Two studies being presented as posters later this morning examine the negative impact of late bedtimes on teens.
One study (#1064) suggests that parental-mandated bedtimes could help protect teens from depression and suicidal thoughts by lengthening sleep duration. Results show that adolescents with parental-mandated bedtimes at midnight or later were 25 percent more likely (adjusted odds ratio 1.25) to suffer from depression and 20 percent more likely (adjusted odds ratio 1.20) to have suicidal ideation compared with adolescents who had parental-mandated bedtimes of 10 p.m. or earlier. Multivariate models show that sleep duration may have acted as a mediator of these associations; thus short sleep may be a risk factor for depression and suicidal ideation.
Another study (#0161) shows that being a “night owl” or “evening type” – preferring to go to bed late at night and wake up later in the day – is associated with lower academic performance in college and a decline in academic performance from college to high school. Results indicate that evening types had significantly lower first year college GPA (2.84) than “morning types” and “intermediate types” (3.18). They also slept on average 41 minutes less on school nights. For all students, “sleep hygiene” was related to academic performance.
You can download the SLEEP 2009 abstract supplement as an 11 MB file in PDF format.