Patterns of perinatal polyunsaturated fatty acid status and associated dietary or candidate-genetic factors.

Perinatal exposure to omega-3 and omega-6 polyunsaturated fatty acids (PUFAs) can be characterized through biomarkers in maternal or cord blood or breast milk. Objectives were to describe perinatal PUFA status combining multiple biofluids and to investigate how it was influenced by dietary intake during pregnancy and maternal FADS and ELOVL gene polymorphisms. This study involved 1,901 mother-child pairs from the EDEN cohort, with PUFA levels measured in maternal and cord erythrocytes, and colostrum. Maternal dietary PUFA intake during the last trimester was derived from a food frequency questionnaire. Twelve single-nucleotide polymorphisms in FADS and ELOVL genes were genotyped from maternal DNA. Principal component analysis incorporating PUFA levels from the three biofluids identified patterns of perinatal PUFA status. Spearman's correlations explored associations between patterns and PUFA dietary intake, and linear regression models examined pattern associations with FADS or ELOVL haplotypes. Five patterns were retained: "High omega-3 LC-PUFAs, low omega-6 LC-PUFAs"; "Omega-6 LC-PUFAs"; "Colostrum LC-PUFAs"; "Omega-6 precursor (LA) and DGLA"; "Omega-6 precursor and colostrum ALA". Maternal omega-3 LC-PUFA intakes were correlated with "High omega-3 LC-PUFAs, low omega-6 LC-PUFAs" (r(DHA) = 0.33) and "Omega-6 LC-PUFAs" (r(DHA) = -0.19) patterns. Strong associations were found between FADS haplotypes and PUFA patterns except for "High omega-3 LC-PUFAs, low omega-6 LC-PUFAs". Lack of genetic association with the "High omega-3 LC-PUFAs, low omega-6 LC-PUFAs" pattern, highly correlated with maternal omega-3 LC-PUFA intake, emphasizes the importance of adequate omega-3 LC-PUFA intake during pregnancy and lactation. This study offers a more comprehensive assessment of perinatal PUFA status and its determinants.

Sleep duration in preschool age and later behavioral and cognitive outcomes: an individual participant data meta-analysis in five European cohorts.

Short sleep duration has been linked to adverse behavioral and cognitive outcomes in schoolchildren, but few studies examined this relation in preschoolers. We aimed to investigate the association between parent-reported sleep duration at 3.5 years and behavioral and cognitive outcomes at 5 years in European children. We used harmonized data from five cohorts of the European Union Child Cohort Network: ALSPAC, SWS (UK); EDEN, ELFE (France); INMA (Spain). Associations were estimated through DataSHIELD using adjusted generalized linear regression models fitted separately for each cohort and pooled with random-effects meta-analysis. Behavior was measured with the Strengths and Difficulties Questionnaire. Language and non-verbal intelligence were assessed by the Wechsler Preschool and Primary Scale of Intelligence or the McCarthy Scales of Children's Abilities. Behavioral and cognitive analyses included 11,920 and 2981 children, respectively (34.0%/13.4% of the original sample). In meta-analysis, longer mean sleep duration per day at 3.5 years was associated with lower mean internalizing and externalizing behavior percentile scores at 5 years (adjusted mean difference: - 1.27, 95% CI [- 2.22, - 0.32] / - 2.39, 95% CI [- 3.04, - 1.75]). Sleep duration and language or non-verbal intelligence showed trends of inverse associations, however, with imprecise estimates (adjusted mean difference: - 0.28, 95% CI [- 0.83, 0.27] / - 0.42, 95% CI [- 0.99, 0.15]). This individual participant data meta-analysis suggests that longer sleep duration in preschool age may be important for children's later behavior and highlight the need for larger samples for robust analyses of cognitive outcomes. Findings could be influenced by confounding or reverse causality and require replication.

Family-focused contextual factors associated with lifestyle patterns in young children from two mother-offspring cohorts: GUSTO and EDEN.

