Heart rate variability and cardiac autonomic function in men with chronic alcohol dependence

Written exposure therapy for veterans with co-occurring substance use disorders and PTSD: Study design of a randomized clinical trial

There are high rates of posttraumatic stress disorder (PTSD) among treatment-seeking veterans with substance use disorders (SUD). While addiction programs traditionally do not address PTSD, there is evidence that trauma treatments for individuals with this comorbidity have improved PTSD and SUD outcomes. Written exposure therapy (WET), a five-session evidence-based psychotherapy (EBP) for PTSD, has high patient satisfaction, and lower dropout compared to other EBPs for PTSD. WET may be ideally suited for clinical settings that may not have the trauma expertise found in PTSD specialty clinics, given it requires less training time, treatment sessions, preparation time, and therapist involvement than existing EBPs, and no homework assignments. This paper describes the design, methodology, and protocol of a randomized clinical trial to evaluate whether treatment as usual (TAU) plus WET (n = 51) is superior to TAU plus a neutral topic writing condition (n = 51) on both PTSD and addiction outcomes for veterans in SUD treatment. The primary hypothesis is that participants assigned to TAU+WET, compared to those in TAU+ neutral topic writing, will report reduced symptoms of PTSD. The secondary hypothesis is that veterans receiving WET will have greater decreases in number of days of substance use compared to TAU+ neutral topic controls at follow-up. Assessments will take place at baseline, post-treatment, 8-week, and 12-week follow-up. Exploratory aims will examine the association between heart rate variability and treatment outcomes. If results prove promising, they will support WET as an effective brief, easy to disseminate, adjunct to current SUD treatment for veterans with comorbid PTSD. Trial registration: ClinicalTrials.gov ID NCT05327504.

How to properly evaluate cardiac vagal tone in oncology studies: a state-of-the-art review

Heart rate variability (HRV) analysis provides an assessment of cardiac vagal tone and consequently global cardiac health as well as systemic condition. In systemic diseases such as cancer and during treatments that affect the whole body, like chemotherapy, the vagus nerve activity is low and deregulated. Some studies focus on using HRV to predict mortality in oncology. However, in cancer patients, systemic alterations substantially increase artifacts during HRV measurement, especially atrial ectopic beats. Moreover, HRV may be altered by various factors (duration and time of measurement, breathing, drugs, and other confounding factors) that alter each metric in different ways. The Standard Deviation of all Normal to Normal intervals (SDNN) is the most commonly used metric to evaluate HRV in oncology, but it does not appear to be specific to the cardiac vagal tone. Thus, cardiac vagal activity diagnosis and vital prognosis of cancer patients can be biased. Our review presents the main HRV metrics that can be currently used in oncology studies and their links with vagus nerve and cancer. We present the influence of external factors and the required duration and time of measurement. Considering all these parameters, this review proposes seven key points for an assessment of HRV and cardiac vagal tone in patients with cancer.

Extrahepatic Manifestations in Alcoholic Liver Disease

Though liver is the most commonly affected organ in patients with chronic and excessive intake of alcohol, no organ is immune to toxic effects of alcohol and patients with alcohol-related liver disease (ALD) can suffer from a wide list of extrahepatic manifestations involving gastrointestinal tract, central and peripheral nervous systems, cardio vascular system, musculo-skeletal system, disruption of nutritional status, endocrinological abnormalities, hematological abnormalities and immune dysfunction. These extrahepatic organ involvements are usually overlooked by hepatologists and physicians who are mostly focused on managing life threatening complications of ALD. As a result, there is delayed diagnosis, delay in the initiation of appropriate treatment and late referral to other specialists. Some of these manifestations are of utmost clinical importance (e.g. delirium tremans and Wernicke's encephalopathy) because an early diagnosis and treatment can lead to full recovery while delayed or no treatment can result in death. On the other hand, several extrahepatic manifestations are of prognostic significance (such as alcoholic cardiomyopathy and malignancies) in which there is an increased risk of morbidity and mortality. Hence, a clear understanding and awareness of the extrahepatic manifestations of ALD is quintessential for proper management of these patients.

ECG and Heart Rate Variability in Sleep-Related Breathing Disorders

Here we discuss the current perspectives of comprehensive heart rate variability (HRV) analysis in electrocardiogram (ECG) signals as a non-invasive and reliable measure to assess autonomic function in sleep-related breathing disorders (SDB). It is a tool of increasing interest as different facets of HRV can be implemented to screen and diagnose SDB, monitor treatment efficacy, and prognose adverse cardiovascular outcomes in patients with sleep apnea. In this context, the technical aspects, pathophysiological features, and clinical applications of HRV are discussed to explore its usefulness in better understanding SDB.

Effects of ECG Data Length on Heart Rate Variability among Young Healthy Adults

The relationship between the robustness of HRV derived by linear and nonlinear methods to the required minimum data lengths has yet to be well understood. The normal electrocardiography (ECG) data of 14 healthy volunteers were applied to 34 HRV measures using various data lengths, and compared with the most prolonged (2000 R peaks or 750 s) by using the Mann-Whitney U test, to determine the 0.05 level of significance. We found that SDNN, RMSSD, pNN50, normalized LF, the ratio of LF and HF, and SD1 of the Poincaré plot could be adequately computed by small data size (60-100 R peaks). In addition, parameters of RQA did not show any significant differences among 60 and 750 s. However, longer data length (1000 R peaks) is recommended to calculate most other measures. The DFA and Lyapunov exponent might require an even longer data length to show robust results. Conclusions: Our work suggests the optimal minimum data sizes for different HRV measures which can potentially improve the efficiency and save the time and effort for both patients and medical care providers.

Randomized controlled three-arm study of NADA acupuncture for alcohol addiction

INTRODUCTION

Alcohol addiction compromises cardiovascular health, possibly due to impaired control of the heart and vasculature by the autonomic nervous system. We aimed to assess the effects of National Acupuncture Detoxification Association (NADA) acupuncture on cardiovascular autonomic functions, psychiatric comorbidities and abstinence in patients addicted to alcohol.

MATERIAL AND METHODS

A randomized sham controlled three-arm study was undertaken in 72 patients (nine females, aged 43.7 ± 9.2 years, mean ± SD) undergoing in-patient rehabilitation for alcohol addiction. Patients were randomly allocated (1:1:1) to receive twenty 30-minute NADA or sham acupuncture sessions within six weeks or no intervention. They were evaluated for craving, depression, anxiety and autonomic control of the heart (heart rate variability, HRV), vasculature (laser Doppler flowmetry) and sweat glands (sympathetic skin response). Testing was performed at baseline, immediately post intervention (sham intervention or control period, respectively) and another four weeks later. Abstinence was assessed one year after study completion.

RESULTS

Patients in the NADA arm displayed increased HRV immediately post-intervention compared to baseline (SDNN: 72.8 ms ± 34.2 ms vs. 57.9 ms ± 31.2 ms, p = 0.001). This increase was sustained four weeks later (66.2 ms ± 32.4 ms, p = 0.015). HRV remained unaltered following sham or no acupuncture (p = n.s.). Autonomic function of vasculature and sweat glands, psychiatric comorbidities and one-year abstinence did not differ between study arms.

