Sleep Duration In Early Childhood Research Articles

Association of nighttime sleep with behaviors in Japanese early childhood.

Preschool children in Asian countries, including Japan, sleep for a shorter duration at night than those in Europe and the USA. We examined the effects of the nighttime sleep duration on behavioral development in early childhood in Japan. We used data from a large Japanese nationwide, population-based, longitudinal survey that began in 2001. We restricted the study participants to children born after 37 gestational weeks, with a birth weight ≥ 2500 g and singleton births (n=41 890). The nighttime sleep duration was examined at 2.5 years old. Responses to survey questions regarding age-appropriate behavior at 5.5 years old were used as indicators of behavioral development. We conducted logistic regression analyses with adjustment for confounding factors, with ≥11h of nighttime sleep as the reference group. The odds ratios for children who had ≤9 h of nighttime sleep, which was associated with being unable to listen with fidgeting and being unable to remain patient, were 1.26 (95% confidence interval, 1.14-1.39) and 1.27 (1.16-1.38), respectively. Children who had an irregular nighttime sleep duration were associated with age-appropriate behavioral inabilities. These results were similar in children who usually and sometimes took naps to those before stratification by the frequency of napping. A short nighttime sleep duration especially affects hyperactivity and impulsivity. An irregular nighttime sleep duration increases the inability to perform overall age-appropriate behaviors more than a short sleep duration. Ensuring a regular and sufficient nighttime sleep duration in early childhood is important for healthy behavioral development.

Short or Irregular Sleep Duration in Early Childhood Increases Risk of Injury for Primary School-Age Children: A Nationwide Longitudinal Birth Cohort in Japan.

The aim of this study was to investigate the longitudinal relationship between shorter or irregular sleep duration (SD) in early childhood and increased risk of injury at primary school age using data from a nationwide survey in Japan. We categorized SD into seven groups: 6 h, 7 h, 8 h, 9 hrs, 10 or 11 h, >12 h, and irregular, based on questionnaire responses collected at 5.5 years old. The relationship between SD and incidence of injury at 5.5–nine years of age is shown. In addition, we completed a stratified analysis on children with or without problematic behavior at eight years old. We included 32,044 children, of which 6369 were classified as having an injury and 25,675 as not having an injury. Logistic regression model showed that shorter or irregular SD categories were associated with an increased adjusted odds ratio (aOR) for injuries (6 h: aOR 1.40, 95% confidence interval (CI) 1.19–1.66, 7 h: aOR 1.10, 95% CI, 0.98–1.23, 8 h: aOR 1.13, 95% CI, 1.02–1.26, irregular: aOR 1.26, 95% CI 1.10–1.43). The same tendency was observed with shorter or irregular SD in subgroups with or without behavioral problems. Shorter or irregular sleep habits during early childhood are associated with injury during primary school age.

Longitudinal correlates of sleep duration in young children

ObjectiveThe primary aim of this study was to longitudinally examine potential demographic and screen time correlates of nap duration, nighttime sleep duration, and total sleep duration in young children over two time points. MethodsData from the supporting Healthy physical AcTive Childcare setting (HATCH) study were analyzed. Participants were 206 toddlers (19–35 months) and preschoolers (36–60 months) in Alberta and Ontario, Canada. Child age, screen time (television, video games), and sleep duration (nap, nighttime) were measured at baseline and six-month follow-up, while other demographic variables were assessed at baseline only using the HATCH parental questionnaire. Mixed models were performed to examine the associations between potential correlates and sleep duration over time. ResultsIn the multiple regression models, significant correlates of total sleep duration (min/d) were child age (months; B = −3.03; 95%CI:-3.88,-2.19) and parental education (bachelor's degree vs. below bachelor level; B = 29.74, 95%CI:7.43,52.06). Significant correlates of nighttime sleep duration (min/d) included child age (B = −0.81; 95CI%:-1.53,-0.10), child race/ethnicity (Caucasian vs. non-Caucasian; B = 15.31; 95%CI:0.38,30.25), household income (>$150,000 vs. <$50,000; B = 32.93, 95%CI:9.80,56.06), television time (B = −0.19, 95%CI:-0.32,-0.05), video games time (B = −0.19, 95%CI: −0.38, −0.01) and total screen time (B = −0.19; 95%CI:-0.29,-0.08). Significant correlates of nap duration (min/d) were child age (B = −2.10; 95%CI:-2.68,-1.51) and race/ethnicity (Caucasian vs. non-Caucasian; B = −13.73; 95%CI:-25.78,-1.68). ConclusionYoung children who were non-Caucasian, from lower income families, who had less-educated parents, or who had more screen time tended to have shorter sleep duration. Targeting these demographic groups and screen time appears important for promoting adequate sleep duration in early childhood.

