Smartwatches and home-based blood pressure (BP) devices have permitted easy use of heart rate variability (HRV) and BP to identify the recovery status of users after acute exercise training. The reproducibility of HRV and BP after exercise in healthy young participants is not well known. Eighteen participants (age 27 ± 6 years, female n = 8) performed test and retest aerobic exercises (cycling, 30 min, 60% of peak workload, W) and a control session in randomized order. RMSSD, high and low-frequency power of RR intervals, and BP were measured at rest and 30-60 min after interventions. The relative reproducibility was assessed by the intraclass correlation coefficient (ICC) and 95% confidence interval (95% CI). The absolute reproducibility was evaluated using the coefficient of variation (CV%). HRV indices revealed moderate-to-excellent reproducibility at rest (ICC 0.81-0.86; 95% CI 0.53-0.95) but not after exercise (ICC -0.06 to 0.60; 95% CI -1.85 to 0.85). Systolic BP had a good-to-excellent reproducibility before (ICC 0.93; 95% CI 0.81-0.98, CV% 4.2) and after exercise (ICC 0.93; 95% CI 0.81-0.97, CV% 4.2). The reproducibility of HRV indices is poor after exercise in young participants. However, the reproducibility of BP is excellent at rest and after aerobic exercise.

BACKGROUND: The elevated blood pressure (BP) and lower cardiac autonomic modulation (CAM) are associated with higher morbidity mortality risk among older adults. Although exercise is an important intervention for cardiovascular promotion, it is unclear whether combat sports training could benefit cardiovascular outcomes as much as autonomic in this population. This study compared the effects of 12 weeks of Muay Thai (MT) training against functional training (FT) on CAM and hemodynamic parameters in older adults.
METHODS: The sample consisted of 50 older adults (41 women; 66.0 ± 5.3 years old), who were equaly randomized into FT (n = 25) and MT (n = 25) intervention groups. CAM was measured by 30-min rest heart rate variability. Systolic blood pressure (SBP), diastolic blood pressure (DBP) and resting heart rate (RHR) were measured using an automatic oscillometric device. Pulse pressure (PP) and the double product (DP) were also calculated. The interventions were carried out three times a week, with 60-min length per session, during 12 consecutive weeks. The intensity of the interventions was measured using the subjective perception of exertion scale and by accelerometer. Two-factor repeated measures analysis of covariance was used for groups comparison, considering intervention group and body mass as factors. The 95% confidence interval of the difference (95%CIdif) was also calculated and the effect size was measured using partial eta squared (η2p).
RESULTS: CAM indices did not show significant changes across moments and intervention groups. In hemodynamic parameters, only in DBP was there an effect of the moment (F1,39 = 8.206; P = 0.007; η2p = 0.174, large) and interaction effect between group*moment (F1,39 = 7.950; P = 0.008; η2p = 0.169, large). Specifically, the MT group at the post-training moment showed lower DBP (P = 0.010; 95%CIdif = -13.3; -1.89) in relation to the FT group. Furthermore, the MT group showed a decrease in DBP during training (P = 0.002; 95%CIdif = -10.3; -2.6). Also, an increase in training intensity was also found over the 12 weeks in FT, with no difference between the groups.
CONCLUSIONS: After 12 weeks of MT practice there was a reduction in DBP compared to FT in older adults.
BACKGROUND: NCT03919968 Registration date: 01/02/2019.

暂无摘要。

Tobacco smoking is a risk factor for countless diseases, and smoking relapse remains a major public health concern. Subjective reports of stress by smokers are a common theme for relapse, however, the role of objective stress-related biomarkers in predicting tobacco relapse risk has been less studied. The aim of this manuscript was to review existing literature on the connection between biomarkers of stress and smoking relapse. Overall, trends indicate that blunted hypothalamic-pituitary-adrenal (HPA) responses to acute stress, larger reductions in HPA biomarkers during the initial days of abstinence during cessation (compared to pre-cessation levels), and exaggerated autonomic responses to stress predict increased risk of relapse. In addition, successful cessation is followed by changes in stress biomarkers (e.g., reductions in cortisol and heart rate, HR). This review also identifies potential modifiers, such as methodological differences, biological sex, and chronic stress, to account for heterogeneity of findings within and across studies. In addition, we identify gaps in the literature and suggest future research directions focusing on the roles of genetics and gene expression as well as the influence of neurobiological mechanisms on stress and relapse risk. Future clinical implications of this research include identifying reliable indicators of relapse risk and the potential of pharmacotherapeutic treatments to target stress response systems to correct dysregulation and potentially reduce stress-related risk of relapse.

暂无摘要。

Previous research has demonstrated a critical link between maternal mental health and infant development. However, there is limited understanding of the role of autonomic regulation in postpartum maternal mental health and infant outcomes. In the current study, we tested 76 mother-infant dyads from diverse socioeconomic backgrounds when infants were 3-months of age. We recorded simultaneous ECG from dyads while baseline EEG was collected from the infant; ECG heart rate variability (HRV) and EEG theta-beta ratio and alpha asymmetry were calculated. Dyadic physiological synchrony was also analyzed to better understand the role of autonomic co-regulation. Results demonstrated that lower maternal HRV was associated with higher self-reported maternal depression and anxiety. Additionally, mothers with lower HRV had infants with lower HRV. Maternal HRV was also associated with higher infant theta-beta ratios, but not alpha asymmetry. Exploratory analyses suggested that for mother-infant dyads with greater physiological synchrony, higher maternal HRV predicted increased infant theta-beta ratio via infant HRV. These findings support a model in which maternal mental health may influence infant neurophysiology via alterations in autonomic stress regulation and dyadic physiological co-regulation.