CONCLUSIONS

NADA acupuncture may improve autonomic cardiac function. However, this improvement appears not to translate into alleviation of psychiatric comorbidities or sustained abstinence.

Evoked K-complexes and altered interaction between the central and autonomic nervous systems during sleep in alcohol use disorder

There is evidence for impairment in both central nervous system (CNS) and autonomic nervous system (ANS) function with prolonged alcohol use. While these impairments persist into abstinence, partial recovery of function has been demonstrated in both systems during sleep. To investigate potential ANS dysfunction associated with cortical CNS responses (impairment in CNS-ANS coupling), we assessed phasic heart rate (HR) fluctuation associated with tones that did and those that did not elicit a K-complex (KC) during stable N2 non-rapid eye movement (NREM) sleep in a group of 16 recently abstinent alcohol use disorder (AUD) patients (41.6 ± 8.5 years) and a group of 13 sex- and age-matched control participants (46.6 ± 9.3 years). Electroencephalogram (EEG) and electrocardiogram (ECG) data were recorded throughout the night. Alcohol consumption questionnaires were also administered to the AUD patients. AUD patients had elevated HR compared to controls at baseline prior to tone presentation. The HR fluctuation associated with KCs elicited by tone presentation was significantly smaller in amplitude, and tended to be delayed in time, in the AUD group compared with the control group, and the subsequent deceleration was also smaller in AUD patients. In both groups, the increase in HR was larger and occurred earlier when KCs were produced than when they were not, and there was no difference in the magnitude of the KC effect between groups. Phasic HR changes associated with KCs elicited by tones are impaired in AUD participants, reflecting ANS dysfunction possibly caused by an alteration of cardiac vagal trafficking. However, only the timing of the HR response was found to relate to estimated lifetime alcohol consumption in AUD. The clinical meaning and implications of these novel findings need to be determined.

Heart rate variability as a potential biomarker for alcohol use disorders: A systematic review and meta-analysis

BACKGROUND

Alcohol use disorders (AUDs) have been found to be associated with elevated cardiovascular risk. The autonomic nervous system is considered to play a role in this association. Heart rate variability (HRV) has been employed to measure parasympathetic activity in AUDs patients in some studies; however, the results are not consistent, and the adopted HRV indices vary across studies. A meta-analysis should be helpful for clarifying this topic.

METHODS

We gathered studies about measuring HRV in AUDs patients and healthy participants from databases. HRV was analyzed in several ways: parasympathetic function in hierarchical order (main analysis), total variability, and specific parasympathetic indices. Specific parasympathetic indices were further separated into high-frequency power (HF) and root mean square of the successive differences (RMSSD). For comparing the above values in patients with AUDs and in healthy individuals, we adopted the random effects model to calculate the standardized mean difference.

RESULTS

Of the 144 screened studies, 15 were included in the quantitative analysis. In the comparison of parasympathetic function in hierarchical order, HRV in AUDs patients was significantly lower than in healthy individuals (Hedges'g = -0.4301, 95% CI [-0.7601 to -0.1000], p=0.0106, I² = 83.8%). Regarding total variability and RMSSD, AUDs patients also had significantly lower values than healthy controls. However, the differences of specific parasympathetic indices and HF were not significantly different.

CONCLUSION

Our results support the view that AUDs patients have reduced parasympathetic activity. Total variability and RMSSD are suitable indices for presenting reduced HRV in patients with AUDs.

Alcohol-induced autonomic dysfunction: a systematic review

Purpose

Autonomic dysfunction is a known consequence of chronic and excessive alcohol consumption. The aim of this systematic review was to characterise this phenomenon, describe the frequency at which it occurs and to explore the best management strategies.

Methods

A systematic, computer-based search was conducted using the PubMed database. All studies identified by the search were evaluated independently by at least three authors. For inclusion, studies had to report human subjects consuming ethanol in excess. Case reports and non-original studies were excluded from this review.

Results

A total of 55 studies were included in this review. According to cardiovascular reflex tests, 16–73% of chronic alcohol abusers suffer from autonomic dysfunction. The most commonly occurring symptom is erectile dysfunction, whilst other features such as postural dizziness are rare. The most important risk factor for this condition is total lifetime dose of ethanol, although there is mixed evidence supporting the role of other risk factors. The only management strategy currently explored in the literature is abstinence, which appears to lead to significant improvement in autonomic investigations.

Conclusion

Current literature includes studies of highly heterogeneous populations, consuming differing volumes of alcohol over variable periods of time and utilising a number of different autonomic test batteries and criteria to diagnose autonomic dysfunction. Therefore, further research using homogeneous methods for measuring autonomic dysfunction in the field is needed. Despite this limitation, our review demonstrated that autonomic dysfunction is very common among alcohol abusers.

Effect of gender-related depression on heart rate variability during an autonomic nervous test

Patients with depression have lower heart rate variability (HRV) compared with controls. However, studies have indicated HRV difference between male and female controls. The gender effect might be interactive with the depression effect on the HRV, resulting in a low accuracy of recognising the patients with depression from the controls. Our study explores the effect of gender-related depression on HRV. Four ANS tests including resting, deep breathing, Valsalva, and orthostatic test are employed as stimuli. HRV were collected from 182 subjects comprising 91 depressive patients (33 females/58 males) and 91 controls (33 females/58 males) in the four tests. Time and frequency domains and nonlinear parameters are employed to quantify HRV. Two-way ANOVA is applied to evaluate the effect of gender-related depression. Most HRV parameters of the patients significantly differ from those of the controls, but some parameters indicate different depression effect between the males and females in the deep breathing and Valsalva test. Some HRV parameters illustrate significant difference between the male and female controls. Therefore, the effect of depression on HRV of each gender should be investigated.

Heart rate variability in alcohol use: A review

BACKGROUND

Prior studies have shown that resting heart rate variability (HRV) is reduced in those with alcohol use disorders (AUD). However, HRV following an acute stressful stimulus (reactive HRV), and the relationship between resting or reactive HRV and drinking, craving and relapse in AUD have received less attention.

METHODS

Studies using HRV in relationship to acute or chronic alcohol consumption were included in this review. Manuscripts that related to alcohol in the context of cardiovascular disease were excluded.

RESULTS

Thirty-three articles were included and findings are presented in healthy social drinkers, moderate/heavy drinkers without AUD and individuals with AUD. Results on resting and reactive HRV were presented separately. Acute alcohol reduced resting HRV in healthy subjects but healthy controls had higher resting HRV then AUD subjects and moderate/heavy drinkers (in some studies). Resting HRV improved in AUD subjects only after at least 4 months of abstinence. AUD subjects had higher reactive HRV scores when compared to controls. In AUD subjects increased reactivity was related to more craving, faster relapse and more negative mood. Reactive HRV showed slower improvement with abstinence in AUD subjects.