Sleep Difficulties in Infancy Are Associated with Symptoms of Inattention and Hyperactivity at the Age of 5 Years: A Longitudinal Study.

ABSTRACT:Objective:Sleep difficulties are associated with cognitive and behavioral problems in childhood. However, it is still unclear whether early sleep difficulties are related to later development. We studied whether parent-reported sleep duration, night awakenings, and parent-reported sleep problems in early childhood are associated with symptoms of inattention and hyperactivity at the age of 5 years.Method:Our study is based on the Child-Sleep birth cohort initially comprising 1673 families, of which 713 were retained at the age of 5 years. We used the Brief Infant Sleep Questionnaire and the Infant Sleep Questionnaire, which were filled out by the parents when their child was 3, 8, and 24 months and 5 years old. Symptoms of inattention and hyperactivity at the age of 5 years were assessed using the Strengths and Difficulties Questionnaire and the Five-to-Fifteen questionnaire.Results:Sleep duration at the age of 3, 8, and 24 months was associated with inattentiveness at 5 years of age. Moreover, parent-reported sleep problems at the age of 24 months were related to both inattentive and hyperactive symptoms at the age of 5 years. Finally, at the age of 5 years, parent-reported sleep problems and night awakenings were associated with concurrent symptoms of inattention and hyperactivity.Conclusion:Our findings suggest that certain sleep characteristics related to sleep quality and quantity in early childhood are associated with inattentiveness and hyperactivity at the age of 5 years. Interestingly, sleep duration in early childhood is consistently related to inattention at the age of 5 years.

Gestational age at birth and sleep duration in early childhood in three population-based cohorts

BackgroundBoth preterm and post-term births have been associated with neonatal morbidity and mortality, including adverse impact on neurodevelopment. Important neural maturational processes take place during sleep in newborns, but findings on gestational duration and sleep in early childhood are contradictory and often derive from small clinical samples. We studied the association of gestational age at birth with sleep duration in early childhood in three population-based cohorts. MethodsGestational age at birth and sleep duration were assessed in three population-based cohort studies in The Netherlands (n = 6471), Singapore (n = 862), and Canada (n = 583). Gestational age at birth was assessed using ultrasound in pregnancy in combination with date of birth, and caregivers repeatedly reported on child sleep duration at three, six, 24, and 36 months of age. Generalized estimating equations were used, which were adjusted for confounders, and findings were pooled in a meta-analysis. ResultsChildren born preterm (<37 weeks of gestation) showed longer sleep duration than children born at term; and children born post-term (≥42 weeks of gestation) showed shorter sleep duration. The meta-analysis indicated a small negative effect of gestational age on child sleep duration (effect size −0.11), when assessed in children born at term only. ConclusionIn early childhood, children with a lower gestational age have a longer sleep duration, even when they are born at term (37–42 weeks of gestation). These subtle yet consistent findings point to the importance of maturational processes during sleep, not only in premature children but also in children born at term after shorter gestational duration.

The Joint Association of Small for Gestational Age and Nighttime Sleep with Blood Pressure in Childhood

Children born small for gestational age (SGA) are more likely to develop high blood pressure. In prior studies, longer sleep duration is associated with lower BP, and SGA is associated with shorter sleep duration in childhood. We investigated whether sleep duration in early childhood modifies the association between SGA and higher childhood SBP in 1178 children recruited at birth and followed up to age 9 years. We ascertained birthweight and gestational age from medical records. We derived child sleep duration from maternal questionnaire interview. We calculated child SBP percentile according to U.S. reference data. We defined elevated SBP as SBP ≥75th percentile. In this sample, 154 (13.1%) children were born SGA. Children born SGA had higher SBP percentiles and higher risk of elevated SBP. Among children born SGA, those in the highest compared to the lowest tertile for sleep had a 12.28 lower (−22.00, −2.57) SBP percentile and 0.44 (0.25 to 0.79) times lower risk of developing elevated SBP. Our data are consistent with an interaction between SGA and sleep duration on childhood elevated SBP (Pinteraction = 0.0056). In conclusion, in this prospective birth cohort, longer sleep duration in early childhood may mitigate the blood pressure-raising effect of being born small.

