Heart rate–corrected QT interval in men increases during winter months

Beyerbach, Daniel; Kovacs, Richard J.; Dmitrienko, Alexei; Rebhun, Dawn M.; Zipes, Douglas P.

doi:10.1016/j.hrthm.2006.11.008

Cited by 25 publications

(17 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…It is not uncommon to observe large intersubject variability (ISV) and/or within‐subject variability in these key cardiovascular safety variables even in a well‐controlled phase I setting, making data interpretation more challenging. Diurnal variations, changes in the environment, ingestion of meals, and stress associated with study activities are known to influence some of these parameters …”

mentioning

confidence: 99%

“…Diurnal variations, changes in the environment, ingestion of meals, and stress associated with study activities are known to influence some of these parameters. 2,3 Because the study design characteristics, baseline demographics, and random unexplained variability can confound interpretation of the cardiovascular safety signal and potentially delay or halt development of otherwise effective medicines, the objective of this work was to use a model-based approach to quantitatively characterize the time-course and inherent variability in key cardiovascular measures and identify the sources of variability using data from subjects who received placebo in 65 single-dose and multiple-dose phase I trials conducted by AbbVie. These analyses were envisioned to aid physicians in understanding the range of what can be observed on placebo in terms of cardiovascular parameters in the phase I setting.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Models of Variability and Circadian Rhythm in Heart Rate, Blood Pressure, and QT Interval for Healthy Subjects Who Received Placebo in Phase I Trials

Minocha

Chiu

et al. 2019

Clinical Translational Sci

View full text Add to dashboard Cite

This work characterized the time‐course, circadian rhythm, and inherent variability in key cardiovascular variables (heart rate, corrected QT interval, and systolic and diastolic blood pressure) that are routinely collected as part of safety monitoring in phase I trials. Longitudinal data from 1,035 healthy volunteers who received placebo in 65 single‐dose and multiple‐dose phase I trials conducted by AbbVie were compiled and analyzed using nonlinear mixed‐effects modeling. An independent nonlinear mixed‐effects model was developed for each variable, and combinations of cosine functions were used to capture circadian oscillations. Gender, race, age, and body weight were significant covariates for variability in baseline measures, and the contributions of these covariates were quantitatively characterized. Based on the extensive data set analyzed, the developed models represent valuable tools to help contextualize and differentiate inherent variability that can be expected in a typical phase I setting from true drug‐related cardiovascular safety signals. In addition, these placebo models can be used to support exposure–response analyses that estimate treatment‐related effects on the evaluated cardiovascular measures.

show abstract

mentioning

confidence: 99%

mentioning

confidence: 99%

Models of Variability and Circadian Rhythm in Heart Rate, Blood Pressure, and QT Interval for Healthy Subjects Who Received Placebo in Phase I Trials

Minocha

Chiu

et al. 2019

Clinical Translational Sci

View full text Add to dashboard Cite

show abstract

“…Patients with anorexia nervosa have longer QT intervals than controls with normal body weight 37. Finally, the QTc of normal subjects has been shown to demonstrate diurnal variation (longer during sleep and during REM sleep in particular),38 39 and the QTc in otherwise healthy men is significantly longer in winter months than summer months 40…”

Section: Confoundersmentioning

confidence: 96%

QTc: how long is too long?

2009

View full text Add to dashboard Cite

Congenital long QT syndrome (LQTS) affects an estimated 1 in 2500 people and typically presents with syncope, seizures or sudden death. Whereas someone exhibiting marked prolongation of the QT interval with QTc exceeding 500 ms who was just externally defibrillated from torsades de pointes while swimming poses negligible diagnostic challenge as to the unequivocal probability of LQTS, the certainty is considerably less for the otherwise asymptomatic person who happens to host a QTc value coined “borderline” (QTc ≥440 ms). Although a normal QT interval imparts a much lower risk of life-threatening events, it does not preclude a patient from nevertheless harbouring a potentially lethal LQTS-causing genetic mutation. Indeed, genetic testing exerts significant diagnostic, prognostic and therapeutic implications. However, the 12-lead ECG remains the universal initial diagnostic test in the evaluation of LQTS and is subject to miscalculation, misinterpretation and mishandling. This review discusses the components of accurate QTc measurement and diagnosis, re-examines what is known about factors affecting QT interval measurement, and clarifies current recommendations regarding diagnosis of so-called “borderline” QT interval prolongation. The current guideline recommendations for the athlete with LQTS are also summarised.

