77 research outputs found
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Using Wearable Skin Temperature Data to Advance Tracking and Characterization of the Menstrual Cycle in a Real-World Setting.
The menstrual cycle is a loop involving the interplay of different organs and hormones, with the capacity to impact numerous physiological processes, including body temperature and heart rate, which in turn display menstrual rhythms. The advent of wearable devices that can continuously track physiological data opens the possibility of using these prolonged time series of skin temperature data to noninvasively detect the temperature variations that occur in ovulatory menstrual cycles. Here, we show that the menstrual skin temperature variation is better represented by a model of oscillation, the cosinor, than by a biphasic square wave model. We describe how applying a cosinor model to a menstrual cycle of distal skin temperature data can be used to assess whether the data oscillate or not, and in cases of oscillation, rhythm metrics for the cycle, including mesor, amplitude, and acrophase, can be obtained. We apply the method to wearable temperature data collected at a minute resolution each day from 120 female individuals over a menstrual cycle to illustrate how the method can be used to derive and present menstrual cycle characteristics, which can be used in other analyses examining indicators of female health. The cosinor method, frequently used in circadian rhythms studies, can be employed in research to facilitate the assessment of menstrual cycle effects on physiological parameters, and in clinical settings to use the characteristics of the menstrual cycles as health markers or to facilitate menstrual chronotherapy
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Identifying high school risk factors that forecast heavy drinking onset in understudied young adults
Heavy alcohol drinking is a major, preventable problem that adversely impacts the physical and mental health of US young adults. Studies seeking drinking risk factors typically focus on young adults who enrolled in 4-year residential college programs (4YCP) even though most high school graduates join the workforce, military, or community colleges. We examined 106 of these understudied young adults (USYA) and 453 4YCPs from the National Consortium on Alcohol and NeuroDevelopment in Adolescence (NCANDA) by longitudinally following their drinking patterns for 8 years from adolescence to young adulthood. All participants were no-to-low drinkers during high school. Whereas 4YCP individuals were more likely to initiate heavy drinking during college years, USYA participants did so later. Using mental health metrics recorded during high school, machine learning forecasted individual-level risk for initiating heavy drinking after leaving high school. The risk factors differed between demographically matched USYA and 4YCP individuals and between sexes. Predictors for USYA drinkers were sexual abuse, physical abuse for girls, and extraversion for boys, whereas 4YCP drinkers were predicted by the ability to recognize facial emotion and, for boys, greater openness. Thus, alcohol prevention programs need to give special consideration to those joining the workforce, military, or community colleges, who make up the majority of this age group
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Multi-dimensional predictors of first drinking initiation and regular drinking onset in adolescence: A prospective longitudinal study
Early adolescent drinking onset is linked to myriad negative consequences. Using the National Consortium on Alcohol and NeuroDevelopment in Adolescence (NCANDA) baseline to year 8 data, this study (1) leveraged best subsets selection and Cox Proportional Hazards regressions to identify the most robust predictors of adolescent first and regular drinking onset, and (2) examined the clinical utility of drinking onset in forecasting later binge drinking and withdrawal effects. Baseline predictors included youth psychodevelopmental characteristics, cognition, brain structure, family, peer, and neighborhood domains. Participants (N=538) were alcohol-naïve at baseline. The strongest predictors of first and regular drinking onset were positive alcohol expectancies (Hazard Ratios [HRs]=1.67-1.87), easy home alcohol access (HRs=1.62-1.67), more parental solicitation (e.g., inquiring about activities; HRs=1.72-1.76), and less parental control and knowledge (HRs=.72-.73). Robust linear regressions showed earlier first and regular drinking onset predicted earlier transition into binge and regular binge drinking (βs=0.57-0.95). Zero-inflated Poisson regressions revealed that delayed first and regular drinking increased the likelihood (Incidence Rate Ratios [IRR]=1.62 and IRR=1.29, respectively) of never experiencing withdrawal. Findings identified behavioral and environmental factors predicting temporal paths to youthful drinking, dissociated first from regular drinking initiation, and revealed adverse sequelae of younger drinking initiation, supporting efforts to delay drinking onset
Cardiovascular Hyperarousal and Primary Insomnia
Previous researches has shown autonomic, neuroendocrine, neuroimmunological, elecrophysiological and neuroimaging evidence of increased levels of arousal during wakefulness and sleep in primary insomnia. However, few studies have focused on cardiovascular activity across sleep stages and there are even fewer that have studied cardiovascular activity during the process of falling asleep.
The aim of the present study is to analyze cardiovascular activity during sleep in primary insomniacs compared to good sleepers. We also aim to detect differences in cardiovascular activity and cognitive performance between insomniacs and good sleepers. This will be done by employing Impedance Cardiography and heart rate variability (HRV) analysis. The task employed, Stop Signal Task, assesses motor inhibition processes and was administered in two sessions, before and after a night of polysomnographic recording.
Performance results showed prolonged Stop Signal Delay (SSD) in the morning in both groups and slower Stop Signal Reaction Time (SSRT) in insomniacs compared with good sleepers, while no effects were observed for performance accuracy. The myocardial contractility, in insomniacs, was higher (elevated heart rate and reduced left ventricular ejection time) in the evening task session and during wake compared to sleep. Pre-ejection period, an index inversely related to sympathetic beta-adrenergic activity, was lower in insomniacs overall the night and task sessions in agreement with the hypothesized sympathetic hyperactivity underlied the disorder. In addition, HRV indexes showed an increased parasympathetic involvement (elevated high frequency) in wake, but only in insomniacs.
