) has been poorly studied, especially considering hypertensive ones. Heart rate variability (HRV) has been proven as valuable tool to assess cardiac autonomic modulation under different conditions. The aim of this study is to investigate the cardiac autonomic response related to submaximal exercise (i.e., six-minute walk test, 6MWT) in hypertensive (HT, n = 9) and non-hypertensive (NT, n = 10) workers exposed for > 2 years to CIH. Participants worked on 7-on 7-off days shift between high altitude (HA: > 4.200 m asl) and sea level (SL: < 500 m asl). Data were recorded with electrocardiography (ECG) at morning upon awakening (10 min supine, baseline), then at rest before and after (5 min sitting, pre and post) the 6MWT, performed respectively on the first day of their work shift at HA, and after the second day of SL sojourn. Heart rate was higher at HA in both groups for each measurement (p < 0.01). Parasympathetic indices of HRV were lower in both groups at HA, either in time domain (RMSSD, p < 0.01) and in frequency domain (log HF, p < 0.01), independently from measurement's time. HRV indices in non-linear domain supported the decrease of vagal tone at HA and showed a reduced signal's complexity. ECG derived respiration frequency (EDR) was higher at HA in both groups (p < 0.01) with interaction group x altitude (p = 0.012), i.e., higher EDR in HT with respect to NT. No significant difference was found in 6MWT distance regarding altitude for both groups, whereas HT covered a shorter 6MWT distance compared to NT (p < 0.05), both at HA and SL. Besides, conventional arm-cuff blood pressure and oxygen blood saturation values (recorded before, at the end and after 5-min recovery from 6MWT), reported differences related to HA only. HA is the main factor affecting cardiac autonomic modulation, independently from hypertension. However, presence of hypertension was associated with a reduced physical performance independently from altitude, and with higher respiratory frequency at HA.

Ten-Second Heart Rate Variability, Its Changes Over Time, and the Development of Hypertension

BACKGROUND

The role of ultrashort-term heart rate variability (HRV) and its temporal changes in incident hypertension are unknown. We aimed to investigate the association between 10-second HRV, its changes, and incident hypertension in adults aged <40 years and older.

METHODS

This cohort study included 232 587 Koreans (mean age 37.6 years) without hypertension. Hypertension was defined according to the 2017 American College of Cardiology and American Heart Association hypertension guidelines. HRV, including the root mean square of successive RR interval differences and the SD of normal-to-normal RR intervals, was estimated using standard 12-lead, 10-second electrocardiography.

RESULTS

During a median follow-up of 3.8 years, 40 268 hypertension cases were identified (incidence rates: 36.1 and 67.9 per 1000 person-years for young and older participants, respectively). An inverse association was observed between HRV and hypertension risk, in a dose-dependent manner. The multivariable-adjusted hazard ratios (95% CIs) for hypertension comparing the first to the fifth quintiles of root mean square of successive RR interval difference and SD of normal-to-normal RR interval were 1.58 (1.52-1.63) and 1.35 (1.30-1.39), respectively. These associations were stronger in young adults than in older adults. In a subsample of 150 301 participants, compared with stable HRV, an increase in HRV over time was also inversely associated with incident hypertension.

CONCLUSIONS

A higher HRV and its increase over time on a 10-second electrocardiography were associated with a lower risk of hypertension. Our findings indicate that autonomic function, estimated using 10-second standard electrocardiography, plays a role in predicting hypertension, with a stronger effect in young adults.

Heart rate variability and cognitive performance in adults with cardiovascular risk

BACKGROUND

Heart rate variability (HRV), a measure of autonomic function, has been associated with both cardiovascular disease and cognitive dysfunction. In turn, cardiovascular risk has been linked to an increased risk of dementia onset. However, whether autonomic dysfunction may represent an early marker of cognitive decline in individuals with high cardiovascular risk is still an open issue.

METHODS

We performed a complete 24-hour HRV analysis in 50 middle-aged and elderly subjects with cardiovascular risk as assessed with the European Society of Cardiology Systematic Coronary Risk Evaluation (ESC SCORE). Cognitive performance was evaluated by Montreal Cognitive Assessment (MoCA), Free and Cued Selective Reminding Test (FCSRT) and Stroop Color and Word Test. Stepwise regression was used to identify significant associations between 24-hour ambulatory ECGs parameters and cognitive performances.

RESULTS

There were 30 women and 20 men with mean age of 64.9 years (range 51-77) and the mean ESC SCORE was 6%. Four subjects were diagnosed with mild cognitive impairment. Associations were found between measures of HRV and measures of cognition. Ultra-low frequency (ULF) band power of HRV significantly correlated with MoCA (r = 0.424, p = 0.003), also after adjustment for demographics and education. A significant association was also found between the ESC SCORE and ULF band power (r = -0.470, p = 0.0009).

