Difficulties in getting to sleep, late bedtime and sleep duration among adolescents in Latvia

Abstract Background Sleep is important for adolescent general wellbeing and different sleep domains like difficulties in getting to sleep, bedtime resistance and sleep duration can be studied. This study investigates the prevalence of weekly difficulties in getting to sleep in association with bedtime and sleep duration on schooldays and weekends among adolescents in Latvia. Methods Data from the HBSC Survey 2017/2018 of Latvia with 4412 respondents aged 11, 13 and 15 years were used for statistical analysis. Sleep duration less than 7h was classified as insufficient and bedtime at 0:00 or later as delayed bedtime. Age-adjusted logistic regression and adolescents without weekly difficulties in getting to sleep as a reference was used for studying the associations. Results On average, 43.6% of adolescents (38.0% boys and 49.1% girls) reported weekly difficulties in getting to sleep. Of those, 26.5% reported sleep duration <7h on schooldays but 5.6% on weekends. On average, difficulties in getting to sleep was associated with the increased odds of insufficient sleep duration on schooldays (OR = 2.16; 95%CI 1.84-2.54) and weekends (OR = 1.66; 95%CI 1.23-2.24), with higher odds in girls than boys. Delayed bedtime was significantly more prevalent among adolescents with sleep difficulties than for those without (33.7% vs 20.6%). The sleep duration <7h was more prevalent among those adolescents having sleep difficulties and delayed bedtime than in those with sleep difficulties and bedtime before 0:00, both on schooldays (72.1% vs 3.2%) and weekends (7.9% vs 0%). Conclusions Difficulties in getting to sleep among adolescents are highly prevalent and increases the odds of insufficient sleep duration, especially in girls. Delayed bedtime seems to modify the association between the difficulties in getting to sleep and sleep duration. Key messages Adolescents with difficulties in getting to sleep are at risk of delayed bedtimes and insufficient sleep duration. Further studies to explore the underlying mechanisms linking difficulties in getting to sleep and delayed bedtime are required.