Autonomic Profile Research Articles

Bio-optical variability of particulate matter in the Southern Ocean

The composition and size distribution of particles in the ocean control their optical (scattering and absorption) properties, as well as a range of biogeochemical and ecological processes. Therefore, they provide important information about the pelagic ocean ecosystem’s structure and functioning, which can be used to assess primary production, particle sinking, and carbon sequestration. Due to its harsh environment and remoteness, the particulate bio-optical properties of the Southern Ocean (SO) remain poorly observed and understood. Here, we combined field measurements from hydrographic casts from two research voyages and from autonomous profiling floats (BGC-Argo) to examine particulate bio-optical properties and relationships among several ecologically and optically important variables, namely the phytoplankton chlorophyll a concentration (Chl), the particulate absorption coefficient (ap), the particulate backscattering coefficient (bbp), and the particulate organic carbon (POC) concentration. In the clearest waters of the SO (Chl < 0.2 mg m−3), we found a significant contribution to absorption by non-algal particles (NAP) at 442 nm, which was up to 10 times greater than the absorption by phytoplankton. This makes the particulate bio-optical properties there remarkably different from typical oceanic case 1 water. A matchup analysis confirms the impact of this larger NAP absorption on the retrieval of Chl from satellite ocean colour observations. For waters with Chl > 0.2 mg m−3, no significant differences are observed between the SO and temperate waters. Our findings also demonstrate consistency in predicting phytoplankton carbon from either Chl or bbp, suggesting that both methods are applicable in the SO.

Postpartum Blood Pressure Variability and Heart Rate Variability in Preeclampsia.

Preeclampsia is associated with autonomic dysregulation during pregnancy; however, less is known about autonomic function in the first week postpartum after preeclampsia. We retrospectively analyzed data from a prospective cohort of women with and without preeclampsia. Continuous blood pressure and heart rate were measured with finger plethysmography within 7 days postpartum. Frequency-domain blood pressure and heart rate variability (HRV) were calculated using spectral analysis. Time-domain HRV was calculated as the root mean square of successive RR interval differences. We compared results between those with and without preeclampsia, as well as between those with new-onset preeclampsia, chronic hypertension with superimposed preeclampsia, and normotensive participants. A total of 70 postpartum women were enrolled: 20 normotensive, 29 new-onset preeclampsia, and 21 superimposed preeclampsia. Both low- and high-frequency blood pressure variabilities were higher in those with preeclampsia compared with controls (P=0.04 and P=0.02, respectively). This difference was driven by those with new-onset preeclampsia. The preeclampsia group had lower high-frequency HRV (P<0.005), a higher low-/high-frequency ratio of HRV (P<0.005), and lower time-domain HRV (P=0.01); this difference was seen in those with and without chronic hypertension. Postpartum patients with preeclampsia with and without chronic hypertension had lower HRV compared with normotensive postpartum controls. Higher blood pressure variability was observed only in those with nonsuperimposed preeclampsia, suggesting that the autonomic profile of preeclampsia may differ in patients with chronic hypertension.

Effects of an 8-week intervention of anulom vilom pranayama combined with heartfulness meditation on psychological stress, autonomic function, inflammatory biomarkers, and oxidative stress in healthcare workers during COVID-19 pandemic: a randomized controlled trial.

Health care workers were exposed to huge stress during COVID-19 pandemic affecting their physical and mental health. Practice of anulom vilom pranayama andheartfulness meditation (AVPHFN) can improve mental and physical health and counter stress. The present study explored the effect of 8-week AVPHFN intervention on autonomic functions, emotional stress, oxidative stress, andinflammation markers in the nurse group of health-care givers. This was a randomized controlled trial where 50 nurses underwent AVPHFN and 50 participated as controls. At baseline and after 8week intervention of AVPHFN anthropometric parameters, cardiovascular parameters, autonomic function including time and frequency domain parameters, biochemical parameters, and psychological stress using the questionnaire were assessed. Forty nurses in AVPHFN group and 46 in control group completed the study. AVPHFN intervention resulted ina significant reduction in cardiovascular parameters heart rate, systolic blood pressure, diastolic blood pressure, mean arterial pressure and rate pressure product (p<0.001,p<0.001, p<0.001, p<0.001, and p<0.001, respectively), perceived stress score and depression, anxiety, andstress scale psychological variables of depression, andstress compared to the control group. Total power, ratioof low frequency to high frequency and change in successive normal sinus (NN) intervals exceeds 50 ms (p<0.01, p=0.05, and p<0.01 respectively) suggesting parasympathodominance due to higher vagal efferent activity. Serum cortisol, high-sensitivity C-reactive protein (hs-CRP), tumor necrosis factor-alpha, interleukin (IL)-1, IL-6 and telomerase significantly decreased in AVPHFN group post intervention. Eighty-week intervention of AVPHFN improved psychophysiological, autonomic and biochemistry profile of nurse group of health-care workers. AVPHFN module may be beneficial for curtailing stress and improving well-being.

