Risk stratification of cardiac autonomic neuropathy based on multi-lag Tone–Entropy

Cardiac autonomic neuropathy (CAN) is an irreversible condition affecting the autonomic nervous system, which leads to abnormal functioning of the visceral organs and affects critical body functions such as blood pressure, heart rate and kidney filtration. This study presents multi-lag Tone–Entropy (T–E) analysis of heart rate variability (HRV) at multiple lags as a screening tool for CAN. A total of 41 ECG recordings were acquired from diabetic subjects with definite CAN (CAN+) and without CAN (CAN?) and analyzed. Tone and entropy values of each patient were calculated for different beat sequence lengths (len: 50–900) and lags (m: 1–8). The CAN? group was found to have a lower mean tone value compared to that of CAN+ group for all m and len, whereas the mean entropy value was higher in CAN? than that in CAN+ group. Leave-one-out (LOO) cross-validation tests using a quadratic discriminant (QD) classifier were applied to investigate the performance of multi-lag T–E features. We obtained 100 % accuracy for tone and entropy with len = 250 and m = {2, 3} settings, which is better than the performance of T–E technique based on lag m = 1. The results demonstrate the usefulness of multi-lag T–E analysis over single lag analysis in CAN diagnosis for risk stratification and highlight the change in autonomic nervous system modulation of the heart rate associated with cardiac autonomic neuropathy.     

Heart rate variability and nonlinear dynamic analysis in patients with stress-induced cardiomyopathy

Complexity-based analyses may quantify abnormalities in heart rate variability (HRV). The aim of this study was to investigate the clinical and prognostic significances of dynamic HRV changes in patients with stress-induced cardiomyopathy Takotsubo syndrome (TS) by means of linear and nonlinear analysis. Patients with TS were included in study after complete noninvasive and invasive cardiovascular diagnostic evaluation and compared to an age and gender matched control group of healthy subjects. Series of R–R interval and of ST–T interval values were obtained from 24-h ECG recordings after digital sampling. HRV analysis was performed by ‘range rescaled analysis’ to determine the Hurst exponent, by detrended fluctuation analysis to quantify fractal long-range correlation properties, and by approximate entropy to assess time-series predictability. Short- and long-term fractal-scaling exponents were significantly higher in patients with TS in acute phases, opposite to lower approximate entropy and Hurst exponent, but all variables normalized in a few weeks. Dynamic HRV analysis allows assessing changes in complexity features of HRV in TS patients during the acute stage, and to monitor recovery after treatment, thus complementing traditional ECG and clinically analysis.     

Decline in suicidal ideation among patients with MDD is preceded by decline in depression and hopelessness

BACKGROUND: Suicidal ideation is likely to represent a phase preceding suicidal acts among most suicidal patients with major depressive disorder (MDD). Factors predicting reversal of the suicidal process are unknown. Our aim was to test the hypothesis that a decline in suicidal ideation is preceded by a decline in hopelessness among patients with MDD. METHOD: Of the 269 Vantaa Depression Study patients with DSM-IV MDD, 103 patients scored > or = 6 points at baseline on the Scale for Suicidal Ideation (SSI). Seventy of these patients were followed-up weekly either until they scored zero points on the SSI, or up to 26 weeks. RESULTS: The median duration for a decline of suicidal ideation to zero was 2.2 months after baseline. The level of baseline suicidal ideation, depressive symptoms, and the presence of any personality disorder predicted duration of suicidal ideation. A decline in both depression (BDI) and hopelessness (HS) independently predicted a decline in suicidal ideation. LIMITATIONS: Due to study design, we do not know if suicidal ideation relapsed after the first time the patient reached zero score in the SSI. CONCLUSIONS: Among patients with major depressive disorder having suicidal ideation, the decline in suicidal ideation is independently predicted by preceding declines in the levels of both depressive symptoms as well as hopelessness. The findings are consistent with possible causal roles of declines in depression and hopelessness in reversing the suicidal process.     