CONCLUSIONS

Chronic, heavy alcohol has a negative effect on the autonomic nervous system and may be a sensitive biomarker of craving and relapse.

Effects of Tibetan Music on Neuroendocrine and Autonomic Functions in Patients Waiting for Surgery: A Randomized, Controlled Study

Background

The aim of this study was to investigate the effects of listening to Tibetan music on anxiety and endocrine, autonomic, cognitive responses in patients waiting for urologic surgery.

Methods

Sixty patients waiting for surgery were enrolled to the study. They were randomized in music (M) and control (C) groups. The M group listened to a low-frequency Tibetan music for 30 min (T₀-T₃₀) through headphones, and the C group wore headphones with no sound. The State Trait Anxiety Inventory Questionnaire (STAI) Y-1 was administered at T₀ and T₃₀. Normalized low (LFnu) and high frequencies (HFnu) of heart rate variability, LF/HF ratio, and galvanic skin response (GRS) data were analyzed at T₀, T₁₀, T₂₀, T₃₀, and T₃₅. The salivary α-amylase (sAA) samples were collected at T₀, T₃₅, and T₄₅.

Results

In the M group, the STAI Y-1 score decreased at T₃₀ versus baseline (p < 0.001), sAA levels decreased at T₃₅ versus T₀(p=0.004), and GSR remained unchanged. In the C group, the STAI Y-1 score remained unchanged, sAA level increased at T₃₅ versus T₀(p < 0.001), and GSR slightly increased at T₃₅ versus baseline (p=0.359). LFnu was lower, and HFnu was significantly higher (T₁₀-T₃₀) in M versus C group. Mean LF/HF ratio slightly reduced in the M group.

Conclusions

Our results suggest that preoperative listening to relaxing Tibetan music might be a useful strategy to manage preoperative anxiety.

Heart Rate Variability (HRV) Analysis: A Methodology for Organizational Neuroscience

Recently, the application of neuroscience methods and findings to the study of organizational phenomena has gained significant interest and converged in the emerging field of organizational neuroscience. Yet, this body of research has principally focused on the brain, often overlooking fuller analysis of the activities of the human nervous system and associated methods available to assess them. In this article, we aim to narrow this gap by reviewing heart rate variability (HRV) analysis, which is that set of methods assessing beat-to-beat changes in the heart rhythm over time, used to draw inference on the outflow of the autonomic nervous system (ANS). In addition to anatomo-physiological and detailed methodological considerations, we discuss related theoretical, ethical, and practical implications. Overall, we argue that this methodology offers the opportunity not only to inform on a wealth of constructs relevant for management inquiries but also to advance the overarching organizational neuroscience research agenda and its ecological validity.

The role of autonomic dysfunction in cirrhotic patients before and after liver transplantation. Review of the literature

In patients affected by hepatic cirrhosis, autonomic dysfunction is a common finding; usually it is asymptomatic but it may correlate with increased mortality and morbidity before, during and after liver transplant, due to hemodynamic instability in the course of stressful events like sepsis, gastrointestinal bleeding and reperfusion after transplantation surgery. Hyperdynamic circulation and hepatic dysfunction seem to play a role in the pathogenesis of autonomic dysfunction, even if pathophysiological mechanisms are not completely known. We present a revision of previous literature about prevalence, pathophysiological mechanisms, clinical features, and mortality and morbidity of autonomic dysfunction secondary to hepatic cirrhosis.

The Association Between Moderate Drinking and Heart Rate Variability in Healthy Community-Dwelling Older Women

The relationships among moderate alcohol use, autonomic tone, and arrhythmogenesis in older adults have not been adequately studied. Knowledge about these relationships is of increasing importance in light of population aging and recent epidemiological findings that associate moderate alcohol use with decreased rates of coronary artery disease. The purpose of this study was to assess the association between moderate drinking and autonomic tone in older women. Fifty-two Caucasian female participants (age 69 ± 5.2) were enrolled in the study. Autonomic tone was estimated by time-domain and frequency-domain measures of heart rate variability. Multivariate analysis revealed that alcohol consumption rate in the sample accounted for approximately one third of the 24-h variability in the SDNN and the SDANN, measures of variability cycle lengths of 24-h and more than 5-min, respectively. Significant contributions of alcohol consumption rate to the shorter-term time-domain measures rMSSD and ASDNN, all frequency-domain measures, and HR were not confirmed. However, repeated measures ANOVA revealed that, between the hours of 0000 and 0600, women who drank approximately 0.5 to 3 standard drinks per day had significantly lower [log] HF and [log] LF power compared to abstainers and a tendency toward sympathetic predominance during the evening and nighttime hours. The authors discuss the implications of these findings.

Adolescent's respiratory sinus arrhythmia is associated with smoking rate five years later

INTRODUCTION

Vulnerability factors like respiratory sinus arrhythmia (RSA) may help identify adolescents at risk for nicotine dependence. We examined if resting RSA and the acute effects of smoking on RSA was associated with cigarette smoking five years later among adolescents at high risk for smoking escalation and nicotine dependence.

METHODS

Sixty-nine adolescents participated in a baseline laboratory session- RSA was collected before and after smoking a single cigarette ad libitum. Participants were then followed for five years.

RESULTS

Lower pre-smoke resting RSA was related to higher past month smoking rate five years later, even after controlling for baseline smoking rate and other relevant covariates including gender, race/ethnicity, age of initiated use, and frequency of exercise at baseline (p=0.018). Exploratory analyses suggested resting RSA is an independent predictor of increased cigarette rate beyond other baseline predictors.

CONCLUSIONS

Low resting RSA may be a vulnerability factor, helping to identify adolescents at risk for cigarette escalation.

Cold Face Test-Induced Increases in Heart Rate Variability Are Abolished by Engagement in a Social Cognition Task

Abstract. The vagus nerve is a major constituent in the bidirectional relationship between the heart and the prefrontal cortex. This study investigated the role of the vagus in social cognition using the cold face test (facial cooling) to stimulate the vagus nerve and increase prefrontal inhibitory control. Heart Rate Variability (HRV) was measured to index parasympathetic outflow while social cognition ability was tested using the Reading the Mind in the Eyes Test (RMET). Healthy males (n = 25) completed the RMET under two conditions: with and without facial cooling. Results indicated that although facial cooling increased HRV at rest, there was no improvement in the RMET during the facial cooling condition. Interestingly, completing the RMET with facial cooling abolished this increase in HRV, suggesting interference along the vagal reflex arc. These results are consistent with the involvement of a common cortico-subcortical circuit in autonomic and cognitive processes, important for emotion recognition.