show abstract

“…In this way, it is interesting to review some findings that explain an increase in cardiac events to cold temperatures: 1) There is 53% more cases of acute myocardial infarction reported during the winter compared with the summer 13 . In these lines, most of reports, but not all, have demonstrated a significant winter increase in cardiovascular abnormalities and cardiac death, especially in the northern hemisphere, where there are winter temperature extremes 14,15 . Quite interesting, sudden cardiac death have been also reported in regions with most comfortable winter 16,17 , 2) During the winter, increases in haemoconcentration (erythrocyte count, plasma cholesterol and plasma fibrinogen levels) have been reported, which could contribute to arterial thrombosis 18 .…”

Section: Discussionmentioning

confidence: 98%

Is cold the new hot in sudden unexpected death in epilepsy? Effect of low temperature on heart rate of rats with epilepsy

Sonoda

Colugnati

Scorza

et al. 2008

Arq. Neuro-Psiquiatr.

View full text Add to dashboard Cite

-Sudden unexpected death in epilepsy (SUDEP) is the commonest cause of seizure-related mortality in people with refractory epilepsy. Several risk factors for SUDEP are described; however, the importance of including low temperatures as risk factor for SUDEP was never explored. Based on this, the aim of this study was to evaluate the heart rate of rats with epilepsy during low temperature exposure. Our results showed that low temperature clearly increased the heart rate of rats with epilepsy. Taken together, we concluded that exposure to low temperatures could be considered important risk factors from cardiovascular abnormalities and hence sudden cardiac death in epilepsy.KEy wOrDS: epilepsy, seizure, SUDEP, low temperatures, heart. É o frio responsável por mortes inesperadas em epilepsia ? Efeito de temperaturas baixas na frequência cardíaca de ratos com epilepsia.Resumo -A morte súbita e inesperada nas epilepsias (SUDEP) é considerada a maior causa de morte em indivíduos com epilepsia refratária. Vários fatores de risco para SUDEP têm sido descritos, no entanto, a inclusão das baixas temperaturas como um possível fator de risco para SUDEP não foi verificada até o momento. Nesse sentido, o objetivo desse estudo foi verificar a freqüência cardíaca de animais com epilepsia expostos as temperaturas baixas. Nossos resultados demonstraram que as baixas temperaturas são capazes de aumentar significativamente a freqüência cardíaca de animais com epilepsia. Dessa forma, concluímos que as baixas temperaturas podem ser consideradas um importante fator de risco de possíveis alterações cardiovasculares e até mesmo morte súbita cardíaca nas epilepsias.PAlAVrAS-chAVE: epilepsia, crises epilépticas, SUDEP, baixas temperaturas, coração. The epilepsies are the most common serious neurological condition. In developed countries, the incidence of epilepsy is around 50 per 100 000 people per year, and is higher in infants and elderly people 1,2 . The most commonly reported etiological factors are tumors, head injuries, stroke, genetic inheritance and infections of the central nervous system 1,3 . In resource-poor countries, endemic infections, such as neurocysticercosis and malaria seem to be major risk factors 1 . Moreover, people with epilepsy are two-to three-fold increase to die prematurely than those without epilepsy and the most common epilepsyrelated category of death is sudden unexpected death in epilepsy (SUDEP).SUDEP is defined as sudden, unexpected, witnessed or unwitnessed, nontraumatic and nondrowning deaths in patients with epilepsy, with or without evidence of a seizure and excluding documented status epilepticus (SE), in which post mortem examination does not reveal a toxicological or anatomical cause of death 4 . Information concerning risk factors for SUDEP is conflicting, but potential risk factors include: age, early onset of epilepsy, duration of epilepsy, uncontrolled seizures, seizure frequency, seizure type and antiepileptic drugs number 5 . The exact pathophysiological causes of SUDEP are unknown, b...

show abstract

Heart rate–corrected QT interval in men increases during winter months

Cited by 25 publications

References 36 publications

Models of Variability and Circadian Rhythm in Heart Rate, Blood Pressure, and QT Interval for Healthy Subjects Who Received Placebo in Phase I Trials

Models of Variability and Circadian Rhythm in Heart Rate, Blood Pressure, and QT Interval for Healthy Subjects Who Received Placebo in Phase I Trials

QTc: how long is too long?

Is cold the new hot in sudden unexpected death in epilepsy? Effect of low temperature on heart rate of rats with epilepsy

Contact Info

Product

Resources

About