Sleep disturbances in 5-year-old children: insufficient sleep, insomnia symptoms and associated factors

Abstract

Background Up to 50 % of preschool-aged children experience sleep problems but recent studies on sleep disturbances of 5-year-olds, and particularly in Northern Europe, are limited. Our aim was to determine how 5-year-old children sleep in Finland by identifying the most common sleep disturbances and examining factors associated with insomnia symptoms. Methods This cross-sectional study included 714 five-year-old children from the CHILD-SLEEP birth cohort. The main outcome measures from parent-filled questionnaires were sleep durations, bedtimes and wake-up times, naps, sleep habits and sleep-related symptoms, the latter assessed using the Sleep Disturbance Scale for Children (SDSC). Factors associated with insomnia symptoms were analyzed using chi-square tests and logistic regression adjusted for age, sex, and further for siblings, daycare attendance and single parenthood. Insomnia symptoms were defined as SDSC subscale of Disorders of Initiating and Maintaining Sleep sum ≥90th percentile for analyses. Results Overall, 43.0 % (N = 292) of children experienced at least one sleep-related problem occurring three or more times per week. Almost one-fourth (23.3 %) slept less than the recommended minimum of 10 h total. At least one individual SDSC insomnia symptom occurring ≥3 times per week was present in 18 % of children, with sleep onset problems being the most prevalent symptom. Regular naps showed the strongest association with DIMS insomnia symptoms (p < 0.001; crude model OR 2.70, 95 % Cl 1.58–4.85, adjusted model 1 OR 2.70, 95 % Cl 1.52-4.77; adjusted model 2 OR 2.75, 95 % Cl 1.54-4.92) while different parent-dependent sleep pattern variables were also associated. Circadian rhythm problems were uncommon. Conclusion Attention should be paid to insomnia symptoms and particularly short total sleep duration among 5-year-olds by considering the role of daytime sleep and evaluating factors that may interfere with independent sleep.