A pilot study of brief heart rate variability biofeedback to reduce craving in young adult men receiving inpatient treatment for substance use disorders

The present pilot study investigated the implementation feasibility, and efficacy for reducing alcohol and drug craving, of a brief, 3-session heart rate variability biofeedback (HRV BFB) intervention added to a traditional 28-day substance abuse disorder inpatient treatment program. Forty-eight young adult men received either treatment as usual (TAU) plus three sessions of HRV BFB training over 3 weeks, or TAU only. Participants receiving HRV BFB training were instructed to practice daily using a hand-held HRV BFB device. HRV BFB training was well tolerated by participants and supported by treatment staff. Men receiving TAU + HRV BFB demonstrated a greater, medium effect size reduction in alcohol and drug craving compared to those receiving TAU only, although this difference did not reach statistical significance. In addition, an interaction effect was observed in analyses that accounted for baseline craving levels, wherein heart rate variability (HRV) levels at treatment entry were predictive of changes in craving in the TAU group only. Low baseline levels of HRV were associated with increases in craving, whereas higher baseline HRV levels were associated with greater decreases in craving from start to end of treatment. In the TAU + HRV BFB group, however, there was no such association. That is, HRV BFB appeared to dissociate individual differences in baseline HRV levels from changes in craving. Given that alcohol and drug craving often precipitates relapse, HRV BFB merits further study as an adjunct treatment to ameliorate craving experienced by persons with substance use disorders.

Poor autonomic nervous system functioning during sleep in recently detoxified alcohol-dependent men and women

BACKGROUND

Alcoholism is considered an important risk factor for cardiovascular (CV) disease. Autonomic nervous system (ANS) function is a major indicator of CV health. Sleep is a suitable model to investigate ANS activity free from wake-related confounders. We investigated nighttime ANS functioning, and the relation between ANS activity and severity of alcohol dependence in chronic alcoholism.

METHODS

Fourteen recently abstaining alcoholics (age: 42.0 ± 9.0 years, 7 women) and 16 age- and sex-matched controls (age: 45.2 ± 9.1 years, 8 women) underwent a night of standard clinical polysomnography, including electrocardiographic recording. Time- and frequency-domain spectral analysis of heart rate variability (HRV) was performed across hours of the night and during artifact-free epochs of stable sleep and wakefulness (presleep wakefulness, rapid-eye-movement [REM], and non-REM sleep).

RESULTS

Alcoholics had a poorer subjective and objective sleep quality compared to controls. Across the night, alcoholic men and women had elevated heart rate, reduced total HRV, that is, lower standard deviation of normal-to-normal interbeat intervals, and reduced high frequency (HF) activity (assessed by the HF power and by the square root of the mean squared of successive heart period differences). This ANS pattern was most apparent at the beginning of the night. None of the ANS measures was associated with lifetime alcohol consumption or duration of alcohol dependence.

CONCLUSIONS

Our results show that ANS functioning is disrupted during the night, even in undisturbed sleep periods, indicating poor CV functioning in recently detoxified alcohol-dependent men and women.

Autonomic dysfunction in essential hypertension: A systematic review

Introduction

Greater sympathetic drive has been established in the early stages of essential hypertension, suggesting that neurohormonal dysregulation may be key to its aetiology and progression. The aims of this review are to discuss evidence of the role of autonomic dysfunction in essential hypertension and proposed mechanisms, and also some applications of this knowledge to current management strategies of essential hypertension.

Methods

A computer search was performed using the PUBMED database for peer reviewed original articles comparing autonomic function tested via heart rate variability (HRV), muscle sympathetic nerve activity (MSNA) or plasma noradrenaline levels in normotensive (mean blood pressure (BP) of ≤140/90 mmHg or ≤135/85 mmHg if measured via home BP measurements) and hypertensive groups (mean resting BP of ≥140/90 mmHg (or ≥135/85 mmHg if measured via home BP measurements). Subjects were excluded with secondary causes of hypertension or autonomic dysfunction.

Results

A total of 17 studies were included for discussion. The main findings of this study include that of reduced baroreflex sensitivity, believed to be secondary to increased arterial stiffness, is hypothesised to be implicated in the pathogenesis of essential hypertension. Also, angiotensin converting enzyme inhibitors were not as effective on markers of autonomic control of blood pressure when compared with alternative anti-hypertensive drugs.

Conclusions

Consistent research is needed to establish the effectiveness of pharmacotherapies at each of stage of hypertension, and on markers of autonomic dysfunction. Consistent study designs will enable more accurate accumulation of data across multiple studies, and appropriate application of such data into clinical practice.

Habitual alcohol consumption is associated with lower cardiovascular stress responses--a novel explanation for the known cardiovascular benefits of alcohol?

In contrast to heavy alcohol consumption, which is harmful, light to moderate drinking has been linked to reduced cardiovascular morbidity and mortality. Effects on lipid status or clotting do not fully explain these benefits. Exaggerated cardiovascular responses to mental stress are detrimental to cardiovascular health. We hypothesized that habitual alcohol consumption might reduce these responses, with potential benefits. Advanced magnetic resonance techniques were used to accurately measure cardiovascular responses to an acute mental stressor (Montreal Imaging Stress Task) in 88 healthy adults (∼1:1 male:female). Salivary cortisol and task performance measures were used to assess endocrine and cognitive responses. Habitual alcohol consumption and confounding factors were assessed by questionnaire. Alcohol consumption was inversely related to responses of heart rate (HR) (r = -0.31, p = 0.01), cardiac output (CO) (r = -0.32, p = 0.01), vascular resistance (r = 0.25, p = 0.04) and mean blood pressure (r = -0.31, p = 0.01) provoked by stress, but not to stroke volume (SV), or arterial compliance changes. However, high alcohol consumers had greater cortisol stress responses, compared to moderate consumers (3.5 versus 0.7 nmol/L, p = 0.04). Cognitive measures did not differ. Findings were not explained by variations in age, sex, social class, ethnicity, physical activity, adrenocortical activity, adiposity, smoking, menstrual phase and chronic stress. Habitual alcohol consumption is associated with reduced cardiac responsiveness during mental stress, which has been linked to lower risk of hypertension and vascular disease. Consistent with established evidence, our findings suggest a mechanism by which moderate alcohol consumption might reduce cardiovascular disease, but not high consumption, where effects such as greater cortisol stress responses may negate any benefits.

Heart rate variability during sleep in detoxified alcohol-dependent males: A comparison with healthy controls

CONTEXT

Alcohol dependence can lead to autonomic neuropathy resulting in increased cardiac morbidity and mortality. This has previously been evaluated using heart-rate variability.

AIMS

We compared sleep heart-rate variability of alcohol-dependent patients with that of healthy controls in this study.

SETTINGS AND DESIGN

This study was conducted at NIMHANS, Bangalore. A case control study design was adopted.

MATERIALS AND METHODS

Sleep heart-rate variability of 20 male alcohol-dependent inpatients was recorded on the 5(th) day after detoxification. Sleep heart-rate variability was also recorded in 18 age- and gender-matched healthy controls.

STATISTICAL ANALYSIS

The groups were compared using t-test for continuous variables and Chi-squared test for discrete variables.

RESULTS

Both time and frequency domain measures were significantly lower in the patients as compared to the controls, indicating decreased HRV in alcohol-dependent individuals.