Sleep and cardiac autonomic modulation in older adults: Insights from an at-home study with auditory deep sleep stimulation.

The autonomic nervous system regulates cardiovascular activity during sleep, likely impacting cardiovascular health. Aging, a primary cardiovascular risk factor, is associated with cardiac autonomic disbalance and diminished sleep slow waves. Therefore, slow waves may be linked to aging, autonomic activity and cardiovascular health. However, it is unclear how sleep and slow waves are linked to cardiac autonomic profiles across multiple nights in older adults. We conducted a randomized, crossover trial involving healthy adults aged 62-78 years. Across 2 weeks, we applied auditory stimulation to enhance slow waves and compared it with a SHAM period. We measured sleep parameters using polysomnography and derived heart rate, heart rate variability approximating parasympathetic activity, and blood pulse wave approximating sympathetic activity from a wearable. Here, we report the results of 14 out of 33 enrolled participants, and show that heart rate, heart rate variability and blood pulse wave within sleep stages differ between the first and second half of sleep. Furthermore, baseline slow-wave activity was related to cardiac autonomic activity profiles during sleep. Moreover, we found auditory stimulation to reduce heart rate variability, while heart rate and blood pulse wave remained unchanged. Lastly, within subjects, higher heart rate coincided with increased slow-wave activity, indicating enhanced autonomic activation when slow waves are pronounced. Our study shows the potential of cardiac autonomic markers to offer insights into participants' baseline slow-wave activity when recorded over multiple nights. Furthermore, we highlight that averaging cardiac autonomic parameters across a night may potentially mask dynamic effects of auditory stimulation, potentially playing a role in maintaining a healthy cardiovascular system.

Microeukaryote metabolism across the western North Atlantic Ocean revealed through autonomous underwater profiling

Microeukaryotes are key contributors to marine carbon cycling. Their physiology, ecology, and interactions with the chemical environment are poorly understood in offshore ecosystems, and especially in the deep ocean. Using the Autonomous Underwater Vehicle Clio, microbial communities along a 1050 km transect in the western North Atlantic Ocean were surveyed at 10–200 m vertical depth increments to capture metabolic signatures spanning oligotrophic, continental margin, and productive coastal ecosystems. Microeukaryotes were examined using a paired metatranscriptomic and metaproteomic approach. Here we show a diverse surface assemblage consisting of stramenopiles, dinoflagellates and ciliates represented in both the transcript and protein fractions, with foraminifera, radiolaria, picozoa, and discoba proteins enriched at >200 m, and fungal proteins emerging in waters >3000 m. In the broad microeukaryote community, nitrogen stress biomarkers were found at coastal sites, with phosphorus stress biomarkers offshore. This multi-omics dataset broadens our understanding of how microeukaryotic taxa and their functional processes are structured along environmental gradients of temperature, light, and nutrients.

A float-based Ocean color vicarious calibration program

Ocean color satellites require a procedure known as System Vicarious Calibration (SVC) after launch as the pre-launch and on-orbit calibration accuracy is insufficient. The current approach for determination of post-launch SVC uses a single fixed measurement location and may be susceptible to unexpected biases in satellite processing algorithms. Here we describe a novel SVC program which is based on a high resolution and high accuracy radiometric system integrated with an autonomous profiling float (providing a buoyancy engine, physical observations, and communication). This float + radiometer (HyperNav) system can be shipped via air, land, ocean and is deployable from small boats. This SVC program relies on multiple deployment sites with associated facilities to collect a significant amount of SVC quality data in a relatively short time. It has centralized logistics and command-and-control centers ensuring easy access to information regarding the status of each asset and to ensure floats stay within a certain ocean area. The development of the program has been associated with the launch of NASA’s PACE satellite and has been executed by academic institutions in collaboration with an industrial partner. Other approaches for a future float-based operational SVC program are discussed.

