Questionnaire survey on sleep habits of 3-year-old children in Asahikawa City: Comparison between 2005 and 2020.

Background: Good sleep is essential for children's healthy growth. In 2005, we conducted a questionnaire survey on children's sleep habits and their background, targeting parents who attended health checkups for their 3-year-old children in Asahikawa City, Hokkaido. In 2020, we performed a secondary survey, including additional questions regarding media usage. We analyzed changes in children's sleep environment by comparing the results of both surveys.

Methods: Children from 500 families (n = 420; 219 males, 201 females; mean age, 3.6 years) who underwent 3.5-year-old health checkups (per the changed schedule in 2015) in Asahikawa City from July 2020 to November 2020 and their parents who had completely answered the questionnaire were included.

Results: The proportion of children who used childcare support system such as nursery schools or kindergarten increased from 30% in the previous survey to 95% in the present survey. The mean nocturnal sleep duration of children was 9.33 h in the present survey, 0.77 h shorter than that in the previous survey; similar to the previous survey results, it was significantly short (8.71 h) in children who went to bed after 10 PM. Moreover, it was significantly short in children who watched television for more than two hours or used media within two hours before going to bed or if parents used smartphones or watched motion pictures for >30 min/day. The rate of consulting pediatricians regarding sleep problems decreased from 3% to 2.4%.

Conclusion: Parents' lifestyles greatly influenced children's sleep habits in 2020. Pediatricians should actively participate in managing children's sleep problems.