These findings suggest that, in insomniacs, a greater parasympathetic activation is required to fall asleep; possibly to contrast the sympathetic hyperactivation reflected in other variables. In addition, these findings suggest a deficit of motor inhibition control in insomnia, matched with high levels of cardiovascular arousal.
These results support the etiological hypothesis of physiological hyperarousal underlying primary insomnia. Furthermore, elevated contractility indexes suggest an association between insomnia and increased risk for cardiovascular diseases.Dalla letteratura emerge come l’insonnia sia associata ad una condizione di iperattivazione generalizzata. Ciononostante solamente pochi studi si sono focalizzati sull’attività cardiovascolare nel sonno degli insonni ed in particolar modo rimane poco studiato l’addormento, ritenuto fondamentale nella comprensione del disturbo.
Lo scopo dello studio è di analizzare l’attività cardiovascolare durante il sonno nell’insonnia primaria utilizzando la Cardiografia ad Impedenza e misure derivate dall’analisi della variabilità della frequenza cardiaca. Inoltre ci si propone di analizzare la prestazione cognitiva e la reattività cardiovascolare ad un compito che coinvolge l’inibizione motoria, in un gruppo di insonni confrontati con buoni dormitori.
I risultati dello studio mostrano, negli insonni, un rallentamento nei tempi di risposta ai segnali di stop (SSRT), mentre l’accuratezza non sembra differire tra insonni e controlli.
A livello fisiologico, gli insonni, alla sera e nel confronto tra veglia e sonno, mostravano un elevata contrattilità miocardica (maggiore frequenza cardiaca e minore tempo di eiezione ventricolare sinistra). Il periodo pre-eiettivo, un indice inversamente relato all’attività simpatica beta-adrenergica, era inferiore negli insonni in tutte le condizioni sperimentali. In aggiunta, gli indici derivati dalla variabilità della frequenza cardiaca hanno evidenziato negli insonni un incremento del coinvolgimento parasimpatico in veglia.
Questi risultati suggeriscono come negli insonni sia necessaria un importante influenza vagale per permettere l’addormentamento, possibilmente per contrastare l’iperattivazione simpatica. In aggiunta, questi risultati suggeriscono un deficit nel controllo dell’inibizione motoria negli insonni che contemporaneamente esibiscono degli elevate livelli di arousal cardiovascolare durante l’esecuzione del compito.
I risultati supportano l’ipotesi eziologica di una iperattivazione psicofisiologica alla base del disturbo. Inoltre, gli elevati indici di contrattilità negli insonni, suggeriscono un associazione tra insonnia e rischio cardiovascolare
Cardiac autonomic profile during rest and working memory load in essential hypotensive women
To our knowledge, no previous study has provided reliable data supporting a different modulation of the Neurovegetative system in essential hypotension. Our purpose was to provide, in essential hypotensive women compared to normotensives, evidence of a distinct sympathetic and parasympathetic cardiac control. Cardiovascular and autonomic indexes derived by impedance cardiography (heart rate, HR; pre-ejection period, PEP), photoplethysmographic technique (blood pressure, BP) and heart rate variability analysis (high and low frequencies power, HF and LF) were continuously collected during rest and mental stress condition. Hypotensives, compared to normotensives, exhibited prolonged PEP (low sympathetic tone) and elevated HF (high vagal involvement) during rest. In addition, they showed cardiovascular (reduced increases in BP and HR) and sympathetic (lower reductions of PEP) hypo-reactivity to the task. Furthermore, a lower sympathetic reactivity in hypotensiveswas associated to a poorer task performance. Essential hypotensionwas characterized by a low sympathetic and high parasympathetic tone. In addition, a reduced sympathetic nervous system reactivity suggests the main role of the Neurovegetative system in mediating the relationship between blood pressure and cognitive performance in hypotensives
Impaired cerebral and systemic hemodynamics under cognitive load in young hypotensives: a transcranial Doppler study
Reduced sympathetic outflow and deficits in cerebral hemodynamics have been considered as possible factors mediating the impaired cognitive performance in essential hypotension. However, the relationship between systemic blood pressure (BP), cerebral blood flow and cognitive functioning is still poorly understood. The present study was aimed at clarifying the physiological processes underlying cerebral and systemic hemodynamics in young hypotensives during cognitive engagement. Doppler sonography blood flow velocities in both middle cerebral arteries were measured from 17 hypotensives and 15 normotensives during a working memory task. Impedance cardiographic and BP measures were also recorded continuously. Lower increases in systolic and diastolic BP were observed in hypotensives. However, no evidence of lower sympathetic control was found for this group, as assessed by pre-ejection period. Flow velocity in middle
cerebral arteries showed a lower increase in hypotensives throughout the task. Moreover, significant positive correlations between BP changes and blood flow velocities in middle cerebral arteries during the task were obtained for this group only, suggesting a less effective cerebral autoregulation. No difference was found between groups in task performance. Results suggest that during cognitive challenge hypotensives show impaired hemodynamic adjustments, both central and peripheral. However, such alterations do not directly affect cognitive performance, at least under moderate cognitive load
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