Abstract
Introduction: Adolescence is a period marked by significant changes in sleep patterns as a result of both their biology and environment. These changes often result in poor sleep quality and quantity, which can have negative impacts on adolescent health and well-being. The term "sleep quality" is often used in sleep research and clinical practice, but there is no precise definition and it can refer to both subjective and objective measures. Understanding objective sleep variables that might underlie sleep quality perceptions and related outcomes is important for many areas of sleep health, particularly as concerns National Sleep Foundation (NSF) sleep quality recommendations adopted by many countries worldwide are acknowledged to be based on limited availability of scientific data.
Aims: To investigate what objective measures of sleep correlate with subjective measures of sleep quality, satisfaction with sleep amount (sleep sufficiency) and next-day sleepiness, mood, and concentration.
Methods: Seventy-one healthy adolescents (aged 16-17 years) completed seven days and nights of actigraphy whilst simultaneously completing seven daily surveys rating the previous night’s sleep quality and sleep sufficiency, and next-day sleepiness, mood, and concentration. The relationship between eight actigraphy-derived sleep variables and subjective measures were analysed for both between and within- subject effects using logistic generalized estimating equation (GEE) models.
Results: Whilst between-subject analyses revealed several significant findings, total sleep time (TST) that measures the true amount of sleep, was the only objective measure significantly associated with subjective sleep quality and mood in within-subject analyses. For example, for every 1 h less sleep per night, teens were 1.56 (95% CI: 1.29, 1.88) times more likely to rate their next-day sleep quality as poor rather than good. Additionally, the number of awakenings was correlated with ratings of morning sleepiness OR = 1.26 (95% CI: 1.04, 1.54). We found no associations between sleep variables and ratings of daytime sleepiness, sleep sufficiency, and concentration. None of the NSF’s sleep metrics used to define good sleep quality in teenagers (e.g. sleep efficiency and related variables), linked with the subjective ratings of sleep quality.
Conclusions: To the best of our knowledge, this is the first study investigating what correlates of objective sleep measures link to subjective measures of sleep quality and related outcomes in an adolescent population. The findings suggest that the most important factor contributing to perceptions of sleep quality in adolescents is, in fact, sleep quantity.