The Influence Of Sleep On Blood Pressure In Healthy Children

Abstract

Loss of ideal cardiovascular health can begin in childhood with the development of cardiovascular disease (CVD) risk factors occurring on a continuum. Central blood pressure (BP) values may be more reflective of CVD risk than peripheral BP but are rarely measured in children. Additionally, in adults, poor sleep quality is associated with higher BP and incidence of CVD, however these relations are not as well elucidated in children. PURPOSE: To evaluate the role of sleep duration, sleep quality, and sleep variability (SLV) on resting central and peripheral BP in apparently healthy 7-12 yr old children. METHODS: Sleep duration, total time in bed (TTIB), sleep quality (assessed by sleep efficiency (SE) and wake after sleep onset (WASO)), and SLV (assessed by sleep midpoint standard deviation (SMSD)) were recorded in 20 healthy children (10 ± 0.5 yrs, 10 boys, 10 girls) for 7 consecutive nights outside of the laboratory via wrist accelerometry. Following sleep monitoring, peripheral BP was measured and using pulse wave analysis (PWA) central BP was estimated. Central and peripheral BP were measured and averaged over 3 trials. Pearson’s r correlations were used to assess relations between sleep metrics and BP values. Independent samples t-tests were used to determine group (low vs. high SE) differences. RESULTS: Sleep duration averaged 7.9 ± 0.2 hrs/night, while TTIB averaged 9.6 ± 0.1 hrs/night. SE was 82 ± 2%, WASO was 89 ± 9 mins, and SMSD was 48 ± 6 mins. Sleep duration, TTIB, SE, WASO, and SMSD were not significantly associated with central or peripheral BP values. When using an 85% cutoff for SE, central and peripheral BP were not significantly different between groups. Additionally, using the same cutoff for SE, TTIB was not significantly different between groups, however sleep duration was significantly different (7.4 hrs <85% vs 8.4 hrs >85%, p < 0.001). CONCLUSION: Preliminary data suggest that children age 7-12 are not getting the recommended amount of sleep (9-11 hrs/night) despite adequate time in bed. Thus far, there seems to be no effect of shortened, poor-quality, and more variable sleep on BP in healthy children age 7-12, but further research is needed. Supported by NIH grant P20GM113125