CONCLUSIONS

Decreased HRV in alcohol dependence indicates potential autonomic neuropathy.

Different associations of alcohol cue reactivity with negative alcohol expectancies in mandated and inpatient samples of young adults

Alcohol cue reactivity, operationalized as a classically conditioned response to an alcohol related stimulus, can be assessed by changes in physiological functions such as heart rate variability (HRV), which reflect real time regulation of emotional and cognitive processes. Although ample evidence links drinking histories to cue reactivity, it is unclear whether in-the-moment cue reactivity becomes coupled to a set of consolidated beliefs about the effects of alcohol (i.e., expectancies) and whether treatment helps dissociate the relation of positive versus negative expectancies to cue reactivity. This study examined the relationship between reactivity to alcohol picture cues and alcohol expectancies in two groups of emerging adults: an inpatient sample with alcohol use disorders (n=28) and a college student sample who previously were mandated to a brief intervention for violating university policies about alcohol use in residence halls (n=43). Sequential regression analysis was conducted using several HRV indices and self-report arousal ratings as cue reactivity measures. Results indicated that the relationship between cue reactivity and negative alcohol outcome expectancies differed for the two groups. Greater cue reactivity, assessed using HRV indices, was associated with more negative expectancies in the inpatient sample but with less negative expectancies in the mandated student sample, while an opposite trend was found for subjective arousal. The present findings highlight the importance of characterizing cue reactivity through multi-dimensional assessment modalities that include physiological markers such as HRV.

Alcohol-dependence syndrome: Postural challenge on heart rate variability

BACKGROUND

Cardiac autonomic involvement in Alcohol-Dependence Syndrome (ADS) patients has been demonstrated using conventional autonomic tests. Resting heart rate variability (HRV) without normalization has also been reported.

AIMS

To evaluate cardiac autonomic changes with postural challenge using HRV in ADS and controls while controlling for confounding factors.

SETTINGS AND DESIGN

Cross-sectional study involving 27 male subjects with ADS and age-matched healthy controls.

MATERIALS AND METHODS

Clinical assessments included Schedules for Clinical Assessment in Neuropsychiatry and Severity of Alcohol Dependence Questionnaire. Spectral measures of HRV while lying and with active standing were assessed.

RESULTS

There was an attenuated response in delta high-frequency (P=0.06) and delta low-frequency (P=0.04) power to standing in ADS subjects compared with controls.

CONCLUSION

Patients with ADS appear to have attenuated cardiac vagal and sympathetic responses to standing. HRV with postural challenge may help earlier recognition of autonomic dysfunction in ADS.

Association between anxiety disorders and heart rate variability in The Netherlands Study of Depression and Anxiety (NESDA)

OBJECTIVE

To determine whether patients with different types of anxiety disorder (panic disorder, social phobia, generalized anxiety disorder) have higher heart rate and lower heart rate variability compared with healthy controls in a sample that was sufficiently powered to examine the confounding effects of lifestyle and antidepressants.

METHODS

The standard deviation of the normal-to-normal intervals (SDNN), heart rate (HR), and respiratory sinus arrhythmia (RSA) were measured in 2059 subjects (mean age = 41.7 years, 66.8% female) participating in The Netherlands Study of Depression and Anxiety (NESDA). Based on the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition (DSM-IV) and Composite International Diagnostic Interview (CIDI), NESDA participants were classified as healthy controls (n = 616), subjects with an anxiety diagnosis earlier in life (n = 420), and subjects with current anxiety diagnosis (n = 1059).

RESULTS

Current anxious subjects had a significantly lower SDNN and RSA compared with controls. RSA was also significantly lower in remitted anxious subjects compared with controls. These associations were similar across the three different types of anxiety disorders. Adjustment for lifestyle had little impact. However, additional adjustment for antidepressant use reduced all significant associations between anxiety and HRV to nonsignificant. Anxious subjects who used a tricyclic antidepressant, a selective serotonin reuptake inhibitor, or another antidepressant showed significantly lower mean SDNN and RSA compared with controls (effect sizes = 0.20-0.80 for SDNN and 0.42-0.79 for RSA). Nonmedicated anxious subjects did not differ from controls in mean SDNN and RSA.

CONCLUSION

This study shows that anxiety disorders are associated with significantly lower HR variability, but the association seems to be driven by the effects of antidepressants.

Effects of chronic moderate alcohol consumption and novel environment on heart rate variability in primates (Macaca fascicularis)

RATIONALE

The effects of chronic moderate alcohol consumption on cardiac function are not understood. Acute stress may affect cardiac function by shifting autonomic cardiac regulation in favor of the sympathetic nervous system. Although alcohol consumption often increases at times of stress, the interactive effects of stress and chronic moderate alcohol consumption on cardiac regulation have not been studied.

OBJECTIVES AND METHODS

The objective was to assess the effects of long-term (1-2 years) moderate (a two-drink/day equivalent, 5 days/week) alcohol consumption on heart rate (HR) variability under normal and acutely stressful conditions in small stable groups of ovariectomized adult cynomolgus monkeys (Macaca fascicularis). Monkeys were trained to voluntarily drink their daily alcohol dose (<30 min), and blood levels were determined an hour later. The animals were acutely stressed by removal from the home cage to a novel environment for 30 min. HR in freely moving subjects was recorded via telemetry in the home cage and the novel environment.

RESULTS

Acute stress increased HR, decreased HR variability, and decreased the high frequency component of the power spectrum suggesting reduced parasympathetic cardiac modulation. Chronic moderate alcohol consumption decreased HR variability and the low frequency components of the power spectrum. When stressed, monkeys with a history of chronic moderate alcohol consumption had higher HRs than the controls.

CONCLUSIONS

HR dynamics in monkeys rapidly respond to acute stress. Chronic moderate alcohol consumption may be deleterious to cardiac function. HR response to stress may be exaggerated when accompanied by a history of chronic moderate alcohol consumption.

Heart rate variability: a review

Heart rate variability (HRV) is a reliable reflection of the many physiological factors modulating the normal rhythm of the heart. In fact, they provide a powerful means of observing the interplay between the sympathetic and parasympathetic nervous systems. It shows that the structure generating the signal is not only simply linear, but also involves nonlinear contributions. Heart rate (HR) is a nonstationary signal; its variation may contain indicators of current disease, or warnings about impending cardiac diseases. The indicators may be present at all times or may occur at random-during certain intervals of the day. It is strenuous and time consuming to study and pinpoint abnormalities in voluminous data collected over several hours. Hence, HR variation analysis (instantaneous HR against time axis) has become a popular noninvasive tool for assessing the activities of the autonomic nervous system. Computer based analytical tools for in-depth study of data over daylong intervals can be very useful in diagnostics. Therefore, the HRV signal parameters, extracted and analyzed using computers, are highly useful in diagnostics. In this paper, we have discussed the various applications of HRV and different linear, frequency domain, wavelet domain, nonlinear techniques used for the analysis of the HRV.