BACKGROUND: Integrated patterns of energy balance-related behaviours of preschool children in Asia are sparse, with few comparative analyses. PURPOSE: Using cohorts in Singapore (GUSTO) and France (EDEN), we characterized lifestyle patterns of children and investigated their associations with family-focused contextual factors. METHODS: Ten behavioural variables related to child's diet, walking, outdoor play and screen time were ascertained by parental questionnaires at age 5-6 years. Using principal component analysis, sex-specific lifestyle patterns were derived independently for 630 GUSTO and 989 EDEN children. Contextual variables were organised into distal (family socio-economics, demographics), intermediate (parental health, lifestyle habits) and proximal (parent-child interaction factors) levels of influence and analysed with hierarchical linear regression. RESULTS: Three broadly similar lifestyle patterns were identified in both cohorts: "discretionary consumption and high screen time", "fruit, vegetables, and low screen time" and "high outdoor playtime and walking". The latter two patterns showed small differences between cohorts and sexes. The "discretionary consumption and high screen time" pattern was consistently similar in both cohorts; distal associated factors were lower maternal education (EDEN boys), no younger siblings (GUSTO boys) and Malay/Indian ethnicity (GUSTO), while intermediate and proximal associated factors in both cohorts and sexes were poor maternal diets during pregnancy, parents allowing high child control over food intake, snacking between meals and having television on while eating. CONCLUSIONS: Three similar lifestyle patterns were observed among preschool children in Singapore and France. There were more common associated proximal factors than distal ones. Cohort specific family-focused contextual factors likely reflect differences in social and cultural settings. Findings will aid development of strategies to improve child health.

TV, computer, tablet and smartphone use and autism spectrum disorder risk in early childhood: a nationally-representative study.

BACKGROUND: Screen media use in early childhood has largely increased in recent years, even more so during the COVID-19 epidemic, and there is much discussion regarding its influence on neurodevelopment, including Autism Spectrum Disorder (ASD). METHODS: We examined the relationship between use of TV, computer, tablet and smartphone at age 2 years and risk of ASD assessed in telephone-based questionnaires among 12,950 children participating in the nationally representative ELFE ('Etude Longitudinale Française sur les Enfants') birth cohort study in France. RESULTS: In inverse-probability weighted (IPW) multinomial regression analyses, children's weekly or daily screen media use was associated with an increased likelihood of an intermediate risk of ASD (IPW-controlled OR for weekly use:1.07, 95% CI 1.02-1.12; IPW-controlled OR for daily use:1.05, 95% CI 1.02-1.08) but inversely associated with a high risk (IPW-controlled OR for weekly use: 0.60, 95% CI 0.50-0.73; IPW-controlled OR for daily use: 0.75, 95% CI 0.62-0.91), as ascertained by the M-CHAT. This was confirmed when studying TV as well as computer/tablet exposure separately. CONCLUSIONS: Overall, our nationally-representative study conducted among a large sample of 2-year-old children, indicates a complex relationship between screen exposure and ASD risk.

Night-sleep Duration Trajectories and Behavior in Preschoolers: Results from a Prospective Birth Cohort Study.

