Exeter Head Impacts, Brain Injury and Trauma (ExHIBIT) Research Group, Department of Public Health and Sport Sciences, University of Exeter, Exeter, UK.
J Sleep Res. 2024 Oct;33(5):e14145. doi: 10.1111/jsr.14145. Epub 2024 Jan 16.
Habitual poor sleep is associated with cerebrovascular disease. Acute sleep deprivation alters the ability to match brain blood flow to metabolism (neurovascular coupling [NVC]) but it is not known how partial sleep restriction affects NVC. When rested, caffeine disrupts NVC, but its effects in the sleep-restricted state are unknown. The purpose of this study was therefore to investigate the effects of partial sleep restriction and subsequent caffeine ingestion on NVC. A total of 17 adults (mean [standard deviation] age 27 [5] years, nine females) completed three separate overnight conditions with morning supplementation: habitual sleep plus placebo (Norm_Pl), habitual sleep plus caffeine (Norm_Caf), and partial (50% habitual sleep) restriction plus caffeine (PSR_Caf). NVC responses were quantified as blood velocity through the posterior (PCAv) and middle (MCAv) cerebral arteries using transcranial Doppler ultrasound during a visual search task and cognitive function tests, respectively. NVC was assessed the evening before and twice the morning after each sleep condition-before and 1-h after caffeine ingestion. NVC responses as a percentage increase in PCAv and MCAv from resting baseline were not different at any timepoint, across all conditions (p > 0.053). MCAv at baseline, and PCAv at baseline, peak, and total area under the curve were lower 1-h after caffeine in both Norm_Caf and PSR_Caf as compared to Norm_Pl (p < 0.05), with no difference between Norm_Caf and PSR_Caf (p > 0.14). In conclusion, NVC was unaltered after 50% sleep loss, and caffeine did not modify the magnitude of the response in the rested or sleep-deprived state. Future research should explore how habitual poor sleep affects cerebrovascular function.
习惯性睡眠不佳与脑血管疾病有关。急性睡眠剥夺会改变大脑血液流动与代谢相匹配的能力(神经血管耦合[NVC]),但目前尚不清楚部分睡眠限制如何影响 NVC。休息时,咖啡因会破坏 NVC,但在睡眠受限状态下的影响尚不清楚。因此,本研究旨在探讨部分睡眠限制和随后摄入咖啡因对 NVC 的影响。共有 17 名成年人(平均[标准差]年龄 27[5]岁,9 名女性)在三个单独的夜间条件下完成了包含清晨补充剂的实验:习惯性睡眠加安慰剂(Norm_Pl)、习惯性睡眠加咖啡因(Norm_Caf)和部分(50%习惯性睡眠)限制加咖啡因(PSR_Caf)。使用经颅多普勒超声在视觉搜索任务中分别量化大脑后(PCAv)和中(MCAv)动脉的血流速度,作为 NVC 反应。在每个睡眠条件前一晚和清晨两次评估 NVC-在咖啡因摄入前和摄入后 1 小时。在任何时间点,在所有条件下,NVC 反应(PCAv 和 MCAv 从休息基线的百分比增加)均无差异(p>0.053)。与 Norm_Pl 相比,在 Norm_Caf 和 PSR_Caf 中,咖啡因摄入后 1 小时,基线 MCAv 和基线、峰值和总曲线下面积的 PCAv 较低(p<0.05),但 Norm_Caf 和 PSR_Caf 之间无差异(p>0.14)。总之,50%的睡眠损失后 NVC 没有改变,而咖啡因在休息或睡眠剥夺状态下都没有改变反应的幅度。未来的研究应该探讨习惯性睡眠不佳如何影响脑血管功能。