Association of cardiac autonomic neuropathy with alteration of sympatho-vagal balance through heart rate variability analysis

Early sub-clinical assessment of severity of cardiac autonomic neuropathy (CAN) and intervention are of prime importance for risk stratification and early treatment in preventing sudden death due to silent myocardial infarction. The Ewing battery is currently the diagnostic tool of choice but is unable to detect sub-clinical disease and requires patient cooperation. Time and frequency domain analysis have several shortcomings including sensitivity to recording length, respiratory activity and non-stationarities in the ECG signal. An important step forward is to have a non-invasive method of detecting CAN that is robust against these shortcomings and has a higher sensitivity for the presence of both sub-clinical and overt clinical disease. This study presents a novel parameter, tone–entropy (T–E) that analyses heart rate variability (HRV) of 20 min lead II ECG recordings. Tone (T) represents sympatho-vagal balance and entropy (E) the autonomic regularity activity. Thirteen normal subjects without (CAN?) and 21 with CAN (CAN+) participated in this study. Among 21 CAN+ subjects, 13 are early CAN+ (eCAN+), eight are definite CAN+ (dCAN+) according to autonomic nervous system function tests as described by Ewing. The results showed that tone was higher and the entropy was lower in the dCAN+ group (T = ?0.033 to ?0.010 and E = 1.73–2.24) compared with the eCAN+ (T = ?0.0927 to ?0.0311 and E = 2.0–2.65) and normal (T = ?0.128 to ?0.0635 and E = 2.64–3.15) group. The research verified that T–E is a suitable method to determine the presence of CAN that correctly identifies experimentally induced changes in cardiac function akin to parasympathetic and sympathetic dysfunction and differentiates between stages in CAN disease progression identified using the Ewing battery.     

Assessment of heart rate variability derived from finger-tip photoplethysmography as compared to electrocardiography

Heart rate variability (HRV) is traditionally derived from RR interval time series of electrocardiography (ECG). Photoplethysmography (PPG) also reflects the cardiac rhythm since the mechanical activity of the heart is coupled to its electrical activity. Thus, theoretically, PPG can be used for determining the interval between successive heartbeats and heart rate variability. However, the PPG wave lags behind the ECG signal by the time required for transmission of pulse wave. In this study, finger-tip PPG and standard lead II ECG were recorded for five minutes from 10 healthy subjects at rest. The results showed a high correlation (median = 0.97) between the ECG-derived RR intervals and PPG-derived peak-to-peak (PP) intervals. PP variability was accurate (0.1 ms) as compared to RR variability. The time domain, frequency domain and Poincaré plot HRV parameters computed using RR interval method and PP interval method showed no significant differences (p < 0.05). The error analysis also showed insignificant differences between the HRV indices obtained by the two methods. Bland-Altman analysis showed high degree of agreement between the two methods for all the parameters of HRV. Thus, HRV can also be reliably estimated from the PPG based PP interval method.     

Assessment of heart rate variability derived from finger-tip photoplethysmography as compared to electrocardiography

Heart rate variability (HRV) is traditionally derived from RR interval time series of electrocardiography (ECG). Photoplethysmography (PPG) also reflects the cardiac rhythm since the mechanical activity of the heart is coupled to its electrical activity. Thus, theoretically, PPG can be used for determining the interval between successive heartbeats and heart rate variability. However, the PPG wave lags behind the ECG signal by the time required for transmission of pulse wave. In this study, finger-tip PPG and standard lead II ECG were recorded for five minutes from 10 healthy subjects at rest. The results showed a high correlation (median = 0.97) between the ECG-derived RR intervals and PPG-derived peak-to-peak (PP) intervals. PP variability was accurate (0.1 ms) as compared to RR variability. The time domain, frequency domain and Poincaré plot HRV parameters computed using RR interval method and PP interval method showed no significant differences (p < 0.05). The error analysis also showed insignificant differences between the HRV indices obtained by the two methods. Bland-Altman analysis showed high degree of agreement between the two methods for all the parameters of HRV. Thus, HRV can also be reliably estimated from the PPG based PP interval method.     