Background: Short sleep duration is associated with concomitant behavioral difficulties, but the longitudinal association between sleep duration and later behavior in early childhood remains unclear. The aim was to study the association between sleep duration trajectories throughout preschool and behavior at age 5-6 years.Participants: 1021 children of the French birth-cohort EDEN were included in this study.Methods: Night-sleep duration trajectories were modeled on the basis of repeated measures collected at age 2, 3 and 5-6 years by parental questionnaires. Behavior was assessed with the Strengths and Difficulties Questionnaire (SDQ), with five subscales measuring conduct problems, emotional symptoms, peer relation problems, antisocial behavior, and hyperactivity-inattention problems. The subscales were dichotomized by the 25th percentile. Multivariable logistic regression, adjusted for baseline behavior, and assessment of multiple confounding factors allowed for studying the independent association between night-sleep duration trajectories from age 2 to 5-6 and behavior at age 5-6.Results: Five distinct sleep-duration trajectories were identified. At age 5-6 years, probability of hyperactivity-inattention problems was increased for boys belonging to the "short sleep" and "medium-low sleep" duration trajectory and girls belonging to the "changing sleep" duration trajectory as compared with children with the medium-high sleep duration trajectory (boys: OR 2.69 [95% CI 1.18-6.16], p = .03 and 1.95 [1.25-3.03], p = .003, and girls: OR 2.79 [1.09- 7.17], p = .03). No associations were observed with the other SDQ subscales.Conclusion: The persistence of short night-sleep durations in preschool years as well as a sudden decrease at age 3 are risk factors of hyperactivity-inattention problems at school start.Abbreviations: SS: short-sleep duration trajectory; MLS: medium-low-sleep duration trajectory; MHS: medium-high-sleep duration trajectory; LS: long-sleep duration trajectory; CS: changing-sleep duration trajectory.

Infant feeding practices and sleep at 1 year of age in the nationwide ELFE cohort.

Sleep problems reported by parents affect 20% to 30% of infants. Few studies focused on the longitudinal association between infant feeding practices and sleep, especially in France. Analyses were based on 8,696 infants from the French national birth cohort ELFE. Collection of feeding practices from birth to 10 months allowed for the identification of trajectories of use of baby cereals and thickened formula by group-based trajectory modelling and calculation of duration of any breastfeeding (BF) and age at complementary feeding introduction (CFI) excluding baby cereals. Total sleep duration (TSD), night waking (NW) and sleep onset difficulties (SOD) were reported at age 1. Associations between feeding and sleep were tested by multinomial logistic regressions. BF duration ≥6 months was associated with parent-reported frequent NW, SOD and TSD ≤ 12 h/24 h at age 1. For TSD and SOD, this association was no longer significant after accounting for parental sleep-related practices. Early use of baby cereals (≤5 months) was associated with poor sleep. Early CFI (<4 months) was associated with shorter TSD and SOD but not NW. Early use of thickened formula (only <6 months) was related to poor sleep at age 1 (NW and SOD), whereas late (around 6 months) use of thickened formula was associated with better sleep. BF duration ≥6 months was related to poor sleep at age 1 but not after adjustment on 1-year parental sleep-related practices except for NW. The use of baby cereals or early CFI was not related to better sleep at age 1.

Clusters of diet, physical activity, television exposure and sleep habits and their association with adiposity in preschool children: the EDEN mother-child cohort.

BACKGROUND: Despite the growing interest in the relation between adiposity in children and different lifestyle clusters, few studies used a longitudinal design to examine a large range of behaviors in various contexts, in particular eating- and sleep-related routines, and few studies have examined these factors in young children. The objectives of this study were to identify clusters of boys and girls based on diet, sleep and activity-related behaviors and their family environment at 2 and 5 years of age, and to assess whether the clusters identified varied across maternal education levels and were associated with body fat at age 5. METHODS: At 2 and 5 years, respectively, 1436 and 1195 parents from the EDEN mother-child cohort completed a questionnaire including behavioral data. A latent class analysis aimed to uncover gender-specific behavioral clusters. Body fat percentage was estimated by anthropometric and bioelectrical impedance measurements. Association between cluster membership and body fat was assessed with mutivariable linear regression models. RESULTS: At 2 years, two clusters emerged that were essentially characterized by opposite eating habits. At 5 years, TV exposure was the most distinguishing feature, but the numbers and types of clusters differed by gender. An association between cluster membership and body fat was found only in girls at 5 years of age, with girls in the cluster defined by very high TV exposure and unfavorable mealtime habits (despite high outdoor playing and walking time) having the highest body fat. Girls whose mother had low educational attainment were more likely to be in this high-risk cluster. Girls who were on a cluster evolution path corresponding to the highest TV viewing time and the least favorable mealtime habits from 2 to 5 years of age had higher body fat at 5 years. CONCLUSIONS: Efforts to decrease TV time and improve mealtime routines may hold promise for preventing overweight in young children, especially girls growing up in disadvantaged families. These preventive efforts should start as early in life as possible, ideally before the age of two, and should be sustained over the preschool years.

