Circadian Variation in Cardiac Autonomic Activity: Reactivity Measurements to Different Types of Stressors

Abstract

The role of endogenous circadian rhythmicity in autonomic cardiac reactivity to different stressors was investigated. A constant routine protocol was used with repeated exposure to a dual task and a cold pressor test. The 29 subjects were randomly divided into two groups in order to manipulate prior wakefulness. Group 1 started at 09:00 h immediately after a monitored sleep period, whereas group 2 started 12 h later. Measures of interbeat intervals (IBI), respiratory sinus arrythmia (RSA, a measure of parasympathetic activity), pre-ejection period (PEP, a measure of sympathetic activity), as well as core body temperature (CBT) were recorded continuously. Multilevel regression analyses (across-subjects) revealed significant (mainly 24 h) sinusoidal circadian variation in the response to both stressors for IBI and RSA, but not for PEP. Individual 24 + 12 h cosine fits demonstrated a relatively large interindividual variation of the phases of the IBI and RSA rhythms, as compared to that of the CBT rhythm. Sinusoidal by group interactions were found for IBI and PEP, but not for RSA. These findings were interpreted as an indication for endogenous circadian and exogenous parasympathetic (vagal) modulation of cardiac reactivity, while sympathetic reactivity is relatively unaffected by the endogenous circadian drive and mainly influenced by exogenous factors.

Effects of variation in posture and respiration on RSA and pre‐ejection period

“…Higher afterload will elongate preejection period by prolonging the time needed to open the aortic valve, even if contractility is unchanged. The low (or even reversed) pre-ejection period reactivity found during cold stress is another instance of the impact of afterload on pre-ejection period, where changes in pre-ejection period fail to detect the strong increase in sympathetic nerve activity ( van Doornen, Snieder, & Boomsma, 1998;van Eekelen, Houtveen, & Kerkhof, 2004;Frey & Kenney, 1979;Montoya, Brody, Beck, Veit, & Rau, 1997). In contrast to the strong posture effect, changing the respiratory frequency had virtually no effect on the pre-ejection period.…”

Considerations in the assessment of heart rate variability in biobehavioral research

“…Cardioactive medication use, including some antidepressant classes (e.g., tricyclics; Kemp et al, 2010), some antipsychotic classes (e.g., clozapine; Cohen et al, 2001), benzodiazepines (Agelink et al, 2002), and antihypertensives (Schroeder et al, 2003) are also usually accounted for, although this may be somewhat difficult in practice when testing patient populations. Other factors that are usually accounted for include the time of day (Massin et al, 2000; van Eekelen et al, 2004), levels of habitual alcohol use (Quintana et al, 2013a,b), physical activity levels (Britton et al, 2007; Soares-Miranda et al, 2014), and age (O’Brien et al, 1986). Digestion of food and water are less commonly accounted for in HRV research, but both provoke a coordinated autonomic response.…”

Moon effects women’s asleep cardiac autonomic function

“…Cardiac automaticity, heart rate and rhythm are controlled by the autonomic nervous system (Heart rate variability 1996), and the autonomic nervous system, especially CAF, follows a circadian pattern (Linsell et al 1985;Hermida et al 2001), sympathetic activity being influenced mainly by exogenous factors (van Eekelen et al 2004). However, no data in the scientific literature show a lunar influence on the autonomic nervous system.…”