Suicidal behavior-related hospitalizations among pregnant women in the USA, 2006–2012

Suicide is one of the leading causes of maternal mortality in many countries, but little is known about the epidemiology of suicide and suicidal behavior among pregnant women in the USA. We sought to examine trends and provide nationally representative estimates for suicidal behavior (including suicidal ideation and suicide and self-inflicted injury) among pregnant women from 2006 to 2012 in the USA. Pregnant women aged 12–55 years were identified through pregnancy- and delivery-related hospitalization records from the National (Nationwide) Inpatient Sample. Suicidal behavior was identified by the International Classification of Diseases, Ninth Revision, Clinical Modification codes. Annual, nationwide estimates and trends were determined using discharge and hospital weights. The prevalence of suicidal ideation more than doubled from 2006 to 2012 (47.5 to 115.0 per 100,000 pregnancy- and delivery-related hospitalizations), whereas the prevalence of suicide and self-inflicted injury remained stable. Nearly 10 % of suicidal behavior occurred in the 12–18-year group, showing the highest prevalence per 100,000 pregnancy- and delivery-related hospitalizations (158.8 in 2006 and 308.7 in 2012) over the study period. For suicidal ideation, blacks had higher prevalence than whites; women in the lowest income quartile had the highest prevalence. Although the prevalence of suicidal behavior was higher among hospitalizations with depression diagnoses, more than 30 % of hospitalizations were for suicidal behavior without depression diagnoses. Our findings highlight the increasing burden and racial differences in suicidal ideation among US pregnant women. Targeted suicide prevention efforts are needed for high-risk pregnant women including teens, blacks, and low-income women.     

The effect of perceived body weight on suicidal ideation among a representative sample of US adolescents

There is no published report on the sex differences in the prospective influence of perceived body weight on suicidal ideation in adolescents. To examine sex differences in the longitudinal relationship between perceived body weight and suicidal ideation among a representative sample of US middle and high school students. Two waves of longitudinal data from 7th–12th grade US adolescents (N = 4,717) in the National Longitudinal Study of Adolescent Health were analyzed using hierarchical multivariable logistic regression for suicidal ideation 1 year after perceived body weight was measured. Overweight perception significantly increased the risk for suicidal ideation in girls (adjusted odds ratio in the full model = 1.41, p < .05) but not in boys after controlling for previously well-documented risk factors of suicidal ideation. Overweight perception appears to increase the risk for suicidal ideation in girls. It is important to address perceived body weight among girls in suicide prevention interventions.     

Associations among depression,suicidal behavior,and quality of life in patients with human immunodeficiency virus

AIM: To investigate the potential associations among major depression, quality of life, and suicidal behavior in human immunodeficiency virus(HIV) patients. METHODS: A detailed MEDLINE search was carried out to identify all articles and book chapters in English published from January 1995 to January 2015. RESULTS: Based on the main findings, the prevalence of major depressive disorder(MDD) ranged from 14.0% to 27.2%. Furthermore, the prevalence of suicidal ideation varied from 13.6% to 31.0% whereas, attempted suicides were reported to range from 3.9% to 32.7%. Interestingly, various associated risk factors for both depression and suicide were identified in HIV patients. Finally, consistent associations were reported among MDD, suicidal ideation, and poor quality of life in individuals living with HIV. CONCLUSION: Although additional studies are needed to elucidate this complex association, our results suggest the importance of early detection of both MDD and suicidality in patients living with HIV.     