Using Precision Medicine to Disentangle Genotype-Phenotype Relationships in Twins with Rett Syndrome: A Case Report.

Rett syndrome (RTT) is a paediatric neurodevelopmental disorder spanning four developmental stages. This multi-system disorder offers a unique window to explore genotype-phenotype relationships in a disease model. However, genetic prognosticators of RTT have limited clinical value due to the disorder's heterogeneity on multiple levels. This case report used a precision medicine approach to better understand the clinical phenotype of RTT twins with an identical pathogenic MECP2 mutation and discordant neurodevelopmental profiles. Targeted genotyping, objective physiological monitoring of heart rate variability (HRV) parameters, and clinical severity were assessed in a RTT twin pair (5 years 7 months old) with an identical pathogenic MECP2 mutation. Longitudinal assessment of autonomic HRV parameters was conducted using the Empatica E4 wristband device, and clinical severity was assessed using the RTT-anchored Clinical Global Impression Scale (RTT-CGI) and the Multi-System Profile of Symptoms Scale (MPSS). Genotype data revealed impaired BDNF function for twin A when compared to twin B. Twin A also had poorer autonomic health than twin B, as indicated by lower autonomic metrics (autonomic inflexibility). Hospitalisation, RTT-CGI-S, and MPSS subscale scores were used as measures of clinical severity, and these were worse in twin A. Treatment using buspirone shifted twin A from an inflexible to a flexible autonomic profile. This was mirrored in the MPSS scores, which showed a reduction in autonomic and cardiac symptoms following buspirone treatment. Our findings showed that a combination of a co-occurring rs6265 BDNF polymorphism, and worse autonomic and clinical profiles led to a poorer prognosis for twin A compared to twin B. Buspirone was able to shift a rigid autonomic profile to a more flexible one for twin A and thereby prevent cardiac and autonomic symptoms from worsening. The clinical profile for twin A represents a departure from the disorder trajectory typically observed in RTT and underscores the importance of wider genotype profiling and longitudinal objective physiological monitoring alongside measures of clinical symptoms and severity when assessing genotype-phenotype relationships in RTT patients with identical pathogenic mutations. A precision medicine approach that assesses genetic and physiological risk factors can be extended to other neurodevelopmental disorders to monitor risk when genotype-phenotype relationships are not so obvious.

Autonomic and Enteric Profiling May Help Predict Response to Diverse Obesity Therapies.

Changes in autonomic (ANS) and enteric nervous systems (ENS) may be involved in pathogenesis of obesity. We hypothesized that baseline autonomic and enteric parameters may predict outcomes of diverse obesity therapies. We studied ANS and ENS physiology in 37 patients (8 male, 29 female, age 45years, weight 129.7kg) at 4 centers in patients undergoing medical (9: low-calorie diet) versus invasive (22: 16 sleeve, 6 bypass) and semi-invasive (6: 2 band, 2 high energy stimulation, 2 aspiration) weight loss therapies. Weight loss was reported as percent weight loss from baseline to latest values at 1year and in some up to 5years; classified as < or > /= 20% for each group. ANS testing included sympathetic adrenergic function by measuring reflex vasoconstriction and postural adjustment ratio. ENS was measured non-invasively using cutaneous low-resolution electrogastrogram. Percent weight loss was greater with the invasive (28.5%) than semi-invasive (9.1%) or non-invasive low-calorie diet (4.4%) (p < .001). Percent weight loss at 1year (and up to 5years) corresponded to the adrenergic measure of postural adjustment ratio (r = .42, p = .012), total pulse amplitude at rest (r = .56, p < .001), and electrogastrogram standing-to-rest difference (r = .33, p = .056). Baseline autonomic and enteric function measures correspond to percentage with loss in this pilot study using diverse weight loss methods. Autonomic and enteric profiling has potential clinical use for evaluation and treatment of obesity but needed larger controlled trials.

