Doctor: Eve Reynaud
Title: Study of nocturnal awakenings and behavior of the child aged 2 to 5 in the EDEN cohort : a developmental approach
Supervisor: Sabine Plancoulaine
Doctoral school: ED 393 Epidemiology and Biomedical Information Sciences, Université Paris Cité
Date of thesis defense: 27/09/2017
Jury: Sabine Plancoulaine, Maria Melchior, Bruno Falissard, Carmen Schröder, Karen Spruyt, Michel Lecendreux
The structure of sleep evolves greatly in the first years of life. Occasional nightwaking is thus normal in young children, but waking-up every other night or more is considered adversely frequent. The scientific literature suggests that frequent night-waking is associated with concomitant behavioral difficulties in children. Yet, little is known about the evolution of night-waking in preschool years and its longitudinal association with behavior. Objectives: To model the evolution of night-waking between the age of 2 and 5-6 years and explore the association with family and child related factors. To analyze the associations between night-waking trajectories and behavior before school entry. Population and methods: Analyses were based on the French birth-cohort study EDEN, which recruited 2 002 pregnant women between 2003 and 2006 in the maternity of Poitiers and Nancy. Information regarding night-waking and behavior were assessed using parental questionnaires at the ages of 2, 3 and 5-6 years. The « group based trajectory modeling » method allowed us to model the evolution of night-waking and of inattention/hyperactivity, describing different developmental trends between the age of 2 and 5-6 years. The associations between night-waking trajectories, family and child related factors and behavior, were analyzed using logistic regressions, adjusted on potential confounding factors. Results: Two distinct night-waking trajectories were identified in children between the age of 2 and 5-6 years. One, named « rare night-waking », represented 77% of the children. This group followed a linear trajectory, which was close to zero and slightly declining with time. The second trajectory, named « common night-waking », represented 23% of the children. It was higher than the first trajectory at each time-point, and a peak was observed at age 3. Risk factors for belonging to the « common night-waking » trajectory were life-style related factors: exposures to second hand smoking, collective care arrangement, and time spent in front of the television. Children belonging to the common night-waking trajectory had higher risk of having emotional symptoms, conduct problems and inattention/hyperactivity at age 5-6. No associations were found with prosocial behavior nor peer-relationship problems. Three trajectories of inattention/hyperactivity were identified, a low, an intermediate and a high one, all stable in time. The risk of belonging to a high inattention/hyperactivity trajectory, compared to a low one, were four time more important for children with a « common night-waking » trajectory. Conclusion: Night-waking and inattention/hyperactivity persist in preschool years. A common night-waking trajectory during this period is a risk factor of diverse behavioral difficulties: emotional symptoms, conduct problems and inattention/hyperactivity. The latter co-evolves with night-waking. Our results highlight the importance of identifying sleep problems in early years, especially in the presence of behavioral difficulties.