Human TRAF3 adaptor molecule deficiency leads to impaired Toll-like receptor 3 response and susceptibility to herpes simplex encephalitis.

Tumor necrosis factor (TNF) receptor-associated factor 3 (TRAF3) functions downstream of multiple TNF receptors and receptors that induce interferon-α (IFN-α), IFN-ß, and IFN-λ production, including Toll-like receptor 3 (TLR3), which is deficient in some patients with herpes simplex virus-1 encephalitis (HSE). Mice lacking TRAF3 die in the neonatal period, preventing direct investigation of the role of TRAF3 in immune responses and host defenses in vivo. Here, we report autosomal dominant, human TRAF3 deficiency in a young adult with a history of HSE in childhood. The TRAF3 mutant allele is loss-of-expression, loss-of-function, dominant-negative and associated with impaired, but not abolished, TRAF3-dependent responses upon stimulation of both TNF receptors and receptors that induce IFN production. TRAF3 deficiency is associated with a clinical phenotype limited to HSE resulting from the impairment of TLR3-dependent induction of IFN. Thus, TLR3-mediated immunity against primary infection by HSV-1 in the central nervous system is critically dependent on TRAF3.

Infant feeding practices and sleep development in pre-schoolers from the EDEN mother-child cohort.

Sleep problems affect 20%-30% of toddlers and preschoolers. Few longitudinal studies focused on the impact of infant feeding practices on sleep. We aimed to study the associations between feeding practices up to 8 months and trajectories of sleep quantity or quality from 2 to 5-6 years. Analyses included 1,028 children from the EDEN mother-child cohort. Data were collected by self-administered questionnaires. Associations between feeding practices (breastfeeding, complementary feeding, use of thickened infant formula, night feeding) and sleep trajectories (sleep-onset difficulties, night waking, nighttime in bed) were analysed by multiple logistic regressions. Predominant breastfeeding for more than 4 months was associated with lower risk for belonging to the persistent sleep-onset difficulties trajectory. Night feeding at 4 months or at 2 years old was associated with higher risk for belonging to the persistent sleep-onset difficulties trajectory, and night feeding at 8 months was associated with higher risk for night waking and higher risk for short nighttime in bed. Early introduction (< 4 months) to complementary foods (excluding baby cereals) was related to lower risk for short nighttime in bed. Use of baby cereals or thickened infant formula was related neither to sleep quality nor to sleep quantity. In conclusion, infant feeding practices are associated with sleep trajectories in preschoolers, with notably a potential protective role of breastfeeding. Further researches are needed to clarify the mechanisms of these relationships.

Circadian nutritional behaviours and cancer risk: New insights from the NutriNet-santé prospective cohort study: Disclaimers.

Circadian disruption has been classified as probably carcinogenic to humans by the World Health Organization's International Agency for Research on Cancer. The circadian clock is subject to environmental factors, particularly light exposure and food intake rhythms. However, the association between nutritional circadian behaviours and cancer is not well understood. We investigated the longitudinal associations between number of eating episodes, night-time fasting duration, time of first and last eating episodes, as well as nutritional quality of last eating episode, respectively, with breast and prostate cancer risks, the two main cancer locations in women and men respectively. This prospective study included 41,389 day-working adults in the French NutriNet-Santé cohort (2009-2016) who completed at least three 24 h dietary records during the first 2 years of follow-up. Multivariable Cox models were computed. 1,732 first primary incident cancer cases were diagnosed during the follow-up, among which 428 breast and 179 prostate cancers. After adjustment for covariates including sleep duration, late eaters (last eating episode after 9:30 pm) had an increased risk of breast (Hazard ratio [HR] = 1.48 [1.02-2.17], p = 0.03) and prostate (HR = 2.20 [1.28-3.78], p = 0.004) cancers. However, no association was observed between cancer risk and number of eating episodes, night-time fasting duration, time of first eating episode or macronutrient composition of the last eating episode. This large cohort study suggests that circadian perturbations resulting from late time of last food intake may be involved in carcinogenesis at different locations. Beyond nutritional quality of food intake, nutritional circadian regulation should be further investigated in the context of cancer prevention.