A - 42 Differences in Exercise Tolerance and Autonomic Function Based on Concussion Clinical Profile

Abstract Purpose This study examined differences in clinical profiles (e.g., post-traumatic migraine, vestibular, anxiety/mood, oculomotor, and cognitive) between exercise tolerance groups determined by the Buffalo Concussion Bike Test (BCBT). We hypothesized the exercise-intolerant group would be more likely to have anxiety and/or vestibular profiles. Method Patients (18–49 years; 8 days to 6 months from concussion) completed demographic and medical history, the Clinical Profile Screen, Brief Symptom Inventory-18, and BCBT. Participants were adjudicated into one or more clinical profiles and classified as exercise tolerant or intolerant. Independent-sample t-tests and chi-square tests were used to compare demographics, clinical profiles, reasons for stopping the BCBT, and ANS metrics. Results One hundred six participants (mean age = 27.9¬ ± 8.1, 62.3% female) were included in the study (71 exercise-intolerant; 35 exercise-tolerant). No demographic or medical history differences were noted between groups. The exercise-intolerant group had significantly lower odds of having an adjudicated headache profile (OR = 0.39, 95%CI = 0.16–0.93, p = 0.03) and significantly greater odds of having an adjudicated autonomic profile (OR = 2.28, 95%CI = 1.01–5.21, p = 0.04). A greater proportion of those with the vestibular profile stopped the BCBT due to symptom exacerbation than those without (90.5% vs. 9.5%, p = 0.04). Conclusions Adjudicated clinical profiles and ANS metrics were similar between exercise-tolerant and intolerant groups. Vestibular sensitivities have a considerable contribution to symptom provocation during the BCBT, as a significant proportion of participants with the vestibular profile discontinued the BCBT due to symptom exacerbation. These findings corroborate previous research and suggest that exercise intolerance is pervasive across all concussion clinical profiles and should be considered in all evaluations.

Impact of optimized transcutaneous auricular vagus nerve stimulation on cardiac autonomic profile in healthy subjects and heart failure patients

Objective. To determine the optimal frequency and site of stimulation for transcutaneous vagus nerve stimulation (tVNS) to induce acute changes in the autonomic profile (heart rate (HR), heart rate variability (HRV)) in healthy subjects (HS) and patients with heart failure (HF). Approach. We designed three single-blind, randomized, cross-over studies: (1) to compare the acute effect of left tVNS at 25 Hz and 10 Hz (n = 29, age 60 ± 7 years), (2) to compare the acute effect of left and right tVNS at the best frequency identified in study 1 (n = 28 age 61 ± 7 years), and (3) to compare the acute effect of the identified optimal stimulation protocol with sham stimulation in HS and HF patients (n = 30, age 59 ± 5 years, and n = 32, age 63 ± 7 years, respectively). Main results. In study 1, left tragus stimulation at 25 Hz was more effective than stimulation at 10 Hz in decreasing HR (−1.0 ± 1.2 bpm, p < 0.001 and −0.5 ± 1.6 bpm, respectively) and inducing vagal effects (significant increase in RMSSD, and HF power). In study 2, the HR reduction was greater with left than right tragus stimulation (−0.9 ± 1.5 bpm, p < 0.01 and −0.3 ± 1.4 bpm, respectively). In study 3 in HS, left tVNS at 25 Hz significantly reduced HR, whereas sham stimulation did not (−1.1 ± 1.2 bpm, p< 0.01 and −0.2 ± 2.9 bpm, respectively). In HF patients, both active and sham stimulation produced negligible effects. Significance. Left tVNS at 25 Hz is effective in acute modulation of cardiovascular autonomic control (HR, HRV) in HS but not in HF patients (NCT05789147).

A Study on the Observation Status and Monitoring of Large Ocean Observation Buoys

More than half of the world's population is lives in coastal areas, and the effects of climate change are increasing. In particular, the prediction, forecasting, prevention and mitigation of disasters in coastal regions underscore the importance of real-time environmental information. This paper addresses the deployment and status of Large Ocean Observation Buoys installed by KIOST in the Yellow Sea/East China Sea in 2021. The buoys provide real-time time-series information not only for ocean physical and meteorological variables, but also for biogeochemical variables. In addition, the installed smart autonomous profiling system enables remote acquisition of vertical profiles of seawater. The data collected by the buoys will be visualized and displayed in real time on a web page. This study demonstrates the role of the buoys in monitoring ocean disasters and hazards using data collected during Typhoon Hinnamnor in 2022 and the low salinity water expansion of the Yangtze River. The use of the buoys for ocean monitoring is expected to be an effective means of responding to dynamic and abrupt environmental changes in the field, thus supporting rapid and effective responses to ocean disasters and hazards.

