0267 Feasibility of an Experimental Protocol Inducing Variable Sleep in Healthy Teens

Abstract

Introduction: Experimental sleep manipulation work in adolescents has primarily focused on the effects of differing overall sleep duration on cognitive, emotional, and physical health outcomes. Recent correlational studies suggest that night-to-night variability in sleep duration may be even more problematic than average duration. Experimental studies of sleep variability are needed to test these claims. However, the field lacks a demonstrably feasible protocol for inducing variable versus stable sleep in adolescents. Method(s): We piloted an at-home experimental protocol in healthy 14-17 year-olds that systematically varied night-to-night sleep variability while maintaining a constant average sleep duration across conditions. Participants completed a 5-night run-in period to establish a consistent morning wake time followed in randomly counterbalanced order by two 5-night spans in which (a) bedtimes and wake times were held constant to stabilize sleep duration (stable condition; STB) or (b) wake times were constant but bedtimes were adjusted nightly to introduce variability while maintaining the same average weekly sleep duration (variable condition; VAR). Sleep was monitored via actigraphy and sleep diary. Result(s): Of 21 participants randomized to an order of conditions, 20 completed the full study. For those 20, there was no difference in actigraphy- determined average sleep duration (in minutes) between STB (M=421.4) and VAR (M=419.7; p=.81) but participants had more variable sleep duration (SD in minutes across nights) during VAR than STB (77 vs. 30 minutes, p =30 minutes SD in night-to-night sleep during VAR. Conclusion(s): It is feasible to conduct an ecologically valid experimental protocol in healthy teens which allows for comparison of relatively stable versus variable sleep. This protocol controls for average sleep duration while still allowing for causal inference of the impact of variable sleep compared to stable sleep on youth functioning.