Null Association Between Isolated Orofacial Clefts and Sleep Duration: A Cohort Study From the Japan Environment and Children's Study.

Although children with orofacial clefts have an increased risk for sleep-disordered breathing, no studies have examined the association of sleep duration. Thus, this study aimed to examine associations between orofacial clefts and sleep duration at 1 month, 6 months, 1 year, and 3 years of age in Japan.A cohort study from the Japan Environment and Children's Study.This study consisted of 91 497 children, including ones with isolated cleft lip and palate (n = 69), isolated cleft lip only (n = 48), and isolated cleft palate only (n = 37), for which recruitment was undertaken during 2011 to 2014.Seep durations (hours per day) at 1 month, 6 months, 1 year, and 3 years of age, as reported by their mothers.In the control group, mean sleep durations and standard deviations at 1 month, 6 months, 1 year, and 3 years of age were 15.2 (2.5), 13.6 (1.9), 12.9 (1.6), and 11.6 (1.2) h, respectively. Compared to the control group, linear regression models reported effect sizes and 95% confidence intervals shorter than 1 h for sleep duration of each type of isolated orofacial cleft at each time point.This study suggested null associations between isolated orofacial clefts and sleep duration at 1 month, 6 months, 1 year, and 3 years of age. Children with isolated orofacial clefts had sufficient mean sleep duration.