Design and verification of a highly accurate in-situ hyperspectral radiometric measurement system (HyperNav)

Hyperspectral optical observations of the Earth’s surface oceans from space offer a means to improve our understanding of ocean biology and biogeochemistry. NASA’s Plankton, Aerosol, Cloud, ocean Ecosystem (PACE) satellite mission, which includes a hyperspectral ocean color instrument (OCI), will provide radiometric observations of surface ocean with near continuous spectral resolution across the near UV to NIR range. Maintaining sufficient accuracy over the lifetime of satellite ocean color missions requires a robust program for system vicarious calibration (SVC) and product validation. The system vicarious calibration process combines satellite sensor data with in-situ radiometric/optical measurements to remove potential biases due to the combined errors from both satellite radiometric sensor calibration and atmospheric correction. As such, high accuracy, high-spectral resolution in-situ radiometric measurements are required to provide a principal source of truth for the satellite-derived products. To meet the requirements, a novel in-situ radiometric system, called HyperNav, has been developed, rigorously characterized and field tested. Key attributes of HyperNav are dual upwelling radiance heads coupled to individual spectrometers, spectral resolution of ∼2.2 nm (full width, half-maximum) across 320–900 nm, integrated shutter systems for dark measurements, and integrated tilt and pressure sensors. The HyperNav operational modes include traditional profiling and surface modes, as well as integration with an autonomous profiling float for unattended deployment, offering a new capability for a network of autonomous platforms to support the long-term needs for hyperspectral ocean color remote sensing observations. This paper describes the HyperNav design, in-situ operational modes, and field verification results.

Autonomic profiling in primary autonomic failure: Insights from 30 cases

Autonomic profiling in primary autonomic failure: Insights from 30 cases

One-third of Southern Ocean productivity is supported by dust deposition.

Natural iron fertilization of the Southern Ocean by windblown dust has been suggested to enhance biological productivity and modulate the climate1-3. Yet, this process has never been quantified across the Southern Ocean and at annual timescales4,5. Here we combined 11 years of nitrate observations from autonomous biogeochemical ocean profiling floats with a Southern Hemisphere dust simulation to empirically derive the relationship between dust-iron deposition and annual net community production (ANCP) in the iron-limited Southern Ocean. Using this relationship, we determined the biological response to dust-iron in the pelagic perennially ice-free Southern Ocean at present and during the last glacial maximum (LGM). We estimate that dust-iron now supports 33% ± 15% of Southern Ocean ANCP. During the LGM, when dust deposition was 5-40-fold higher than today, the contribution of dust to Southern Ocean ANCP was much greater, estimated at 64% ± 13%. We provide quantitative evidence of basin-wide dust-iron fertilization of the Southern Ocean and the potential magnitude of its impact on glacial-interglacial timescales, supporting the idea of the important role of dust in the global carbon cycle and climate6-8.

Different heart rate variability profile during sleep in mid-later life adults with remitted early-onset versus late-onset depression

BackgroundIn mid-later life adults, early-onset and late-onset (i.e., onset ≥50 years) depression appear to be underpinned by different pathophysiology yet have not been examined in relation to autonomic function. Sleep provides an opportunity to examine the autonomic nervous system as the physiology changes across the night. Hence, we aimed to explore if autonomic profile is altered in mid-later life adults with remitted early-onset, late-onset and no history of lifetime depression. MethodsParticipants aged 50–90 years (n = 188) from a specialised clinic underwent a comprehensive clinical assessment and completed an overnight polysomnography study. General Linear Models were used to examine the heart rate variability differences among the three groups for four distinct sleep stages and the wake after sleep onset. All analyses controlled for potential confounders – age, sex, current depressive symptoms and antidepressant usage. ResultsFor the wake after sleep onset, mid-later life adults with remitted early-onset depression had reduced standard deviation of Normal to Normal intervals (SDNN; p = .014, d = −0.64) and Shannon Entropy (p = .004, d = −0.46,) than those with no history of lifetime depression. Further, the late-onset group showed a reduction in high-frequency heart rate variability (HFn.u.) during non-rapid eye movement sleep stage 2 (N2; p = .005, d = −0.53) and non-rapid eye movement sleep stage 3 (N3; p = .009, d = −0.55) when compared to those with no lifetime history. LimitationsCausality between heart rate variability and depression cannot be derived in this cross-sectional study. Longitudinal studies are needed to examine the effects remitted depressive episodes on autonomic function. ConclusionThe findings suggest differential autonomic profile for remitted early-onset and late-onset mid-later life adults during sleep stages and wake periods. The differences could potentially serve as peripheral biomarkers in conjunction with more disease-specific markers of depression to improve diagnosis and prognosis.