Comparison of pulse rate variability with heart rate variability during obstructive sleep apnea

We investigate whether pulse rate variability (PRV) extracted from finger photo-plethysmography (Pleth) waveforms can be the substitute of heart rate variability (HRV) from RR intervals of ECG signals during obstructive sleep apnea (OSA). Simultaneous measurements (ECG and Pleth) were taken from 29 healthy subjects during normal (undisturbed sleep) breathing and 22 patients with OSA during OSA events. Highly significant (p<0.01) correlations (1.0>r>0.95) were found between heart rate (HR) and pulse rate (PR). Bland-Altman plot of HR and PR shows good agreement (<5% difference). Comparison of 2 min recording epochs demonstrated significant differences (p<0.01) in time, frequency domains and complexity analysis, between normal and OSA events using PRV as well as HRV measures. Results suggest that both HRV and PRV indices could be used to distinguish OSA events from normal breathing during sleep. However, several variability measures (SDNN, RMSSD, HF power, LF/HF and sample entropy) of PR and HR were found to be significantly (p<0.01) different during OSA events. Therefore, we conclude that PRV provides accurate inter-pulse variability to measure heart rate variability under normal breathing in sleep but does not precisely reflect HRV in sleep disordered breathing.     

A prospective study of thoughts of self-harm and suicidal ideation during the postpartum period in women with mood disorders

Individuals with mood disorders are at higher risk for self-harm and suicidal ideation than other psychiatric group. However, the risk of self-harm and suicidal ideation after pregnancy for women with mood disorders is unknown. This investigation assessed the prevalence of thoughts of self-harm and suicidal ideation during the 1-year postpartum period in women with major depressive disorder or bipolar II disorder. Data were collected between June 2005 and March 2010 from a convenience sample of women participating in a study on the course of mood disorders during pregnancy and postpartum. Participant diagnosis was confirmed using the Structured Clinical Interview for DSM-IV. Thoughts of self-harm were assessed using the Edinburgh Postnatal Depression Scale item 10 and suicidal ideation was assessed using the Hamilton Depression Rating Scale item 3. During the 1-year postpartum period, 16.97 % reported thoughts of self-harm while 6.16 % reported suicidal ideation. Further, those reporting thoughts of self-harm or suicidal ideation postpartum also reported higher levels of depression and hypomanic symptoms. We found that a number of women in our sample of women with a diagnosed mood disorder report experiencing thoughts of self-harm and suicidal ideation during the postpartum.     

Multivariate short-term heart rate variability: a pre-diagnostic tool for screening heart disease

This study has aimed to develop a novel pre-diagnostic tool for primary care screening of heart disease based on multivariate short-term heart rate variability (HRV) analyzed by linear (time and frequency domain) and nonlinear methods (compression entropy (CE), detrended fluctuation analysis (DFA), Poincaré plot analysis, symbolic dynamics) applied to 5-min ECG segments. Firstly, we applied HRV analysis to separate healthy subjects (REF) from heart disease patients (PAT). Then to optimize the results, we subdivided both groups according to gender: REF (♂ = 78, ♀ = 53) versus PAT (♂ = 378, ♀ = 115). Finally, we divided REF and PAT into two age subgroups (30–50 years vs. 51-70 years of age) to consider the influence of age on HRV. Heart disease patients were classified using a scoring system based on cut-off values calculated from all HRV indices obtained from the REF. After combining the optimum indices from all different analyzing methods, sensitivities of more than 72% and a specificity of 100% in all subgroups were revealed. Nonlinear indices proved to be better for discriminating heart disease patients from healthy subjects. Multivariate short-term HRV, analyzed by both linear and nonlinear methods appears to be a suitable pre-diagnostic tool for screening heart disease in primary care settings.     

Does comorbid Social Anxiety Disorder impact the clinical presentation of principal Major Depressive Disorder?

BACKGROUND: Although previous research has examined comorbidity in principal Social Anxiety Disorder (SAD), few studies have examined the disorders for which those with comorbid SAD seek treatment. Further, studies have shown that depressive disorders often are associated with SAD, but few have examined the clinical characteristics of patients with this particular comorbidity. METHOD: The current study examined the prevalence of various principal Axis I disorders in 577 individuals diagnosed with comorbid SAD. RESULTS: Consistent with previous research, Major Depressive Disorder (MDD) was the most frequent principal diagnosis in patients with comorbid SAD. Those with principal MDD and comorbid SAD (MDD-SAD) were compared to those with MDD without SAD (MDD) on demographic and clinical characteristics. Patients with MDD-SAD versus those with MDD were more severe in terms of social functioning, duration of depressive episode, suicidal ideation, time out of work, presence of current alcohol abuse/dependence, and age of onset of MDD. Social functioning, duration of episode, suicidal ideation, and age of onset of MDD remained significant even after controlling for additional comorbid disorders. CONCLUSIONS: Findings suggest the need for future research to determine how treatments could be adapted for this commonly occurring comorbidity.     