Sleep and its relation to cognition and behaviour in preschool-aged children of the general population: a systematic review.

This is the first systematic review of the literature on sleep and its relation to cognition and behaviour in preschool-aged children. In comparison with the literature focused on school-aged children, knowledge involving preschoolers is rather sparse. A total of 26 studies was included in this review, which revealed a high degree of heterogeneity regarding the type and means of measuring sleep variables and behavioural and cognitive variables, as well as the statistical methods employed. Amongst the 13 articles with the largest sample sizes (top 50% of the included studies, 12 different populations), 12 found that a higher quantity or quality of sleep was associated with better behavioural and/or cognitive outcomes. Results point to an association between sleep, behaviour and cognition as early as preschool years, but the strengths of associations reported in the articles were relatively small. Studies with a smaller sample size were less concordant. It is consistent with our findings that the strengths of association are small, and thus require large sample sizes to ensure statistical detection power. Different aspects of sleep were not associated with all cognitive or behavioural features in the same way, which underscores the need for specific measures rather than general ones such as 'sleep problems' or 'behaviour problems' to be able to decipher the relationships. There is also a need for large longitudinal studies using objective measures and accounting for confounding factors. The child's genotype has recently been shown to have a moderating role in the association between sleep and behaviour, and should be further explored.

Impaired intrinsic immunity to HSV-1 in human iPSC-derived TLR3-deficient CNS cells.

In the course of primary infection with herpes simplex virus 1 (HSV-1), children with inborn errors of toll-like receptor 3 (TLR3) immunity are prone to HSV-1 encephalitis (HSE). We tested the hypothesis that the pathogenesis of HSE involves non-haematopoietic CNS-resident cells. We derived induced pluripotent stem cells (iPSCs) from the dermal fibroblasts of TLR3- and UNC-93B-deficient patients and from controls. These iPSCs were differentiated into highly purified populations of neural stem cells (NSCs), neurons, astrocytes and oligodendrocytes. The induction of interferon-ß (IFN-ß) and/or IFN-λ1 in response to stimulation by the dsRNA analogue polyinosinic:polycytidylic acid (poly(I:C)) was dependent on TLR3 and UNC-93B in all cells tested. However, the induction of IFN-ß and IFN-λ1 in response to HSV-1 infection was impaired selectively in UNC-93B-deficient neurons and oligodendrocytes. These cells were also much more susceptible to HSV-1 infection than control cells, whereas UNC-93B-deficient NSCs and astrocytes were not. TLR3-deficient neurons were also found to be susceptible to HSV-1 infection. The rescue of UNC-93B- and TLR3-deficient cells with the corresponding wild-type allele showed that the genetic defect was the cause of the poly(I:C) and HSV-1 phenotypes. The viral infection phenotype was rescued further by treatment with exogenous IFN-α or IFN-ß ( IFN-α/ß) but not IFN-λ1. Thus, impaired TLR3- and UNC-93B-dependent IFN-α/ß intrinsic immunity to HSV-1 in the CNS, in neurons and oligodendrocytes in particular, may underlie the pathogenesis of HSE in children with TLR3-pathway deficiencies.

Sleep Trajectories Among Pregnant Women and the Impact on Outcomes: A Population-Based Cohort Study.

