The association between neuroticism and heart rate variability is not fully explained by cardiovascular disease and depression

Neuroticism is associated with cardiovascular disease, autonomic reactivity, and depression. Here we address the extent to which neuroticism accounts for the excess heart disease risk associated with depression and test whether cardiac autonomic tone plays a role as mediator. Subjects were derived from a nationally representative sample (n = 1,255: mean age 54.5, SD = 11.5). Higher neuroticism was associated with reduced heart rate variability equally under rest and stress. The baseline structural equation model revealed significant paths from neuroticism to heart rate variability, cardiovascular disease and depression, and between depression and cardiovascular disease, controlling for age, sex, height, weight, and BMI. Dropping both the neuroticism to heart rate variability, and neuroticism to heart disease paths significantly reduced the model fit (p < .001 in each case). We conclude that neuroticism has independent associations with both autonomic reactivity and cardiovascular disease, over and above its associations with depression and other related variables

Towards an objective quantitative assessment of daily functioning in migraine: a feasibility study

Migraine is a chronic disabling disorder, with migraine episodes significantly reducing quality of life and leading to impaired functioning (physically, socially, emotionally) bath at home and at work. We explored whether ambulatory accelerometry can be used as an objective method to quantify the behavioral aspects of migraine-related disability. Four body mounted uni-axial piezo-resistive accelerometers were used to quantify the time spent in different body postures (lying, sitting, standing), physical activities (walking, cycling) and a general index of body motility during eight migraine attacks and subsequent recovery periods of six patients in their habitual environment. The migraine attacks and recovery periods could be monitored after about 1 h, which was the time required for the investigator to travel to the patient and for the sensors to be attached. Ln order to quantify the influence of a migraine episode on daily activities, we also performed measurements during a headache-free baseline period of the same patients. Overall, the procedures functioned well, indicating that ambulatory accelerometry measurements before, during and after a migraine attack are feasible to perform. Furthermore, our quantitative data revealed that migraine always influenced behavior by reducing overall body motility and that, dependent upon the severity of the attack, the effectiveness of acute treatment and the time of day, the time spent in various body positions, dynamic activities, and the number of postural transitions were affected. This feasibility study showed that ambulatory accelerometry can provide the objective behavioral effect parameters for the evaluation of migraine and its treatment on daily functioning in the habitual environment of migraine patients. (C) 2000 International Association for the Study of Pain. Published by Elsevier Science B.V. All rights reserved

EFFECTS OF LORAZEPAM ON CARDIAC VAGAL TONE DURING REST AND MENTAL STRESS - ASSESSMENT BY MEANS OF SPECTRAL-ANALYSIS

Dose-dependent effects of intravenously administered lorazepam on haemodynamic fluctuations were studied by means of spectral analysis, in order to elucidate sympathetic and parasympathetic components in cardiovascular control during situations of rest and mental stress after benzodiazepine administration. In a double-blind randomized cross-over study, nine male volunteers participated in two sessions: a placebo and lorazepam session. During these sessions, the subjects repeatedly performed a 10-min version of the Stroop Color Word Test (CWT), with 10 min of rest between the CWTs. Lorazepam was administered before each rest period in increasing doses of 0.0, 0.06, 0.13, 0.25 and 0.5 mg (total cumulative dose: 0.94 mg). During the placebo session the subjects received five placebo injections. For five of the nine subjects the lorazepam session was their first session. Heat rate (HR), blood pressure (BP) and respiration were recorded continuously. Power spectra were calculated per 2.5-min periods for HR, systolic (SBP) and diastolic BP (DBP). Spectral density was assessed for three frequency bands: low (LFB: 0.02-0.06 Hz), mid (MFB: 0.07-0.14 Hz) and high (HFB: 0.15-0.40 Hz). During the consecutive periods of rest, lorazepam induced a dose-dependent decrease in HR, and a dose-dependent increase in LFB, MFB and HFB power of HR, but lorazepam had no effect on BP. The effects were significant after 0.44 mg lorazepam for HR and HFB power, and after 0.94 mg lorazepam for the HR fluctuations in the LFB and MFB. Lorazepam did not influence the cardiovascular responses to the CWT. Our data underline that benzodiazepines can exert a specific influence on parasympathetic activity: lorazepam induced dose-dependent increases in cardiac vagal tone, resulting in decreased HR and increased HR variability, but only during periods of rest. The increase in vagal tone observed after low doses of lorazepam was not related to diminished sympathetic activity, altered respiration, or increased sedation

Accelerometry in cardiovascular psychophysiology: New perspectives for ambulatory research

