Night-waking and behavior in preschoolers: a developmental trajectory approach

Objective: The aim was to study, with a developmental approach, the longitudinal association between night-waking from age 2 to 5-6 years and behavior at age 5-6 years.

Methods: Within the French birth cohort study Etude sur les Déterminants pré et post natals du développement et de la santé de l'ENfant (EDEN), repeated measures of children's night-waking were collected at age 2, 3 and 5-6 through parental questionnaires and were used to model night-waking trajectories. Behavior was assessed with the "Strengths and Difficulties Questionnaire," which provides five subscales measuring a child's conduct problems, emotional symptoms, peer relation problems, antisocial behavior, and hyperactivity/attention problems. The behavioral subscales were dichotomized at the tenth percentile. Multivariable logistic regressions, adjusted for parents' socio-economic factors, parental characteristics, and children's characteristics and sleep habits allowed us to study, in 1143 children, the association between night-waking trajectories from 2 to 5-6 years and behavior at age 5-6 years.

Results: The "2 to 5-6 rare night-waking" trajectory represented 78% of the included population (n = 896), and the "2 to 5-6 common night-waking" 22% (n = 247%). Children belonging to the "2 to 5-6 common night-waking trajectory" had, at age 5-6, increased risk of presenting emotional symptoms (odds ratio [OR] = 2.17, 95% CI = 1.27-3.70, p = 0.004), conduct problems (OR = 1.63, 95% CI = 1.00-2.65, p = 0.050), and hyperactivity/attention problems (OR = 1.61, 95% CI = 1.00-2.57, p = 0.049). After adjusting for baseline behavior at age two years, only the association with emotional symptoms remained significant (OR = 2.02, 95% CI = 1.15-3.55, p = 0.015). Results did not differ according to sex.

Conclusion: Results suggest that the persistence of night-waking difficulties in early years is positively associated with emotional symptoms, hyperactivity/inattention, and conduct problems.