Objectives Sleep problems and deprivation are common during pregnancy, particularly in the third trimester. Previous studies are mostly descriptive or focused on specific clinical groups and late pregnancy. We aimed to identify sleep duration trajectories during the pregnancy period, their associated factors, and impact on pregnancy and birth outcomes. Methods We studied 200 women from a mother-child cohort recruited in 2009-2011 from the French general population. We used semi-parametric models to analyze data collected through questionnaires. Results We detected three sleep duration trajectories during pregnancy: short-decreasing (<6.5h/night, 10.8% of the sample), medium-decreasing (6.5-8h/night, 57.6%), and long-increasing (>8h/night, 31.6%) trajectories. Factors associated with the short-decreasing trajectory relative to the medium-decreasing trajectory were older age (odds-ratio/year = 1.13 [95%Confidence-Interval 1.00-1.29]) and working > 28 weeks of gestational age (odds-ratio = 0.30 [0.10-0.90]). Sleep duration during pregnancy in this trajectory group was modified by insomniac symptoms (regression coefficient/trimester = -0.74 [Standard-Error 0.12]) and naps (regression coefficient/trimester = 0.58 [0.25]). Restless legs syndrome was the only factor associated with the long-increasing trajectory and decreased sleep duration (regression coefficient/trimester = -0.88 [0.25]). Assisted delivery (i.e. cesarean section and/or instrumental delivery) and post-partum depression were more frequent among women with the short-decreasing and long-increasing trajectories whereas cesarean section alone was more prevalent among those with the short-decreasing trajectory. Proportion of premature births was higher in the short-decreasing trajectory group. Birth-weight-z-score was lower in the long-increasing trajectory group. Conclusion We identified sleep trajectories among pregnant women with specific risk factors that could affect both pregnancy and birth outcomes. Taking these into consideration could improve both maternal and child health.

Gender-specific factors associated with shorter sleep duration at age 3 years.

Total sleep duration has been decreasing among children in the last decades. Short sleep duration (SSD) has been associated with deleterious health consequences, such as excess weight/obesity. Risk factors for SSD have already been studied among school-aged children and adolescents, but inconsistent results have been reported regarding possible gender differences. Studies reporting such relationships are scarce in preschoolers, despite the importance of this period for adopting healthy behaviour. We aimed to investigate factors associated with SSD in 3-year-old boys (n = 546) and girls (n = 482) in a French Mother-Child Cohort (EDEN Study). Children were born between 2003 and 2006 in two French university hospitals. Clinical examinations and parent self-reported questionnaires allowed us to collect sociodemographic (e.g. income, education, family situation, child-minding system), maternal [e.g. body mass index (BMI), parity, depression, breastfeeding duration] and child's characteristics (e.g. gender, birth weight, term, physical activity and TV viewing duration, food consumption, usual sleep time). Sleep duration/24-h period was calculated and SSD was defined as <12 h. Analyses were performed using logistic regression. The mean sleep duration was 12 h 35 ± 56 min, with 91% of the children napping. Patterns of risk factors associated with SSD differed according to gender. In addition to parental presence when falling asleep, short sleep duration was associated strongly positively with high BMI Z-score and TV viewing duration among boys and with familial home child-minding and lower scores on the 'fruits and vegetables' dietary pattern among girls. These results suggest either a patterning of parental behaviours that differs according to gender, or a gender-specific sleep physiology, or both.

Multidimensionality of the relationship between social status and dietary patterns in early childhood: longitudinal results from the French EDEN mother-child cohort.

