Heart rate variability during motor and cognitive tasks in females with major depressive disorder.
ABSTRACT: Research indicates that major depressive disorder (MDD) is associated with alterations in autonomic control, particularly cardiac control as measured by heart rate variability (HRV). In this preliminary study, we investigated the neural correlates of autonomic control by measuring both HRV and associated brain activity during the performance of mildly stressful tasks. Medically healthy female subjects with MDD (N=10) and healthy controls (N=7) underwent H(2)(15)O-positron emission tomography (PET) and electrocardiographic ECG recording while performing a handgrip motor task and an n-back task. Indices of HRV were calculated and correlated with regional cerebral blood flow (rCBF). Differences in the rCBF and HRV correlations between depressed and healthy subjects were evident in both the medial and lateral orbital cortices. In addition, these areas appeared to be involved in different facets of autonomic control with regard to sympathetic or parasympathetic dominance of cardiac control. These results are consistent with the known roles of networks within the orbital cortex in both autonomic control and the pathophysiology of MDD.
Project description:Electrophysiology, behavioral, and neuroimaging studies have revealed sex-related differences in autonomic cardiac control, as reflected in measurements of heart rate variability (HRV). Imaging studies indicate that the neurobiological correlates of autonomic nervous system (ANS) function can be investigated by measuring indices of HRV during the performance of mildly strenuous motor tasks or mildly stressful cognitive tasks. In this preliminary study, fifteen male and seven female healthy subjects underwent H(2)(15)O-positron emission tomography (PET) and electrocardiograph (ECG) recording while performing a handgrip motor task and an n-back task. Indices of HRV were calculated and correlated with regional cerebral blood flow (rCBF). We hypothesized that sex differences would be evident in brain regions known to participate in autonomic regulation: the anterior insula, the anterior cingulate cortex, the orbitofrontal cortex, and the amygdala. Our study found that associations between rCBF and parasympathetic indices differed significantly between female and male subjects in the amygdala. Females showed a positive correlation between rCBF and parasympathetic indices while males exhibited negative correlations. This differential correlation of amygdala rCBF and parasympathetic activity between males and females may reflect differences in parasympathetic/sympathetic balance between sexes, consistent with known sexual dimorphism in the amygdala and closely related structures such as the hypothalamus. These preliminary imaging results are consistent with earlier reports of significant correlation between brain activity and HRV, and extend these findings by demonstrating prominent sex differences in the neural control of the ANS. While the generalizability of our results was limited by the small size of the study samples, the relatively robust effect size of the differences found between groups encourages further work in larger samples to characterize sex differences in the neural correlates of autonomic arousal.
Project description:The regulation of the autonomic nervous system (ANS) can improve cognitive function in major depressive disorders (MDD). Heart rate variability (HRV) derives from the dynamic control of the ANS and reflects the balance between the activities of the sympathetic and parasympathetic nervous systems by measuring tiny changes in adjacent heart beats. Task-related HRV may reflect the association between the flexibility of cognition and ANS function. The study was to investigate the neural mechanism of interactions between ANS and cognitive function in MDD with Magnetoencephalography (MEG) measurements. Participants included 20 MDD patients and 18 healthy controls (HCs). All participants were measured with a go/no-go task MEG. HRV indices, the standard deviation of the average normal-to-normal (NN) interval calculated over short periods (SDANN) and the square root of the mean squared differences of successive NN intervals (RMSSD), were derived from the raw MEG data. Results showed that MDD patients showed decreased SDANN and RMSSD. In MDD patients, both resting-state and task-related RMSSD were related to inhibitory and control dysfunction. In the go/no-go task, many areas in the prefrontal cortex (PFC) are responsible for an individual's inhibitory function. A brain MEG functional connectivity analysis revealed that there were significant differences in four brain regions within the prefrontal cortex (PFC) between MDD patients and HCs. Task-related RMSSD in HCs were related to the functional connectivity between the left middle frontal gyrus and the anterior cingulate cortex (ACC), while in MDD patients, these values were not related to the above functional connectivity but were related to the functional connectivity between the left middle frontal gyrus and insula. However, the resting-state RMSSD value was not related to these significant difference functional connectivity networks in all participants. It concludes that the decreased task-related HRV is associated with inhibitory dysfunction through functional inter-region connectivity in the PFC in MDD, and the task-related HRV can be used as an index of the association between MDD and autonomic dysregulation.