Neurophysiological and Autonomic Correlates of Metacognitive Control of and Resistance to Distractors in Ecological Setting: A Pilot Study.

In organisational contexts, professionals are required to decide dynamically and prioritise unexpected external inputs deriving from multiple sources. In the present study, we applied a multimethodological neuroscientific approach to investigate the ability to resist and control ecological distractors during decision-making and to explore whether a specific behavioural, neurophysiological (i.e., delta, theta, alpha and beta EEG band), or autonomic (i.e., heart rate-HR, and skin conductance response-SCR) pattern is correlated with specific personality profiles, collected with the 10-item Big Five Inventory. Twenty-four participants performed a novel Resistance to Ecological Distractors (RED) task aimed at exploring the ability to resist and control distractors and the level of coherence and awareness of behaviour (metacognition ability), while neurophysiological and autonomic measures were collected. The behavioural results highlighted that effectiveness in performance did not require self-control and metacognition behaviour and that being proficient in metacognition can have an impact on performance. Moreover, it was shown that the ability to resist ecological distractors is related to a specific autonomic profile (HR and SCR decrease) and that the neurophysiological and autonomic activations during task execution correlate with specific personality profiles. The agreeableness profile was negatively correlated with the EEG theta band and positively with the EEG beta band, the conscientiousness profile was negatively correlated with the EEG alpha band, and the extroversion profile was positively correlated with the EEG beta band. Taken together, these findings describe and disentangle the hidden relationship that lies beneath individuals' decision to inhibit or activate intentionally a specific behaviour, such as responding, or not, to an external stimulus, in ecological conditions.

The Degree of Cardiovascular Autonomic Dysfunction is not Different in GBA-Related and Idiopathic Parkinson's Disease Patients: A Case-Control Instrumental Evaluation.

Increased prevalence of cardiovascular autonomic failure might play a key role on Parkinson's disease (PD) progression of glucocerebrosidase gene (GBA)-mutated patients, determining a malignant phenotype of disease in these patients. To objectively characterize, for the first time, the cardiovascular autonomic profile of GBA-mutated patients compared to idiopathic PD patients by means of cardiovascular reflex tests (CRTs). This is a case-control (1 : 2) study on PD patients belonging to well-characterized prospective cohorts. For each PD patient carrying GBA variants, two idiopathic PD patients, matched for sex and disease duration at CRTs, were selected. Patients recruited in these cohorts underwent a complete clinical and instrumental evaluation including specific autonomic questionnaires, CRTs and extensive genetic analysis. A total of 23 GBA-PD patients (19 males, disease duration 7.7 years) were included and matched with 46 non-mutated PD controls. GBA-mutated patients were younger than controls (59.9±8.1 vs. 64.3±7.2 years, p = 0.0257) and showed a more severe phenotype. Despite GBA-mutated patients reported more frequently symptoms suggestive of orthostatic hypotension (OH) than non-mutated patients (39.1% vs 6.5%, p = 0.001), the degree of cardiovascular autonomic dysfunction, when instrumentally assessed, did not differ between the two groups, showing the same prevalence of neurogenic OH, delayed OH and cardiovascular reflex impairment (pathological Valsalva maneuver). GBA-PD patients did not show different instrumental cardiovascular autonomic pattern than non-mutated PD. Our findings suggested that symptoms suggestive of OH should be promptly investigated by clinicians to confirm their nature and improve patient care and management.

Symptoms Associated With Exercise Intolerance and Resting Heart Rate Following Mild Traumatic Brain Injury.