CONCLUSIONS

Ultra-low frequency band power of HRV is associated with cognitive performance of middle-aged and elderly subjects with cardiovascular risk. This finding may indicate that autonomic nervous system dysregulation plays a role in developing cardiovascular risk and cognitive decline.

Feasibility of using ecological momentary assessment and continuous heart rate monitoring to measure stress reactivity in natural settings

The way people respond to stressful situations (i.e., stress reactivity) varies widely. Researchers typically measure stress reactivity in controlled studies, but this is limited because laboratory stressors cannot capture the variety, severity, or duration of stressors that individuals face in their daily lives. The present study examined the feasibility of using ecological momentary assessment (EMA) and a wireless electrocardiography (ECG) patch to develop an understanding of stress reactivity in natural settings. Thirty-five adult women completed EMA surveys about stressors they were exposed to while wearing a wireless ECG monitor for 7 consecutive days. Daily stressors were measured using seven questions adapted from the Daily Inventory of Stressful Events and a stressor interval was defined as the presence of at least one stressor during the EMA survey prompt. Participants wore the Cardea SOLO wireless ECG monitor (Cardiac Insight Inc., Bellevue, WA) to continuously track their heart rate. Participant-specific differences in 5-minute heart rate variability (HRV) between intervals when participants did and did not report stressors were calculated and displayed in a heat map. Survey response rate was satisfactory (72.0%, n = 588) and nearly all participants (33 out of 35) reported both stressor and non-stressor intervals. Each participant reported at least one stressor on approximately 35% of completed surveys while wearing the ECG patch. Mean wear time (6.6 days) and the duration of analyzable data with an ECG monitor were close to the 7-day study period. While many participants had lower HRV during stressor versus non-stressor intervals, the magnitude and direction of these differences varied widely. In summary, we found that a 7-day sampling scheme combining ecological momentary assessment (EMA) with HRV measured using continuous ECG monitoring was feasible and effective in capturing a variety of daily stressors and measuring autonomic stress reactivity.

Autonomic Measures in Differentiating Depressive Disorders: A Potential AID

Objective

The present study aimed at exploring the potential utility of autonomic regulation as a useful marker in the diagnostic differentiation between unipolar and bipolar depression.

Method

Respiratory sinus arrhythmia (RSA), low-frequency (LF) of heart rate variability, and systolic blood pressure (SBP) were assessed in patients with bipolar depression (31) and major depressive disorder (MDD=32), and in healthy controls (HCs=32). Since bipolar depressed subjects were maintained on specific medications to manage manic/hypomanic symptoms, we explored whether mood stabilizers (atypical antipsychotics and anticonvulsants or their combinations) could independently affect the physiological parameters.

Results

When the autonomic measures were analyzed by a multivariate analysis of variance (MANCOVA), after controlling for BMI, the combination of variables (RSA, LF, SBP) discriminated patients with bipolar depression and MDD from HC (F₍6_{, 178)}=3.036, p=0.007, Λ=0.823, partial η²=0.093). In any case, we cannot exclude that mood stabilizers might have affected SBP values in the bipolar group. To deconstruct this multivariate effect, pairwise ANOVAs and discriminant analyses contrasted groups and documented that RSA was the primary variable distinguishing the groups. Discriminant function analyses showed that RSA had a significant discriminating weight between bipolar depressed patients and HC subjects (p<0.0005). By contrast, RSA showed a trend towards the statistical significance in discriminating between bipolar depression and MDD patients (p=0.06).

Conclusions

The assessment of RSA and SBP in outpatient settings might be helpful in the differential diagnosis of affective disorders.

Obstructive Sleep apnea and cardiovascular events in Elderly Patients

INTRODUCTION

In recent decades, life expectancy has increased considerably. The cardiovascular effects of Obstructive Sleep Apnea (OSA) in the elderly lead to patient disability and high resource consumption. Intermittent nocturnal hypoxia leads to hemodynamic stress and adrenergic activation, which promotes cardiovascular disease. However, chronic intermittent hypoxia may protect elderly patients from cardiovascular events (CVE) due to biological adaptation.

AREAS COVERED

OSA patients are at increased risk of cardiovascular events. The severity of OSA increases cardiovascular risk, and this association also exists in the elderly. This article reviews the association between OSA, CPAP treatment, and CVE, particularly stroke and coronary heart disease (CHD), in the elderly. MEDLINE and the Cochrane Collaboration databases were searched from inception to July 2021.

EXPERT COMMENTARY

Although a positive association between OSA and the incidence of cardiovascular disease in the elderly has been established, the role of sleep apnea in certain cardiovascular events remains controversial. Most authors agree that untreated OSA is a risk factor for stroke or worse stroke prognosis. However, the association between OSA and CHD is usually less pronounced than between OSA and stroke, especially in the elderly.