The development of a novel high-precision major depressive disorder screening system using transient autonomic responses induced by dual mental tasks

12.6% of major depressive disorder (MDD) patients have suicide intent, while it has been reported that 43% of patients did not consult their doctors for MDD, automated MDD screening is eagerly anticipated. Recently, in order to achieve automated screening of MDD, biomarkers such as multiplex DNA methylation profiles or physiological method using near infra-red spectroscopy (NIRS) have been studied, however, they require inspection using 96-well DNA ELIZA kit after blood sampling or significant cost. Using a single-lead electrocardiography (ECG), we developed a high-precision MDD screening system using transient autonomic responses induced by dual mental tasks. We developed a novel high precision MDD screening system which is composed of a single-lead ECG monitor, analogue to digital (AD) converter and a personal computer with measurement and analysis program written by LabView programming language. The system discriminates MDD patients from normal subjects using heat rate variability (HRV)-derived transient autonomic responses induced by dual mental tasks, i.e. verbal fluency task and random number generation task, via linear discriminant analysis (LDA) adopting HRV-related predictor variables (hear rate (HR), high frequency (HF), low frequency (LF)/HF). The proposed system was tested for 12 MDD patients (32?±?15?years) under antidepressant treatment from Shizuoka Saiseikai General Hospital outpatient unit and 30 normal volunteers (37?±?17?years) from Tokyo Metropolitan University. The proposed system achieved 100% sensitivity and 100% specificity in classifying 42 examinees into 12 MDD patients and 30 normal subjects. The proposed system appears promising for future HRV-based high-precision and low-cost screening of MDDs using only single-lead ECG.     

Impaired parasympathetic augmentation under relaxation in patients with depression as assessed by a novel non-contact microwave radar system

In order to conduct objective screening of major depressive disorder (MDD), a chair-based system was developed which measures alteration of parasympathetic activation induced by relaxing audio-visual exposure in a non-contact way using dual compact-radars attached to a chair back. The system determines autonomic activation by calculating low (LF) and high frequency (HF) components of heart rate variability (HRV) before and after relaxation. Forty-one subjects (28 normal subjects, 13 MDD subjects) were exposed to relaxing natural sounds and images for 10 min. In order to determine the possibility of MDD from autonomic alteration induced by relaxing, linear discriminant analysis was conducted using LF and HF before and after relaxation. F-test revealed the significance of derived linear discriminant function (p?相似文献   

Depression and suicidality in HIV/AIDS in China

BACKGROUND: This pilot study examined rates of major depression and suicidality and their associations with daily functioning in HIV infected (HIV+) and uninfected (HIV-) persons in China. METHOD: HIV+ participants (N=28) and demographically matched HIV- controls (N=23) completed the Chinese Composite International Diagnostic Interview to determine lifetime rates of major depressive disorder (MDD) and suicidality. Current mood and suicidal ideation were assessed with the Beck Depression Inventory-I. The impact of depression and HIV infection on daily functioning was measured by an Activity of Daily Living questionnaire. RESULTS: Mean duration of known HIV+ status was 2 years. Almost 79% (n=22) of HIV+ but just 4% (n=1) of HIV- groups reported lifetime major depression. Of the 22 HIV+ individuals with lifetime MDD, only one had onset before learning of HIV status. The remainder developed MDD within 6 months after testing HIV positive. In those HIV+ subjects who met MDD criteria after HIV diagnosis, only two (9%) had received depression treatment, yet four (18%) had persisting active suicidal thoughts. Depression and HIV+ status independently predicted worse daily functioning. LIMITATIONS: Representativeness is limited in this small sample of convenience. CONCLUSION: This preliminary study presents evidence of high rates of major depression and suicidality in HIV-infected persons in China. Despite this, few had sought mental health assistance, suggesting a need to increase awareness of psychiatric comorbidity and access to mental health services.     