BACKGROUND: The association between socioeconomic position and diet in early childhood has mainly been addressed based on maternal education and household income. We aimed to assess the influence of a variety of social factors from different socio-ecological levels (parents, household and child-care) on multi-time point dietary patterns identified from 2 to 5 y. METHOD: This study included 974 children from the French EDEN mother-child cohort. Two multi-time point dietary patterns were derived in a previous study: they correspond to consistent exposures to either core- or non-core foods across 2, 3 and 5 y and were labelled "Guidelines" and "Processed, fast-foods". The associations of various social factors collected during pregnancy (age, education level) or at 2-y follow-up (mother's single status, occupation, work commitments, household financial disadvantage, presence of older siblings and child-care arrangements) with each of the two dietary patterns, were assessed by multivariable linear regression analysis. RESULTS: The adherence to a diet close to "Guidelines" was positively and independently associated with both maternal and paternal education levels. The adherence to a diet consistently composed of processed and fast-foods was essentially linked with maternal variables (younger age and lower education level), household financial disadvantage, the presence of older sibling (s) and being cared for at home by someone other than the mother. CONCLUSIONS: Multiple social factors operating at different levels (parents, household, and child-care) were found to be associated with the diet of young children. Different independent predictors were found for each of the two longitudinal dietary patterns, suggesting distinct pathways of influence. Our findings further suggest that interventions promoting healthier dietary choices for young children should involve both parents and take into account not only household financial disadvantage but also maternal age, family size and options for child-care.

Parents' Sleep Multi-Trajectory Modelling from 3 to 36 Months Postpartum in the SEPAGES Cohort.

Objective: We investigated maternal and paternal sleep evolution from 3 to 36 months postpartum, their interrelations and predictors in the SEPAGES cohort. Methods: Sleep information (night sleep duration [NSD], weekend daytime sleep duration [DSD] and subjective sleep loss [SSL]) was collected by self-administered questionnaires at 3, 18, 24 and 36 months postpartum in the SEPAGES French cohort that included 484 mothers and 410 fathers. Group-based multi-trajectory modelling was used to identify maternal, paternal and couple sleep multi-trajectory groups among 188 couples reporting sleep data for at least 2 time points. Multinomial logistic regression was used to assess associations between parental sleep multi-trajectories and early characteristics such as sociodemographic, chronotypes, child sex, birth seasonality or breastfeeding duration. Results: We identified three maternal (M1-M3), paternal (F1-F3) and couple (C1-C3) sleep multi-trajectory groups with similar characteristics: a group with short NSD and high SSL prevalence (M1, F2, C2), a group with long NSD but medium SSL prevalence (M2, F3, C3) and a group with long NSD and low SSL prevalence (M3, F1, C1). Mothers with the shortest NSD (M1) were less likely to have a partner with long NSD (F2). As compared with long NSD and low SSL prevalence (C1), couples with short NSD and high SSL prevalence (C2) were less likely to have had a first child born in the autumn and fathers in C2 had a later chronotype. Conclusion: We identified distinct sleep multi-trajectory groups for mothers, fathers and couples from 3- to 36-month postpartum. Sleep patterns within couples were homogeneous.

Does the brain sleep differently depending on intellectual abilities?

AIMS: To compare the children's sleep electroencephalogram according to their intellectual profile. METHODS: Children were grouped according to their Wechsler Intelligence Scale for Children (WISC) scores (17 with normal intelligence quotient [IQ, NIQ] and 24 with high IQ [HIQ]). Comparisons of spectral power between groups and its relationship with WISC scores were assessed using analyses of variance and linear regression models, adjusted for age and sex. RESULTS: Children with HIQ had more rapid eye movement (REM) sleep, especially late at night, and more power in slow-frequency bands during REM sleep than those with NIQ. There were also positive associations between the processing speed index and the spectral power in ß bands in NREM sleep, and with the spectral power in α, σ, ß, and γ bands in REM sleep, with different associations between groups. CONCLUSION: The enhanced power in slow bands during REM sleep in children with HIQ overlaps with that of typical REM sleep oscillations thought to be involved in emotional memory consolidation. The dissimilar relationships between spectral power and WISC scores in NIQ and HIQ groups may underlie functional differences in brain activity related to cognitive efficiency, questioning the direction of the relationship between sleep and cognitive functioning.

Why circadian rhythmicity matters: Associations between sleep irregularity and mental health conditions during the Covid-19 health crisis.