Project description:Evidence indicates that reduced cardiac vagal (parasympathetic) tone, a robust cardiovascular risk factor, is a trait vulnerability marker of major depressive disorder (MDD). The Ser205/Ser205 genotype of the functional polymorphism (Ser205Leu) of the nerve growth factor receptor (NGFR), also called p75 neurotrophin receptor (p75(NTR)), gene is reported to increase the risk of MDD. Here, we hypothesized that the NGFR Ser205Leu polymorphism may have an effect on vagal control. A sample of 810 healthy, drug-free, unrelated Han Chinese (413 males, 397 females; mean age 35.17?±?8.53 years) was included in the NGFR genotyping. Short-term heart rate variability (HRV) was used to assess vagus-mediated autonomic function. Potential HRV covariates, such as mood/anxiety status and serum metabolic parameters, were assessed. Homozygotes of the Ser205 allele had significantly lower high frequency power and root mean square of successive heartbeat interval differences, both HRV indices of vagal modulation, compared to Leu205 allele carriers. Even after adjusting for relevant confounders, these associations remained significant. Further stratification by sex revealed that the associations were observed only in males. Our results implicate that decreased parasympathetic activity is associated with the NGFR Ser205/Ser205 genotype in a gender-specific manner, suggesting a potential role of NGFR polymorphism in modulating cardiac autonomic function.
Project description:Duchenne Muscular Dystrophy (DMD) is characterized by progressive muscle weakness that can lead to disability. Owing to functional difficulties faced by individuals with DMD, the use of assistive technology is essential to provide or facilitate functional abilities. In DMD, cardiac autonomic dysfunction has been reported in addition to musculoskeletal impairment. Consequently, the objective was to investigate acute cardiac autonomic responses, by Heart Rate Variability (HRV), during computer tasks in subjects with DMD.HRV was assessed by linear and nonlinear methods, using the heart rate monitor Polar RS800CX chest strap Electrocardiographic measuring device. Then, 45 subjects were included in the group with DMD and 45 in the healthy Typical Development (TD) control group. They were assessed for twenty minutes at rest sitting, and five minutes after undergoing a task on the computer.Individuals with DMD had a statistically significant lower parasympathetic cardiac modulation at rest when compared to the control group, which further declined when undergoing the tasks on the computer.DMD patients presented decreased HRV and exhibited greater intensity of cardiac autonomic responses during computer tasks characterized by vagal withdrawal when compared to the healthy TD control subjects.
Project description:Cardiac autonomic neuropathy in type 2 dibetes mellitus (T2DM) patients is frequent and associated with high cardiovascular mortality. Heart rate variability (HRV) is the gold standard to measure cardiac autonomic neuropathy. We aimed to conduct a systematic review and meta-analysis to evaluate the impact of T2DM on HRV parameters.The PubMed, Cochrane Library, Embase and Science Direct databases were searched on 1st October 2017 using the keywords "diabetes" AND ("heart rate variability" OR "HRV"). Included articles had to report HRV parameters in T2DM patients and healthy controls measured during 24 hours with a Holter-electrocardiogram. Measurements of HRV retieved were: RR-intervals (or Normal to Normal intervals-NN), standard deviation of RR intervals (SDNN), percetange of adjacent NN intervals differing by more than 50 milliseconds (pNN50), square root of the mean squared difference of successive RR intervals (RMSSD), total power, Low Frequency (LF), High Frequency (HF) and LF/HF ratio, as per Task Force recommendations.We included twenty-five case-control studies with 2,932 patients: 1,356 with T2DM and 1,576 healthy controls. T2DM patients had significantly (P<0.01) lower RR-intervals (effect size = -0.61; 95%CI -1.21 to -0.01), lower SDNN (-0.65; -0.83 to -0.47), lower RMSSD (-0.92; -1.37 to -0.47), lower pNN50 (-0.46; -0.84 to -0.09), lower total power (-1.52; -2.13 to -0.91), lower LF (-1.08; -1.46 to -0.69]), and lower HF (-0.79; -1.09 to -0.50). LF/HF did not differ between groups. Levels of blood glucose and HbA1c were associated with several HRV parameters, as well as Time from diagnosis of T2DM.T2DM was associated with an overall decrease in the HRV of T2DM patients. Both sympathetic and parasympathetic activity were decreased, which can be explained by the deleterious effects of altered glucose metabolism on HRV, leading to cardiac autonomic neuropathy.
Project description:BACKGROUND:The current method to evaluate major depressive disorder (MDD) relies on subjective clinical interviews and self-questionnaires. OBJECTIVE:Autonomic imbalance in MDD patients is characterized using entropy measures of heart rate variability (HRV). A machine learning approach for screening depression based on the entropy is demonstrated. METHODS:The participants experience five experimental phases: baseline (BASE), stress task (MAT), stress task recovery (REC1), relaxation task (RLX), and relaxation task recovery (REC2). The four entropy indices, approximate entropy, sample entropy, fuzzy entropy, and Shannon entropy, are extracted for each phase, and a total of 20 features are used. A support vector machine classifier and recursive feature elimination are employed for classification. RESULTS:The entropy features are lower in the MDD group; however, the disease does not have a significant effect. Experimental tasks significantly affect the features. The entropy did not recover during REC1. The differences in the entropy features between the two groups increased after MAT and showed the largest gap in REC2. We achieved 70% accuracy, 64% sensitivity, and 76% specificity with three optimal features during RLX and REC2. CONCLUSION:Monitoring of HRV complexity changes when a subject experiences autonomic arousal and recovery can potentially facilitate objective depression recognition.
