Most Singaporean teens don’t get enough sleep on school nights
Less than 15 percent of Singaporean adolescents get the recommended 8–10 hours of sleep on a school night, reports a recent study, noting that such short sleep duration is linked to symptoms of depression, overweight or obesity, and poorer self-rated health.
“Improving nocturnal sleep behaviour is a major challenge in East Asian cultures, where the pursuit of academic success may be prioritized over sleep. Our findings show that most adolescents in this setting are chronically sleep-deprived,” said researchers, noting that this may be hindering these students from achieving their full potential.
In 2,313 school-age adolescents (mean age 16.0±1.6 years; 54.1 percent female) recruited from eight Singapore schools, only 14.8 percent (n=346) reported meeting the appropriate nightly sleep duration on schooldays. This was lower than the 79.7 percent who reported the same on weekends, during which the participants reported sleeping for an average of 2 hours longer. [Sleep Med 2018;doi:10.1016/j.sleep.2018.10.041]
Researchers found a positive dose-dependent correlation between school-night sleep duration and self-reported health. Significantly more students with age-appropriate sleep rated their health as good or excellent than those with moderate (7–<8 hours) or short (<7 hours) sleep (85.6 percent vs 75.6 percent vs 69.4 percent; p<0.001 for both).
Similar trends were observed for overweight/obesity. Those with short sleep were more than twice as likely to be overweight than those with appropriate sleep (adjusted odds ratio [OR], 2.56; 95 percent CI, 1.39–4.70). The effect in adolescents with moderate sleep duration was only of borderline significance (adjusted OR, 1.90; 0.99–3.66).
Sleep also had benefits for depressive symptoms. In an item-by-item analysis, all depression symptoms in the Kutcher Adolescent Depression Scale showed a negative and dose-dependent relationship with night-time sleep duration during school nights.
For instance, the likelihood of sadness (adjusted OR, 2.34; 1.52–3.60), irritability (adjusted OR, 2.52; 1.51–4.22) and lack of focus (adjusted OR, 4.33; 2.91–6.43), among other symptoms, were all significantly elevated in students with <7 vs 8–10 hours of nocturnal sleep.
“Our findings that sleep duration on school nights was associated with health-related measures may be especially important for convincing policymakers, educational professionals and parents in East Asia that short sleep is a problem worth addressing,” said researchers, however noting that since Asian countries consistently do well in global academic performance rankings, this may be a difficult case to make.
“To encourage better sleep practices in East Asian societies, it may be better to focus on the importance of sleep for adolescents’ mental health and holistic growth,” they said.
In a subsequent analysis, researchers sought to identify important barriers to achieving adequate sleep. They found that younger age, being enrolled in an international school, having a parent-determined bedtime, shorter study times (<3 hours), shorter daily travel times (≤30 minutes) and a later school start time were all important factors that contributed toward meeting the appropriate sleep duration (p<0.01 for all).
“Strategies for improving sleep in East Asian societies should take into consideration sociocultural factors that may affect the ability to remove barriers to healthy sleep,” said researchers.
“A multipronged approach may be necessary for improving sleep behaviour in adolescents, in which all stakeholders (students, parents, teachers, school leaders and policymakers) are involved in promoting behavioural change,” they added.