OBJECTIVE: To assess the association between sleep irregularity, anxiety, and depression while controlling for other sleep dimensions and using a longitudinal design. METHODS: Longitudinal cohort study which started in April 2020 during the first French lockdown in the general population. Follow-up questionnaires were completed in June 2020, a period without lockdown measures. Participants were asked about their sleep (regularity, duration, timing, complaints) and their anxiety (General Anxiety Disorder-7) and depressive (Patient Health Questionnaire-9) symptoms. RESULTS: A total of 3745 participants were included (mean age: 28.9 years) with 2945 women (78.6%). At baseline, 38.1% (1428) of participants reported irregular sleep timing, 23.8% (891) anxiety and 28.9% (1081) depressive symptoms. In cross-sectional analyses, irregular sleep timing was associated with a 2.5-fold higher likelihood of anxiety and a 4-fold higher likelihood of depressive symptoms compared to regular sleepers. Associations were not explained by the other sleep dimensions and persisted in a longitudinal analysis, with irregular sleep timing at baseline being associated with anxiety (OR = 3.27[1.58-6.76]) and depressive symptoms (OR = 3.45[1.66-7.19]) during follow-up. CONCLUSION: The results show a strong association between sleep irregularity and mental health. Furthers studies are needed to explore how sleep regularity could promote good mental health in non-clinical populations.

Effectiveness of an intervention program on physical activity in children with narcolepsy type 1.

OBJECTIVES: Physical activity (PA) is recommended as part of the management of narcolepsy type 1 (NT1). This study aimed at 1) characterizing PA in children and adolescents treated for NT1 using objective and subjective measurements, 2) evaluating how PA is associated with NT1 symptoms and comorbidities, and 3) evaluating the effects of an Adapted Physical Activity (APA) program on PA and clinical characteristics. PATIENTS/METHODS: Patients with NT1 from the National Reference Center of Narcolepsy (Lyon, France) were consecutively included in an APA intervention protocol. Narcolepsy symptoms and comorbidities were collected using standardized questionnaires and sustained attention was evaluated using the Bron-Lyon Attention Stability Test before and after the four-week APA intervention. PA was measured objectively using actigraphy throughout the study. RESULTS: Twenty-seven NT1 patients were included (median age 14.7 years [8.3-18.4], cataplexy 88.9%, obesity 37.0%). At baseline, 52.4% of the patients had satisfactory PA levels according to international recommendations. Patients with leisure-time PA (LTPA) showed higher quality of life than patients without. 45% of the patients increased PA during the intervention compared to baseline. These responsive patients had more depressive feelings and tended to have lower objective PA than non-responsive patients at baseline. No significant correlation was found between PA levels before and during the intervention and other clinical data. CONCLUSIONS: Most children with NT1 showed satisfying PA levels despite their daytime sleepiness. LTPA engagement was associated with higher quality of life. An APA intervention could be effective in children with narcolepsy, especially for those with depressive feelings.

Study of the association between cannabis use and sleep disturbances in a large sample of University students.

Sleep complaints and cannabis use are common among University students and are related to detrimental effects on health. The aim of this study was to explore their association. This cross-sectional study based on the i-Share e-cohort included French students between 18 and 30 years old (n = 14,787). Frequency of cannabis use was categorized into daily, weekly, monthly, and never/rarely use. Sleep complaints were defined using four items (i.e., insomnia, sleepiness, poor sleep quality, and sleep deprivation). In the whole sample (mean age: 20.4 years, 75.5% of females), 22.7% had insomnia, 18.3% had sleepiness, 22.4% had poor sleep quality, 52.5% had sleep deprivation, and 5.8% used cannabis weekly or daily. After adjustment, the likelihood of insomnia was significantly higher by 45% in cannabis users compared to non-users. The estimates steadily increased with frequency of use, reaching a 2.0-fold higher likelihood of insomnia in daily users compared to never/rarely users. Results were similar for the other sleep complaints. These findings provide support for an association between cannabis use and sleep complaints, particularly insomnia, among University students. Though direction and causality cannot be established in this setting, these results suggest warning students and health professionals about the association between cannabis use and sleep complaints.