More than 1.5 billion people worldwide have arterial hypertension. Hypertension increases the risks of death and cardiovascular disease, such as atrial fibrillation and heart failure. The autonomic nervous system plays an essential role in hypertension development and disease progression. While lifestyle factors, such as obesity and obstructive sleep apnea, predispose to hypertension by increasing sympathetic activity, hypertension itself maintains the autonomic nervous imbalance, providing the substrate for atrial fibrillation and heart failure. Therefore, autonomic nervous system modulation either by direct targeting or indirect treatment of comorbidities has the potential to treat both hypertension and related atrial and ventricular end-organ damage. We discuss interventions for the modulation of the autonomic nervous system for hypertension and related cardiac end-organ damage, including pharmacological adrenergic beta-receptor blockade, renal denervation, carotid baroreceptor stimulation, low-level vagal stimulation, and ablation of ganglionated plexuses. In summary, the literature suggests that targeting the autonomic nervous system potentially represents a therapeutic approach to prevent atrial and ventricular end-organ damage in patients with hypertension. However, clinical trials specifically designed to test the effect of autonomic modulation on hypertension-mediated cardiac end-organ damage are scarce.

暂无摘要。

BACKGROUND: A compromised cardiac autonomic function has been found in subjects with insulin resistance related disorders such as obesity, impaired glucose tolerance (IGT) and type 2 diabetes and confers an increased risk of adverse cardiovascular outcomes. Growing evidence indicate that 1 h plasma glucose levels (1hPG) during an oral glucose tolerance test (OGTT) ≥ 155 mg/dl identify amongst subjects with normal glucose tolerance (NGT) a new category of prediabetes (NGT 1 h-high), harboring an increased risk of cardiovascular organ damage. In this study we explored the relationship between 1 h post-load hyperglycemia and cardiac autonomic dysfunction.
METHODS: Presence of cardiac autonomic neuropathy (CAN) defined by cardiovascular autonomic reflex tests (CARTs) and heart rate variability (HRV), assessed by 24-h electrocardiography were evaluated in 88 non-diabetic subjects subdivided on the basis of OGTT data in: NGT with 1 h PG < 155 mg/dl (NGT 1 h-low), NGT 1 h-high and IGT.
RESULTS: As compared to subjects with NGT 1 h-low, those with NGT 1 h-high and IGT were more likely to have CARTs defined CAN and reduced values of the 24 h time domain HVR parameters including standard deviation of all normal heart cycles (SDNN), standard deviation of the average RR interval for each 5 min segment (SDANN), square root of the differences between adjacent RR intervals (RMSSD), percentage of beats with a consecutive RR interval difference > 50 ms (PNN50) and Triangular index. Univariate analyses showed that 1hPG, but not fasting and 2hPG, was inversely associated with all the explored HVR parameters and positively with CARTs determined presence of CAN. In multivariate regression analysis models including several confounders we found that 1hPG was an independent contributor of HRV and presence of CAN.
CONCLUSIONS: Subjects with 1hPG ≥ 155 mg/dl have an impaired cardiac autonomic function.

BACKGROUND: Cardiac autonomic neuropathy (CAN) in diabetes mellitus (DM) is independently associated with cardiovascular (CV) events and CV death. Diagnosis of this complication of DM is time-consuming and not routinely performed in the clinical practice, in contrast to fundus retinal imaging which is accessible and routinely performed. Whether artificial intelligence (AI) utilizing retinal images collected through diabetic eye screening can provide an efficient diagnostic method for CAN is unknown.
METHODS: This was a single center, observational study in a cohort of patients with DM as a part of the Cardiovascular Disease in Patients with Diabetes: The Silesia Diabetes-Heart Project (NCT05626413). To diagnose CAN, we used standard CV autonomic reflex tests. In this analysis we implemented AI-based deep learning techniques with non-mydriatic 5-field color fundus imaging to identify patients with CAN. Two experiments have been developed utilizing Multiple Instance Learning and primarily ResNet 18 as the backbone network. Models underwent training and validation prior to testing on an unseen image set.
RESULTS: In an analysis of 2275 retinal images from 229 patients, the ResNet 18 backbone model demonstrated robust diagnostic capabilities in the binary classification of CAN, correctly identifying 93% of CAN cases and 89% of non-CAN cases within the test set. The model achieved an area under the receiver operating characteristic curve (AUCROC) of 0.87 (95% CI 0.74-0.97). For distinguishing between definite or severe stages of CAN (dsCAN), the ResNet 18 model accurately classified 78% of dsCAN cases and 93% of cases without dsCAN, with an AUCROC of 0.94 (95% CI 0.86-1.00). An alternate backbone model, ResWide 50, showed enhanced sensitivity at 89% for dsCAN, but with a marginally lower AUCROC of 0.91 (95% CI 0.73-1.00).
CONCLUSIONS: AI-based algorithms utilising retinal images can differentiate with high accuracy patients with CAN. AI analysis of fundus images to detect CAN may be implemented in routine clinical practice to identify patients at the highest CV risk.
BACKGROUND: This is a part of the Silesia Diabetes-Heart Project (Clinical-Trials.gov Identifier: NCT05626413).