Heart rate variability: a review

Heart rate variability (HRV) is a reliable reflection of the many physiological factors modulating the normal rhythm of the heart. In fact, they provide a powerful means of observing the interplay between the sympathetic and parasympathetic nervous systems. It shows that the structure generating the signal is not only simply linear, but also involves nonlinear contributions. Heart rate (HR) is a nonstationary signal; its variation may contain indicators of current disease, or warnings about impending cardiac diseases. The indicators may be present at all times or may occur at random-during certain intervals of the day. It is strenuous and time consuming to study and pinpoint abnormalities in voluminous data collected over several hours. Hence, HR variation analysis (instantaneous HR against time axis) has become a popular noninvasive tool for assessing the activities of the autonomic nervous system. Computer based analytical tools for in-depth study of data over daylong intervals can be very useful in diagnostics. Therefore, the HRV signal parameters, extracted and analyzed using computers, are highly useful in diagnostics. In this paper, we have discussed the various applications of HRV and different linear, frequency domain, wavelet domain, nonlinear techniques used for the analysis of the HRV.

Heart rate variability: a review

Heart rate variability (HRV) is a reliable reflection of the many physiological factors modulating the normal rhythm of the heart. In fact, they provide a powerful means of observing the interplay between the sympathetic and parasympathetic nervous systems. It shows that the structure generating the signal is not only simply linear, but also involves nonlinear contributions. Heart rate (HR) is a nonstationary signal; its variation may contain indicators of current disease, or warnings about impending cardiac diseases. The indicators may be present at all times or may occur at random-during certain intervals of the day. It is strenuous and time consuming to study and pinpoint abnormalities in voluminous data collected over several hours. Hence, HR variation analysis (instantaneous HR against time axis) has become a popular noninvasive tool for assessing the activities of the autonomic nervous system. Computer based analytical tools for in-depth study of data over daylong intervals can be very useful in diagnostics. Therefore, the HRV signal parameters, extracted and analyzed using computers, are highly useful in diagnostics. In this paper, we have discussed the various applications of HRV and different linear, frequency domain, wavelet domain, nonlinear techniques used for the analysis of the HRV.

Heart rate variability: measurement and clinical utility

Electrocardiographic RR intervals fluctuate cyclically, modulated by ventilation, baroreflexes, and other genetic and environmental factors that are mediated through the autonomic nervous system. Short term electrocardiographic recordings (5 to 15 minutes), made under controlled conditions, e.g., lying supine or standing or tilted upright can elucidate physiologic, pharmacologic, or pathologic changes in autonomic nervous system function. Long-term, usually 24-hour recordings, can be used to assess autonomic nervous responses during normal daily activities in health, disease, and in response to therapeutic interventions, e.g., exercise or drugs. RR interval variability is useful for assessing risk of cardiovascular death or arrhythmic events, especially when combined with other tests, e.g., left ventricular ejection fraction or ventricular arrhythmias.

Wine drinking is associated with increased heart rate variability in women with coronary heart disease

OBJECTIVE

To test the hypothesis that alcohol consumption is positively related to heart rate variability (HRV) in women with coronary heart disease (CHD) and therefore that cardiac autonomic activity is potentially implicated in the mediation of the favourable effects of moderate drinking.

DESIGN, SETTINGS, AND PATIENTS

Cross sectional study of female patients who survived hospitalisation for acute myocardial infarction or underwent a revascularisation procedure, percutaneous transluminal coronary angioplasty, or coronary artery bypass grafting.

MAIN OUTCOME MEASURES

Ambulatory 24 hour ECG was recorded during normal activities. The mean of the standard deviations of all normal to normal intervals for all five minute segments of the entire recording (SDNNI) and the following frequency domain parameters were assessed: total power, high frequency power, low frequency power, and very low frequency power. A standardised questionnaire evaluated self reported consumption of individual alcoholic beverage types: beer, wine, and spirits. Other clinical characteristics, such as age, body mass index, smoking habits, history of diabetes mellitus, menopausal status, educational status, and treatment, were also assessed.

RESULTS

Wine intake was associated with increased HRV in both time and frequency domains independently of other clinical covariates (for example, ln SDNNI was 3.89 among wine drinkers v 3.59 among wine non-drinkers in the multivariate model; p = 0.014). In contrast, consumption of beer and spirits and the total amount of alcohol consumed did not relate significantly to any of the HRV parameters.

CONCLUSION

Intake of wine, but not of spirits or beer, is positively and independently associated with HRV in women with CHD. These results may contribute to the understanding of the complex relation between alcohol consumption and CHD.

Cardiovascular autonomic function in healthy adolescents

OBJECTIVE

The purpose of this study was to determine effects of age, sex, race, body mass index, and Tanner's stage on short-term evoked cardiovascular autonomic tests (ie, Valsalva ratio and change in heart rate with deep breathing) and 24-hour heart rate variability (HRV) in a sample of healthy adolescents, as well as to identify normative indices of both short-term evoked and 24-hour HRV in this age group.

DESIGN

A descriptive, correlational design was used.

SETTING

Study took place in a university hospital in a health science center located in the mid-South.

SUBJECTS

Participants included 75 healthy adolescents: mean age was 15.0 +/- 1.6 years, 14 were African American, 61 were white, 49 were girls, and 26 were boys.

OUTCOME MEASURES

Study measures included the Valsalva ratio, change in heart rate with deep breathing, and 24-hour HRV with power spectral analysis with Holter monitoring.

RESULTS

Major significant findings included lower values of 24-hour HRV measures for girls and African American adolescents (P <.05). Indices for normal ranges of both the short-term evoked and 24-hour HRV measures were computed with 95% confidence intervals.

CONCLUSIONS

Few published studies address cardiac autonomic function, including 24-hour HRV, in adolescents. Most studies reporting actual normative control values of HRV for youth typically have not addressed sex or racial differences. Our study included the largest number of adolescents to date in the reported literature and demonstrated the importance of considering sex and race variation in interpreting test results. The availability of state-of-the-art technology for obtaining HRV data allows for the early identification of subclinical cardiac autonomic changes in youth who have predispositions for cardiac complications, such as those with diabetes, congenital heart disease, or obesity.

A theoretical model of the role of brain stem nuclei in alcohol-mediated arrhythmogenesis in older adults

Uncertainty about the mechanism of alcohol-mediated arrhythmogenesis and the effect of alcohol use on arrhythmic risk among older adults is an increasing concern in light of population aging and recent reports that moderate alcohol consumption may protect older adults against coronary artery disease. In this review, a theoretical model of the role of brain stem nuclei in alcohol-mediated arrhythmogenesis in older adults is developed. The model is based on the hypothesis that the effects of alcohol on central autonomic pathways of cardiac control may alter the threshold for alcohol-mediated arrhythmogenesis among older adults. Findings from multiple lines of research including cellular, electrophysiological, epidemiological, experimental, and clinical studies in human, animal, and in vitro models were synthesized in developing the model. Suggestions for future research on the topic of alcohol-mediated arrhythmogenesis in older adults are offered.