Project description:Heart rate variability (HRV) reflects beat-to-beat variability in the heart rate due to the dynamic interplay of the sympathetic and parasympathetic nervous systems. HRV is considered an index of the functional status of the autonomic nervous system. A decrease in HRV is thus observed in individuals with autonomic dysfunction. Abnormal HRV has been reported in a range of mental disorders. In this review, we give an overview of HRV in patients with major depressive disorder (MDD), schizophrenia, and posttraumatic stress disorder (PTSD), one of whose core symptoms is cognitive dysfunction. The association between HRV and cognitive function is highlighted in this review. This review consists of three main sections. In the first section, we examine how HRV in patients with MDD, schizophrenia, and PTSD is characterized, and how it is different when compared to that in healthy controls. In the second section, beyond the heart itself, we discuss the intimate connection between the heart and the brain, focusing on how HRV interacts with quantitative electroencephalography (qEEG) in the context of physiological changes in the sleep cycle. Lastly, we finish the review with the examination of the association between HRV and cognitive function. The overall findings indicate that the reduction in HRV is one of main manifestations in MDD, schizophrenia, and PTSD, and also more generally HRV is closely linked to the change in qEEG and also to individual differences in cognitive performance.
Project description:Major depressive disorder (MDD) has been associated with abnormalities in cortical thickness and autonomic function. Adolescence is a time notable for brain development and MDD onset. In healthy adolescents, greater resting state vagal activity (RVA) is associated with lower cortical thickness. The relationship between brain structural thickness and RVA in adolescents with MDD has not previously been studied. This secondary analysis drew on a sample of 37 non-depressed controls and 53 adolescents with MDD. Resting state heart rate and two indices of RVA (HF-HRV and RMSSD) were recorded during a neuroimaging session. Cortical thickness within fronto-limbic regions of interest was measured using Freesurfer analysis of T1-weighted high-resolution structural images. Self-reports of depression severity showed a significant interaction with cortical thickness of the right insula in predicting RMSSD [t?=?2.22, P=0.030, ??=?5.44; model fit of the interaction term as indicated by the 'Bayes Factor' (BF): 7.58] and HF-HRV (t?=?2.09, P=0.041, ??=?4.72; BF: 7.94). Clinician ratings of depression severity showed further interactions. Findings underscore the important relationships between RVA and cortical development, suggesting two possible explanations: (i) in adolescent MDD, greater fronto-limbic thickness is compensatory for deficits in autonomic regulation or (ii) increased autonomic arousal results in delayed fronto-limbic maturation. Longitudinal research is necessary to further clarify the nature of the relationship between autonomic functioning and cortical development.
Project description:Major depressive disorder (MDD) is associated with changes in autonomic nervous system (ANS) and cognitive impairment. Heart rate variability (HRV) and Pulse pressure (PP) parameters reflect influences of the sympathetic and parasympathetic nervous system. Cortisol exerts its greatest effect on the hippocampus, a brain area closely related to cognitive function. This study aims to examine the effect of HRV, PPG, salivary cortisol levels, and cognitive function in MDD patients by using noninvasive techniques. We have recruited MDD patients, diagnosed based on DSM-V-TR criteria compared with healthy control subjects. Their HRV and PP were measured by electrocardiogram (ECG) and photoplethysmography (PPG). Salivary cortisol levels were collected and measured on the same day. MDD patients exhibited elevated values of mean HR, standard deviation of HR (SDHR), low frequency (LF) power, low frequency/high frequency (LF/HF) ratio, mean PP, standard deviation of pulse pressure (SDPP), and salivary cortisol levels. Simultaneously, they displayed lower values of mean of R-R intervals (mean NN), standard deviation of R-R intervals (SDNN), high frequency (HF) power, and WCST scores. Results have shown that the ANS of MDD patients were dominated by the sympathetic activity and that they have cognitive deficits especially in the domain of executive functioning.
Project description:Purpose:The present study aimed to examine association between inflammatory and endothelial function biomarkers and indices of cardiac autonomic control in T2DM patients. Methods:50 T2DM patients were recruited for this study. For cardiac autonomic function, cardiovascular autonomic reflex tests (CARTs) and heart rate variability (HRV) analysis was performed. Blood samples were collected for evaluating inflammatory and endothelial function biomarkers. Multivariable linear regression analysis adjusted for diabetes duration, glycemic control, waist circumference, hypertension, dyslipidemia, metformin, and statins was performed to examine the association between the biomarkers and cardiac autonomic function parameters. Results:Interleukin-6 was inversely related to total power (p =?.009) and low frequency power (p =?.04). Interleukin-18 and high sensitivity C-reactive protein inversely correlated with measures of cardiac vagal control (p?<?.05). Both nitric oxide and endothelial nitric oxide synthase were positively linked with cardiac vagal control indices (p?<?.05) whereas endothelin-1 did not show any independent association with cardiac autonomic function parameters. Conclusions:Biomarkers of inflammation and endothelial function are associated with measures of cardiac vagal control and global HRV which suggest that there is some pathophysiological link between subclinical inflammation, endothelial dysfunction and cardiac autonomic dysfunction in T2DM.