The association between sleep duration and muscle sympathetic nerve activity

Abstract

Purpose Sleep duration is associated with risk of hypertension and cardiovascular diseases. It is thought that shorter sleep increases sympathetic activity. However, most studies are based on acute experimental sleep deprivation that have produced conflicting results. Furthermore, there are limited data available on habitual sleep duration and gold-standard measures of sympathetic activation. Hence, this study aimed to assess the association between habitual sleep duration and muscle sympathetic nerve activity. Methods Twenty-four participants aged ≥ 18 years were included in the study. Sleep was assessed using at-home 7-day/night actigraphy (ActiGraph™ GT3X-BT) and sleep questionnaires (Pittsburgh Sleep Quality Index and Epworth Sleepiness Scale). Microelectrode recordings of muscle sympathetic nerve activity were obtained from the common peroneal nerve. Participants were categorised into shorter or longer sleep duration groups using a median split of self-report and actigraphy sleep measures. Results Compared to longer sleepers, shorter sleepers averaged 99 ± 40 min and 82 ± 40 min less sleep per night as assessed by self-report and objective measures, respectively. There were no differences in age (38 ± 18 vs 39 ± 21 years), sex (5 male, 7 female vs 6 male, 6 female), or body mass index (23 ± 3 vs 22 ± 3 kg/m2) between shorter and longer sleepers. Expressed as burst frequency, muscle sympathetic nerve activity was higher in shorter versus longer sleepers for both self-report (39.4 ± 12.9 vs 28.4 ± 8.5 bursts/min, p = 0.019) and objective (37.9 ± 12.4 vs 28.1 ± 8.8 bursts/min, p = 0.036) sleep duration. Conclusions Shorter sleep duration assessed in a home setting was associated with higher muscle sympathetic nerve activity. Sympathetic overactivity may underlie the association between short sleep and hypertension.

Sleep Duration Irregularity is Associated with Elevated Blood Pressure During Submaximal Exercise in Young Adults

“…stemming from sympathetic hyperactivity [4][5][6]. However, our index of sympathetic modulations of the heart (LF/ HF ratio) was not associated with sleep duration regularity or the rise in systolic BP during exercise.…”

“… 4 Possible mechanisms that explain this phenomenon include augmented sympathetic activity and decreased baroreflex sensitivity that are reported to occur after sleep loss. 5 , 6 Thus, analyzing for sleep duration regularity may be a useful tool to capture the impact of intermittent nights of insufficient sleep on BP dysregulation.…”

Short Sleep Duration Disrupts Glucose Metabolism: Can Exercise Turn Back the Clock?

“…Also, a decrease in brain glucose utilization, concomitant with the drop in cognitive performance that occurs with total sleep deprivation could potentially contribute to the disruption of whole-body glucose utilization (81). Researchers also have consistently shown that sleep restriction increases sympathetic nervous system activity (17,24,27,82,83), which is known to regulate insulin and glucagon secretion (84).…”