People may experience a myriad of symptoms after mild traumatic brain injury (mTBI), but the relationship between symptoms and objective assessments is poorly characterized. This study sought to investigate the association between symptoms, resting heart rate (HR), and exercise tolerance in individuals following mTBI, with a secondary aim to examine the relationship between symptom-based clinical profiles and recovery. Prospective observational study of adults aged 18 to 65 years who had sustained mTBI within the previous 7 days. Symptoms were assessed using the Post-Concussion Symptom Scale, HR was measured at rest, and exercise tolerance was assessed using the Buffalo Concussion Bike Test. Symptom burden and symptom-based clinical profiles were examined with respect to exercise tolerance and resting HR. Data from 32 participants were assessed (mean age 36.5 ± 12.6 years, 41% female, 5.7 ± 1.1 days since injury). Symptom burden (number of symptoms and symptom severity) was significantly associated with exercise intolerance ( P = .002 and P = .025, respectively). Physiological and vestibular-ocular clinical profile composite groups were associated with exercise tolerance ( P = .001 and P = .014, respectively), with individuals who were exercise intolerant having a higher mean number of symptoms in each profile than those who were exercise tolerant. Mood-related and autonomic clinical profiles were associated with a higher resting HR (>80 bpm) ( P = .048 and P = .028, respectively), suggesting altered autonomic response for participants with symptoms relating to this profile. After adjusting for age and mechanism of injury (sports- or non-sports-related), having a higher mood-related clinical profile was associated with persisting symptoms at 3 months postinjury (adjusted odds ratio = 2.08; 95% CI, 1.11-3.90; P = .013). Symptom-based clinical profiles, in conjunction with objective measures such as resting HR and exercise tolerance, are important components of clinical care for those having sustained mTBI. These results provide preliminary support for the concept that specific symptoms are indicative of autonomic dysfunction following mTBI.

Heart Rate Variability Measurement Can Be a Point-of-Care Sensing Tool for Screening Postpartum Depression: Differentiation from Adjustment Disorder.

Postpartum depression (PPD) is a serious mental health issue among women after childbirth, and screening systems that incorporate questionnaires have been utilized to screen for PPD. These questionnaires are sensitive but less specific, and the additional use of objective measures could be helpful. The present study aimed to verify the usefulness of a measure of autonomic function, heart rate variability (HRV), which has been reported to be dysregulated in people with depression. Among 935 women who had experienced childbirth and completed the Edinburgh Postnatal Depression Scale (EPDS), HRV was measured in EPDS-positive women (n = 45) 1 to 4 weeks after childbirth using a wearable device. The measurement was based on a three-behavioral-state paradigm with a 5 min duration, consisting of rest (Rest), task load (Task), and rest-after-task (After) states, and the low-frequency power (LF), the high-frequency power (HF), and their ratio (LF/HF) were calculated. Among the women included in this study, 12 were diagnosed with PPD and 33 were diagnosed with adjustment disorder (AJD). Women with PPD showed a lack of adequate HRV regulation in response to the task load, accompanying a high LF/HF score in the Rest state. On the other hand, women with AJD exhibited high HF and reduced LF/HF during the After state. A linear discriminant analysis using HRV indices and heart rate (HR) revealed that both the differentiation of PPD and AJD patients from the controls and that of PPD patients from AJD patients were possible. The sensitivity and specificity for PPD vs. AJD were 75.0% and 90.9%, respectively. Using this paradigm, an HRV measurement revealed the characteristic autonomic profiles of PPD and AJD, suggesting that it may serve as a point-of-care sensing tool in PPD screening systems.

Cardiac autonomic profile, perceived stress and environmental comfort in healthy employees during remote and in-office work

Remote work (REMOTE) causes an overlap between working and domestic demands. The study of the cardiac autonomic profile (CAP) by means of heart rate variability (HRV) provides information about the impact of REMOTE on workers’ health. The primary aim was to determine whether CAP, self-perceived stress, environmental and workstation comfort are modified during REMOTE. The secondary aim was to explore how these indices are influenced by individual and environmental work-related factors. Fifty healthy office employees alternating REMOTE and in-office (OFFICE) working were enrolled, rated self-perceived stress, environmental and workstation comfort using a visual analogue scale and performed a 24-h electrocardiogram during REMOTE and OFFICE. Stress was lower (5.6 ± 2.2 vs. 6.4 ± 1.8), environmental comfort higher (7.7 ± 1.9 vs. 7.0 ± 1.5), and the workstation comfort poorer (6.2 ± 1.8 vs. 7.5 ± 1.2) during REMOTE. CAP was similar during REMOTE and OFFICE. CAP was influenced by some work-related factors, including the presence of offspring, absence of a dedicated workspace during REMOTE and number of working hours. All these variables determined a decreased vagal modulation. The working setting seems to impact the levels of perceived stress and comfort, but not the CAP. However, individual and environmental work-related factors reduce cardiac vagal modulation during REMOTE, potentially increasing the risk of developing cardiovascular diseases.