Interpretation of real-life stress-related cardiovascular responses requires knowledge of both the type and the amount of daily activities, since changes in body posture and locomotor activity have a profound effect on ambulatory recorded cardiovascular signals. Simultaneous recording of cardiovascular and locomotor activity may therefore facilitate the interpretation of prolonged cardiovascular measurements in clinical and experimental research. We evaluated accelerometry as a method to quantify both static (lying, sitting, standing) and dynamic activities in a study that was designed to assess the sedative effects of benzodiazepines on cardiovascular functioning in relation to normal daily activities. Our validation study showed that accelerometry by means of body-mounted sensors forms a valid method to quantify aspects of normal daily activities. Furthermore, our quantification of body postures and physical activity, in relation to heart rate, proved to be sufficiently sensitive to differentiate the placebo from the pharmacological conditions. Ambulatory monitoring of combined cardiovascular and accelerometer signals therefore proved to be a promising method for psychophysiological research

Accelerometry in cardiovascular psychophysiology:New perspectives for ambulatory research

Interpretation of real-life stress-related cardiovascular responses requires knowledge of both the type and the amount of daily activities, since changes in body posture and locomotor activity have a profound effect on ambulatory recorded cardiovascular signals. Simultaneous recording of cardiovascular and locomotor activity may therefore facilitate the interpretation of prolonged cardiovascular measurements in clinical and experimental research. We evaluated accelerometry as a method to quantify both static (lying, sitting, standing) and dynamic activities in a study that was designed to assess the sedative effects of benzodiazepines on cardiovascular functioning in relation to normal daily activities. Our validation study showed that accelerometry by means of body-mounted sensors forms a valid method to quantify aspects of normal daily activities. Furthermore, our quantification of body postures and physical activity, in relation to heart rate, proved to be sufficiently sensitive to differentiate the placebo from the pharmacological conditions. Ambulatory monitoring of combined cardiovascular and accelerometer signals therefore proved to be a promising method for psychophysiological research

Accelerometry in cardiovascular psychophysiology:New perspectives for ambulatory research

Interpretation of real-life stress-related cardiovascular responses requires knowledge of both the type and the amount of daily activities, since changes in body posture and locomotor activity have a profound effect on ambulatory recorded cardiovascular signals. Simultaneous recording of cardiovascular and locomotor activity may therefore facilitate the interpretation of prolonged cardiovascular measurements in clinical and experimental research. We evaluated accelerometry as a method to quantify both static (lying, sitting, standing) and dynamic activities in a study that was designed to assess the sedative effects of benzodiazepines on cardiovascular functioning in relation to normal daily activities. Our validation study showed that accelerometry by means of body-mounted sensors forms a valid method to quantify aspects of normal daily activities. Furthermore, our quantification of body postures and physical activity, in relation to heart rate, proved to be sufficiently sensitive to differentiate the placebo from the pharmacological conditions. Ambulatory monitoring of combined cardiovascular and accelerometer signals therefore proved to be a promising method for psychophysiological research

Differences in potential biomarkers of delirium between acutely ill medical and elective cardiac surgery patients

Angelique Egberts,1 Robert J Osse,2 Durk Fekkes,2,3 Joke HM Tulen,2 Tischa JM van der Cammen,1 Francesco US Mattace-Raso1 1Section of Geriatric Medicine, Department of Internal Medicine, Erasmus MC University Medical Center, Rotterdam, the Netherlands; 2Department of Psychiatry, Erasmus MC University Medical Center, Rotterdam, the Netherlands; 3Department of Clinical Chemistry, Erasmus MC University Medical Center, Rotterdam, the Netherlands Background/aims: The pathophysiology of delirium is poorly understood. Increasing evidence suggests that different pathways might be involved in the pathophysiology depending on the population studied. The aim of the present study was to investigate potential differences in mean plasma levels of neopterin, amino acids, amino acid ratios and homovanillic acid between two groups of patients with delirium.Methods: Data from acutely ill medical patients aged 65 years and older, and patients aged 70 years and older undergoing elective cardiac surgery, were used. Differences in biomarker levels between the groups were investigated using univariate ANOVA with adjustments for age, sex, comorbidities, C-reactive protein (CRP) and the estimated glomerular filtration rate (eGFR), where appropriate. Linear regression analysis was used to identify potential determinants of the investigated biochemical markers.Results: Eighty patients with delirium were included (23 acutely ill medical patients and 57 elective cardiac surgery patients). After adjustment, higher mean neopterin levels (93.1 vs 47.3 nmol/L, P=0.001) and higher phenylalanine/tyrosine ratios (1.39 vs 1.15, P=0.032) were found in acutely ill medical patients when compared to elective cardiac surgery patients. CRP levels were positively correlated with neopterin levels in acutely ill medical patients, explaining 28.4% of the variance in neopterin levels. eGFR was negatively correlated with neopterin in elective cardiac surgery patients, explaining 53.7% of the variance in neopterin levels.Conclusion: In this study, we found differences in mean neopterin levels and phenylalanine/tyrosine ratios between acutely ill medical and elective cardiac surgery patients with delirium. Moreover, our findings may suggest that in acutely ill medical patients, neopterin levels are mainly determined by inflammation/oxidative stress whereas in elective cardiac surgery patients, neopterin levels are mainly driven by renal function/fluid status. These findings suggest that the markers and pathways that might be involved in the pathophysiology of delirium may differ between specific groups of patients. Keywords: delirium, inflammation, neopterin, oxidative stress, renal functio