Nonlinear analysis of heart rate variability of healthy subjects and patients with chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is one of the causes of mortality worldwide with an increasing prevalence. Heart rate variability (HRV) reflects the regulation mechanism of the cardiac activity by the autonomic nervous system. The assessment of HRV by using nonlinear methods is more sensitive for the detection of complexity when compared to linear methods. This study aims to get information about the autonomic dysfunction occurred in patients with COPD by analysing the complexity of HRV. Electrocardiogram signals recorded from healthy subjects, patients with moderate COPD and severe COPD (eight subjects per group) were analysed. The HRV signals were acquired from ECG signals. Signals were reconstructed in the phase space and largest Lyapunov exponent (LLE), correlation dimension, Hurst exponent and approximate entropy (ApEn) values were calculated. It has seen that for the patients with COPD LLE, correlation dimension, Hurst exponent and ApEn values were less than control group. According to this, HRV complexity decreases in the presence of COPD. However, there is no significant difference between COPD groups and the severity of COPD has no effect on the chaoticity of the system. The results revealed that autonomic dysfunction occurred in patients with COPD is associated with reduced HRV complexity.     

Optimal timing in screening patients with congestive heart failure and healthy subjects during circadian observation

Congestive heart failure (CHF) is a major medical challenge in developed countries. In order to screen patients with CHF and healthy subjects during circadian observation, accurate judgment and fast response are imperative. In this study, optimal timing during circadian observation via the heart rate variability (HRV) was sought. We tested 29 CHF patients and 54 healthy subjects in the control group from the interbeat interval databases of PhysioBank. By invoking the α1 parameter in detrended fluctuation analysis of HRV, we found that it could be used as an indicator to screen the patients with CHF and subjects in normal sinus rhythm (NSR) under Kruskal–Wallis test. By invoking Fano factor, the optimal timing to screen CHF patients and healthy subjects was found to be from 7 PM to 9 PM during the circadian observation. In addition, this result is robust in a sense that the same result can be achieved by using different ECG recording lengths of 2, 5, 10, … , and 120 min, respectively. Furthermore, a support vector machine was employed to classify CHF and NSR with α1 parameter of a moving half-hour ECG recordings via leave-one-out cross validation. The results showed that the superlative screening performance was obtained in the 7 pm–9 pm period during circadian observation. It is believed that this result of optimal timing will be helpful in the non-invasive monitoring and screening of CHF patients and healthy subjects in the clinical practice.     

Combining classical HRV indices with wavelet entropy measures improves to performance in diagnosing congestive heart failure

In this study, best combination of short-term heart rate variability (HRV) measures are sought for to distinguish 29 patients with congestive heart failure (CHF) from 54 healthy subjects in the control group. In the analysis performed, in addition to the standard HRV measures, wavelet entropy measures are also used. A genetic algorithm is used to select the best ones from among all possible combinations of these measures. A k-nearest neighbor classifier is used to evaluate the performance of the feature combinations in classifying these two groups. The results imply that two combinations of all HRV measures, both of which include wavelet entropy measures, have the highest discrimination power in terms of sensitivity and specificity values.     

中重度抑郁症患者心电图及心率变异性分析

目的:探讨中重度抑郁症患者心电图及心率变异性特点,为临床评估中重度抑郁症心脏自主神经功能变化提供依据.方法:选择2018年6月至2019年12月就诊于湖南省脑科医院的中重度抑郁症患者38例为研究组,32例健康志愿者为对照组,比较两组心电图异常率及心率变异性,并统计分析各指标之间的差异.结果:研究组心电图异常ST-T改变...