Assessing the suitability of cross-sectional and longitudinal cardiac rhythm tests with regard to identifying effects of occupational chronic lead exposure

The aim of this study was to examine whether signs of neurotoxic influence on the autonomic nervous system, after lengthy occupational lead exposure, could be revealed by appropriate cardiac rhythm analysis. A total of 109 male lead-exposed workers and 27 controls were examined in a cross-sectional study. In addition, 17 lead-exposed participants were investigated a second time in a follow-up study 4 years later. Heart rate variability was assessed in rest, strain, and recovery phases. In the cross-sectional study, lead-exposed persons showed a delayed restoration of cardiac rhythm parameters to the initial vegetative state after the strain phase. This effect significantly increased over a period of 4 more years of exposure in the 17 workers participating in the follow-up study. We found vagal depression caused by long-term lead exposure within the current threshold limit value range, which can be interpreted as an adverse effect.

The time-course of electrocardiographic interbeat interval dynamics in alcoholic subjects after short-term abstinence

Alcohol dependence has been correlated with decreases in heart rate variability. However, the time course of recovery of heart rate variability after cessation of alcohol consumption is unknown. We used electrocardiogram (ECG) data serially obtained from a population of detoxifying alcoholic subjects to determine the Hurst exponent of the ECG interbeat interval time series. Higher values of the Hurst exponent are associated with decreased heart rate variability when H< or =0.5. We tested a series of response-surface models relating the Hurst exponent (H) thus obtained to the following independent variables: the time interval T (days since last use of alcohol), A (age in years at time of admission), and gender. The best-fit model was: H(T)=(KA+H(m)T+H(f)T)/(1+T), F=5.2, P(F)</=0.01. Model parameters were: K=0.008+/-0.002 (mean+/-SEM); asymptotic H-values for males and females: H(m)=0.24+/-0.02 and H(f)=0.16+/-0.03, respectively, significantly different at P< or =0.05. Age was the strongest predictor of initial H-values in this alcoholic population sample.

Deficits of respiratory-cardiac coupling in heavy drinkers

1. Physiological evidence of chronic alcohol abuse prior to the onset of clinical signs of alcohol dependence is difficult to obtain The purpose of this study was to search for possible non-invasive indicators for chronic alcohol consumption yielding information in addition to conventional biological markers. 2. The authors investigated the relationship between respiratory-cardiac coupling and blood alcohol concentration (BAC) in male subjects who lost their driver's license from drunk driving. 3. We found that subjects who had a high BAC level (0.16-0.31% at the time of offense) show altered respiratory sinus arrhythmia (RSA) and, in particular, an altered heart-rate response to auditory stimulation and compared them to a control group of social drinkers. Normal subjects showed a pronounced acoustic heart-rate response, i.e., particularly during expiration there was a difference between the interbeat-interval (IBI) traces with and without auditory stimulation. Subjects who had lost their driver's license from drunk driving had an overall severely reduced heart-rate response, that was even absent particularly in the subgroup having high BAC values (0.21-0.31%). The authors also found some evidence that in the latter subgroup IBI, RSA, and acoustic heart-rate responses partially recover after a six-month period of abstinence. 4. Specific parameters of the acoustic heart-rate response are changed in our group of alcohol abusers presumably, due to impairment of vagal function. These parameters may therefore be useful to serve as a non-invasive measure of alcohol abuse.

Changes in clinical measures of autonomic nervous system function related to cancer chemotherapy-induced nausea

Individual cancer patients differ in their nausea/vomiting response to chemotherapy. It is not known why patients receiving the same chemotherapy have different severity of side effects. Several lines of research implicate the autonomic nervous system (ANS) in the development of chemotherapy-induced nausea. We examined the association between autonomic reactivity and the level of nausea experienced following chemotherapy in 20 patients with ovarian cancer treated with cisplatin or carboplatin who received the same antiemetic. We applied eight common non-invasive clinical tests of autonomic function prior to inpatient chemotherapy treatment, 2 h after treatment and again 24 h following treatment. Two hours after chemotherapy and before any nausea was reported by the patients, the nine patients who subsequently experienced high levels of nausea had a greater overall percentage of abnormal clinical ANS tests than the 11 patients who subsequently developed low levels of nausea (P < 0.01). Twenty-four hours after treatment, the overall number of abnormal autonomic tests remained non-significantly higher than at the pretreatment baseline for the high nausea group. Demographic and clinical characteristics were not related to chemotherapy-induced nausea in this sample. Autonomic reactivity appears to be related to the development of nausea following chemotherapy. Further investigation of ANS involvement in chemotherapy-induced nausea could increase understanding of nausea etiology and potentially lead to the prediction of susceptible patients.

Alcohol, cardiac arrhythmias and sudden death

Studies in experimental animals have shown varying and apparently opposite effects of alcohol on cardiac rhythm and conduction. Given acutely to non-alcoholic animals, ethanol may even have anti-arrhythmic properties whereas chronic administration clearly increases the animals' susceptibility to cardiac arrhythmias. Chronic heavy alcohol use has been incriminated in the genesis of cardiac arrhythmias in humans. The evidence has come from clinical observations, retrospective case-control studies, controlled studies of consecutive admissions for arrhythmias, and prospective epidemiological investigations. Furthermore, electrophysiological studies have shown that acute alcohol administration facilitates the induction of tachyarrhythmias in selected heavy drinkers. The role of alcohol appears particularly conspicuous in idiopathic atrial fibrillation. Occasionally, ventricular tachyarrhythmias have also been provoked by alcohol intake. Several lines of evidence suggest that heavy drinking increases the risk of sudden cardiac death with fatal arrhythmia as the most likely mechanism. According to epidemiological studies this effect appears most prominent in middle-aged men and is only partly explained by confounding traits such as smoking and social class. The basic arrhythmogenic effects of alcohol are still insufficiently delineated. Subclinical heart muscle injury from chronic heavy use may be instrumental in producing patchy delays in conduction. The hyperadrenergic state of drinking and withdrawal may also contribute, as may electrolyte abnormalities, impaired vagal heart rate control, repolarization abnormalities with prolonged QT intervals and worsening of myocardial ischaemia or sleep apnoea. Most of what we know about alcohol and arrhythmias relates to heavy drinking. The effect of social drinking on clinical arrhythmias in non-alcoholic cardiac patients needs to be addressed further.