Longitudinal Associations of Sleep Duration in Infancy and Early Childhood with Body Composition and Cardiometabolic Health at the Age of 6 Years: The Generation R Study.

A short sleep duration is associated with a higher obesity risk from midchildhood onward. However, whether sleep duration in early childhood is associated with body composition and cardiometabolic health remains unclear. This study aims to examine the prospective association of sleep duration in infancy and early childhood with body composition and cardiometabolic health at 6 years of age. Data were available for 5161 children from a population-based cohort in the Netherlands. Sleep duration was assessed at ages 2, 6, 24, and 36 months by parental reports. When children were 6 years old, measures of body composition (iDXA), blood pressure, insulin, and lipid levels were collected. Longitudinal associations among sleep duration, body composition, and cardiometabolic health were studied with multivariable linear regression analyses. In addition, potential bidirectional associations between sleep duration and BMI were studied by using cross-lagged modeling. Shorter sleep duration at 2 months predicted higher BMI and fat mass in 6-year-old children, accounting for confounders and BMI at 2 months (e.g., for BMI, per hour sleep, B = -0.018, 95% CI = -0.026; -0.009). No temporal relationships among sleep duration at other ages, later body composition, and cardiometabolic outcomes were found. The cross-lagged model indicated a bidirectional association between sleep duration and BMI in early life (2 to 6 months of age). Shorter sleep duration at 2 months, but not at later ages, predicted poorer body composition 6 years later. We found no clear evidence for an effect of sleep duration in early life on cardiometabolic health.

Longitudinal Analysis of Sleep Duration and Cardiometabolic Risk in Young Children.

The aim of this study is to determine if sleep duration in early childhood is associated with cardiometabolic risk (CMR) in later childhood as assessed by a CMR cluster score [sum of age- and sex-standardized z-scores of waist circumference (WC), systolic blood pressure, triglycerides, glucose, and (inverse) high-density lipoprotein (HDL)]. Secondary objectives included examining sleep duration and the individual CMR factors and BMI z-score. A prospective cohort study was conducted using data from the TARGet Kids! practice-based research network in Toronto, Canada. Children (n = 597) with parent-reported 24-hour sleep duration in early childhood (12-36 months) and a follow-up visit (36-96 months) with all five CMR factors were included in the analysis. Multivariable linear regression was used to assess the relationship between early childhood sleep duration and later childhood CMR, adjusting for relevant covariates. Average 24-hour sleep duration in early childhood [mean age: 28.1 (6.6) months] was 11.8 (1.4) hours, with 87% meeting or exceeding total sleep recommendations for their age. Sleep duration in early childhood was not associated with the CMR cluster score in later childhood. Shorter sleep duration was associated with higher HDL concentrations [adjusted β = -0.028 (95% confidence interval: -0.049 to -0.007), p = 0.009]. Further research is needed to determine if early childhood sleep duration is associated with HDL in later childhood. Future studies, which investigate sleep quality in addition to sleep duration, may be helpful.

Sleep patterns and obesity in childhood.

To highlight the recent findings on sleep-obesity associations in children. We focus on sleep duration, sleep timing and chronotype, and describe the potential mechanisms underlying sleep-obesity associations. Poor sleep is increasingly common in children and associations between short sleep duration in early childhood and obesity are consistently found. Less is known about the infancy period, and the findings in adolescents are inconsistent. Sleep timing patterns may also contribute to obesity risk. Variable and shifted sleep schedules and evening chronotypes have recently been linked to adiposity in adults; less is known about children. Further, there is little understanding regarding the mechanisms of association. The timing of eating, dietary intake, obesogenic eating behaviors, and changes in appetite-regulating hormones have been identified as possible mechanisms for sleep-obesity associations and may be promising avenues for future research. Longitudinal and experimental work with children is needed to determine the nature of associations. Beyond sleep duration, sleep timing patterns may contribute to obesity risk. Biological and behavioral processes have been proposed as mechanisms that may explain the association. Understanding the pathways through which poor sleep patterns could increase obesity risk in children may provide novel avenues for intervention.

Genetic and Environmental Influences on Daytime and Nighttime Sleep Duration in Early Childhood

To determine the relative contributions of genetic and environmental factors on daytime and nighttime continuous sleep duration at 6, 18, 30, and 48 months of age, and to identify different subgroups of children who followed different daytime and nighttime sleep duration trajectories and to investigate their etiology. The current study included 995 twins (405 monozygotic and 586 dizygotic) of the Quebec Newborn Twin Study recruited from the birth records of the Quebec Statistics Institute. Daytime and nighttime sleep was assessed through maternal reports at 6, 18, 30, and 48 months of age. A semiparametric modeling strategy was used to estimate daytime and nighttime sleep duration trajectories. Quantitative genetic models were used to examine to what extent genetic and environmental factors influenced daytime and nighttime continuous sleep duration. Genetic modeling analyses revealed environmental influences for all daytime sleep duration trajectories. In contrast, strong genetic influences were found for consolidated nighttime sleep duration (except at 18 months and for the short-increasing sleep duration trajectory). This is the first indication that early childhood daytime sleep duration may be driven by environmental settings, whereas the variance in consolidated nighttime sleep duration is largely influenced by genetic factors with a critical environmental time-window influence at ∼18 months.

Genetic and Environmental Influences on Daytime and Nighttime Sleep Duration in Early Childhood

Genetic and Environmental Influences on Daytime and Nighttime Sleep Duration in Early Childhood

Associations between the macronutrient composition of the evening meal and average daily sleep duration in early childhood

Short sleep duration in early childhood may increase the risk for chronic diseases in later life. Strategies to improve sleep duration are thus of interest. We investigated whether the nutritional composition of the evening meal is associated with children's sleep duration in the 2nd year of life. Multivariable regression models included 594 participants of the DONALD Study with 3-days weighed dietary records and average daily sleep duration at age 1.5 and 2 years. Higher energy intakes with the evening meal were associated with a longer sleep duration (1min/10kcal, p=0,01). With respect to absolute intakes, carbohydrates (0.8min/g, p<0.0001), especially from high GI foods (1.3min/g, p<0.01), and a higher GL (1.5min/g GL, p<0.01) were accompanied by longer sleeping time. A qualitative exchange of energy from protein by energy from carbohydrates from high GI foods was only associated with increased sleep duration in toddlers without (1.9min/%E, p<0.05), but not with nightly eating occasions (p>0.4). The observed associations are in line with suggested sleep-improving effects of carbohydrates. Effect sizes suggest that the clinical relevance of nutritional composition for sleep duration is limited in healthy young toddlers. These observations and their possible importance for more vulnerable groups need to be confirmed in clinical trials.

Longitudinal associations between reported sleep duration in early childhood and the development of body mass index, fat mass index and fat free mass index until age 7

Epidemiological studies in children and adolescents have revealed short sleep duration as a risk factor for weight gain. However, only few studies have addressed sleep in early childhood. Our aim was to determine whether sleep in the second year of life is associated with the development of body composition throughout childhood. Analysis included 481 DONALD participants with parental reported data on sleep duration and annually measured body composition until age 7. Using median splits of sleeping time at 1.5 and 2 years we defined sleep duration categories: consistently short (CS, n = 122), inconsistent (I, n = 143) and consistently long (CL, n = 216). Polynomial mixed effects regression models were used to analyze differences in the trajectories of body mass index (BMI, kg/m(2)), fat mass index (FMI, kg/m(2)) and fat free mass index (FFMI, kg/m(2)) from ages 2-7 years between the sleep duration categories. Compared to CL-children, CS-sleepers differed in their FMI development with respect to linear, quadratic and cubic trend (all p < 0.04), resulting in progressively higher FMI levels until age 7 independently of early life or socioeconomic factors. Trajectories of BMI and FFMI did not differ between the sleep duration categories. Consistently short sleep duration in the critical window of early childhood appears to exert a moderate but sustained adverse effect on the development of fat mass - but not fat free mass - until age 7.