Alcoholism, peripheral neuropathy (PNP) and cardiovascular autonomic neuropathy (CAN)

In contrast to diabetic autonomic neuropathy, cardiovascular autonomic neuropathy (CAN) in long-term alcoholics has been studied rarely. Using both standardized bedside tests and computer-assisted analysis of heart rate variability (HRV), we prospectively compared autonomic neurocardial function between 35 strictly selected, detoxified alcoholics (DSM-III-R), and 80 well matched healthy controls. Evidence for a potential CAN was found in 25.7% of all the alcoholics studied and in 41% of those with clinically manifest PNP (n=22). Overall, our results demonstrated a significant association between the presence of a CAN and peripheral neuropathy (PNP) amongst chronic alcoholics (chi-square test P<0.05); there was no evidence of a CAN in any of the alcoholics without a clinically manifest PNP. The CAN was characterized by a dissociated appearance of parasympathetic and sympathetic disorders. Our findings provide reason to suspect that the total lifetime dose of alcohol and the duration of alcohol dependence are the most important factors contributing to the pathogenesis of both PNP and sympathetic dysfunction. As is the case with diabetics, computer-assisted measurements of HRV including spectral analysis appear to be far superior to conventional bedside tests for detecting evidence of cardiovagal dysfunction in long-term alcoholics.

Impairment of metabolic hepatic nerve action by chronic but not acute ethanol intoxication studied in isolated perfused rat liver

BACKGROUND/AIMS

Liver carbohydrate metabolism and blood flow are regulated by hepatic nerves and hormones such as glucagon, insulin or catecholamines. Acute and chronic application of alcohol are known to depress the function of central and peripheral nerves. The extent of inhibition of the autonomic nervous system is not well characterized; thus, the possible impairment of hepatic nerve function by acute and chronic application of ethanol was investigated.

METHODS

Rat livers were perfused simultaneously via both the portal vein and hepatic artery. Hepatic nerves were stimulated electrically for 2 min (20 Hz, 20 V, 2 ms). As a control, noradrenaline (1 microM) was infused into the portal vein for 2 minutes.

RESULTS

During acute application of ethanol in portal concentrations of 50, 150 and 300 mM, which elevated basal glucose release, stimulation of hepatic nerves as well as portal noradrenaline infusion caused the same increase in glucose output and decrease in portal and arterial flow as in controls. Following chronic application of ethanol by feeding rats the Lieber-DeCarli liquid diet containing 5% (v/v) ethanol for 4 and 6 weeks, only nerve stimulation caused a significantly reduced enhancement of glucose output (50%, p < 0.025), whereas portal noradrenaline was as effective as in controls. Noradrenaline overflow was significantly reduced following nerve stimulation.

CONCLUSION

The decrease in nerve stimulation-dependent glucose output and noradrenaline overflow in chronically ethanol fed rats indicates an impaired function of hepatic nerves.

Autonomic cardiac abnormalities in alcohol-dependent patients admitted to a psychiatric department

Standardized heart rate analyses were performed in 60 drug-free patients with alcohol dependence, who were admitted consecutively to a psychiatric department, and in 60 healthy normal matched subjects. The procedure included time and frequency derived measurements of heart rate variability (HRV). The investigations were carried out 3 weeks after admission and treatment on a closed ward to avoid autonomic hyperexcitability during withdrawal or relapse. The patients showed a significantly increased heart rate (p < 0.05), a significant reduction in the coefficient of variation while resting (p < 0.01) and a significant decrease of the high frequency power of spectral analysis (p < 0.01) compared with the normal subjects. Cardiovascular autonomic dysfunction was found in 12 of the patients, but in only one of the normal subjects (p < 0.01). The results indicated moderate parasympathetic (vagal) alteration in alcohol-dependent patients treated in a psychiatric department. This may have implications for psychotherapeutic or psychopharmacological treatment strategies and prognosis in such patients with alcohol dependence.

Autonomic measures associated with chemotherapy-related nausea: techniques and issues

Advances in antiemetic therapy for cancer patients have been hindered by a lack of understanding of the physiological mechanisms associated with nausea and their corresponding measurement techniques. Here we review conceptual and methodological issues involved in developing an autonomic frame of reference for nausea and outline two strategies for assessing autonomic function. A primarily research-oriented strategy uses heart rate, blood volume pulse, pallor, and skin temperature to assess autonomic activity and reactivity over 24 hr. Peak values of these measures relative to time of emesis, heart rate spectral analyses of autonomic activity, and analyses of the standard deviation of successive differences of beat-to-beat intervals were all associated with subsequent nausea. A primarily clinically oriented strategy assesses normal and abnormal results on eight common bedside clinical tests of autonomic function. The total number of abnormal tests was associated with subsequent nausea. A better understanding of chemotherapy side effect mechanisms is likely to result in less polypharmacy and more effective individualized treatment for cancer patients.

Autonomic neurotoxicity of alcohol assessed by heart rate variability

Measurement of heart rate variability (CVR-R) provides a promising approach for evaluation of the autonomic nervous function. Specifically, high- and low-frequency component coefficients of variation of the CVR-R (C-CVHF and C-CVLF), computed from component spectral powers by autoregressive spectral and component analyses, are inferred to reflect parasympathetic and sympathetic activities, respectively. To assess the acute and chronic effects of alcohol on parasympathetic and sympathetic activities, ECGs in the supine posture were obtained in 11 male healthy volunteers, and in 23 male patients with severe alcoholic dependency together with the same number of age-matched healthy men. Significant changes in the CVR-R and heart rate were found 1 h after ethanol intake in the volunteers; also, the 1-h alteration in heart rate after intake was inversely correlated with that in the C-CVHF. The CVR-R, C-CVHF and C-CVLF were significantly depressed in the alcoholics compared to the matched controls. In the alcoholics, the age-adjusted correlation coefficients between not only the CVR-R but also C-CVHF and heart rate were negatively significant. These data suggest that acute and habitual intake of alcohol affects cardiac autonomic functions including sympathetic and parasympathetic activities; and, increase of heart rate in relation to alcohol, at least in alcoholics, seems to occur through reducing the parasympathetic activity.

Short-term heart rate variability and factors modifying the risk of coronary artery disease in a population sample

Heart rate (HR) variability is impaired in chronic coronary artery disease (CAD), but the mechanism is not fully resolved. This study was aimed at assessing whether HR variability is influenced by the risk factors of CAD. Of a random sample of 120 subjects born in 1954, 88 (41 men and 47 women) could be included in the analyses. No subject had clinical heart disease. The subjects' physical activity, alcohol consumption and smoking were quantified by 2-month diary follow-up. Serum lipids and insulin were measured. The tests of HR variability included power spectral analysis and calculation of the root-mean-square difference of RR intervals at rest under controlled respiration. HR variability indexes were asymmetrically distributed and strongly HR-dependent, and therefore, all statistical tests were performed on log-transformed data adjusted to the population mean HR. Multiple regression analyses showed independent inverse relations between the root-mean-square RR difference and low-density lipoprotein (LDL) cholesterol (beta = -0.22; p = 0.008), and between the total RR-interval power and LDL cholesterol (beta = -0.25; p = 0.007), as well as smoking (beta = -0.19; p = 0.035). In women, alcohol use influenced the RR-interval root-mean-square difference (beta = 0.31; p = 0.015), total power (beta = 0.33; p = 0.017) and high-frequency power (beta = 0.26; p = 0.056). It is concluded that short-term HR variability is related inversely to LDL cholesterol and smoking in the population, and directly to alcohol use in women.(ABSTRACT TRUNCATED AT 250 WORDS)