To sleep or to breastfeed: Associations between feeding method and sleep in infants and children.

AIM: This study aimed to understand the association between feeding method, specifically breastfeeding versus non-breastfeeding, at 6 and 12 months and infant sleep over the first 3 years of life. METHODS: A sample of 444 mother-infant dyads from the Maternal Adversity, Vulnerability and Neurodevelopment cohort were analysed. Based on retrospective maternal reports between 3-24 months, infants' breastfeeding status was determined at 6 and 12 months. Nocturnal sleep duration, longest period of consecutive sleep, and total sleep over 24 h were measured by maternal reports at 6, 12, 24 and 36 months. RESULTS: Generalized Estimating Equations revealed no significant association between feeding status, both at 6 and 12 months, and nocturnal sleep duration or total sleep over 24 h between 6-36 months (p > 0.05). However, breastfeeding at both 6 and 12 months was associated with shorter periods of consecutive sleep, at 6 and 12 months (p < 0.05) but not at 24 and 36 months (p > 0.05). CONCLUSION: Our findings suggest that breastfeeding seems to be associated with more infant sleep fragmentation but not with total sleep duration in early infancy. However, this sleep fragmentation does not persist into later infancy and early toddlerhood.

Sleep patterns and intraindividual sleep variability in mothers and fathers at 6 months postpartum: a population-based, cross-sectional study.

OBJECTIVES: Given that postpartum sleep is an important family process, further investigations including both mothers and fathers are necessary. The present study aimed to describe and compare sleep patterns and intraindividual night-to-night variability in mothers and fathers at 6 months postpartum using subjective and objective sleep measures. DESIGN: Cross-sectional study. SETTING: General community-based study in Montreal, QC, Canada. PARTICIPANTS: Thirty-three couples (mothers and fathers) with no self-reported history of medical and mental health conditions participated in this study. RESULTS: Parental sleep was measured across 10 consecutive nights using both a daily sleep diary and actigraphy. Results demonstrated that mothers' subjective and objective sleep was more fragmented compared with fathers (shorter longest consecutive sleep duration and more nocturnal awakenings; p<0.001). While mothers and fathers did not differ in their self-reported nocturnal sleep duration (p>0.05), actigraphy indicated that mothers obtained significantly longer nocturnal sleep duration (448.07 min±36.49 min) than fathers (400.96 min±45.42 min; p<0.001). Intraindividual sleep variability was revealed by relatively high coefficients of variation for parents across both subjective and objective indices related to sleep fragmentation (between 0.25 and 1.32). Actigraphy also demonstrated variability by mothers sleeping 6 hours consecutively on less than 3 nights, 27.27% (±22.81), and fathers on less than 6 nights, 57.27% (±24.53), out of 10. Associations were also found between parental sleep and family factors, such as age and infant sleep location (p<0.05). CONCLUSIONS: These findings advance our knowledge of how sleep unfolds within the family system beyond the early postpartum weeks and/or months. Given the link between disturbed sleep and family functioning, the current research accentuates the importance of examining postpartum sleep patterns and variability in parents.

Sleep terrors in early childhood and associated emotional-behavioral problems.

STUDY OBJECTIVES: While sleep terrors are associated with emotional-behavioral problems in school-aged children and adults, little is known about these associations in early childhood, when sleep terrors prevalence is at its highest. Moreover, studies using a longitudinal design and controlling for confounding variables are scarce. This study's objective was to determine whether the frequency of sleep terrors in toddlers predicts emotional-behavioral problems during the preschool years. METHODS: Participants (n = 324) were enrolled in the prospective Maternal Adversity Vulnerability and Neurodevelopment cohort study. The frequency of sleep terrors in children was assessed at 12, 18, 24, and 36 months using maternal reports. Children's emotional-behavioral problems were measured at 48 and 60 months using the Child Behavior Checklist. Relevant confounders linked to the child, mother, and environment were also taken into consideration. RESULTS: The frequency of sleep terrors was relatively stable across early childhood (16.7-20.5%). A generalized estimating equation revealed that the frequency of sleep terrors in early childhood was associated with increased emotional-behavioral problems at 4 and 5 years of age, more specifically with internalizing problems (P < .001), after controlling for child's sex, time point, family socioeconomic status, maternal depressive symptoms, and nighttime sleep duration. The frequency of sleep terrors was further associated with the emotionally reactive, anxious/depressed, and somatic complaints scales (P < .01). CONCLUSIONS: This longitudinal study provides further support for a high prevalence of sleep terrors in early childhood. Our findings show meaningful associations between higher frequency of sleep terrors and emotional-behavioral problems as early as toddlerhood, especially internalizing problems. CITATION: Laganière C, Gaudreau H, Pokhvisneva I, et al. Sleep terrors in early childhood and associated emotional-behavioral problems. J Clin Sleep Med. 2022;18(9):2253-2260.

Investigating the link between sleep and postpartum depression in fathers utilizing subjective and objective sleep measures.

BACKGROUND: While fathers are at risk of developing poorer sleep and depressive symptoms in the postpartum period, they represent an understudied population in the literature. The present study aimed to explore the association between sleep and postpartum depressive symptoms in fathers using subjective and objective sleep measures. METHODS: Fifty-four fathers reporting no history of depression took part in this cross-sectional study. At 6 months postpartum, paternal sleep was assessed for 2 weeks utilizing a self-report daily sleep diary, a self-report perceived sleep quality rating, and actigraphy. In the same period, depressive symptoms in fathers were assessed with the Center for Epidemiologic Studies-Depression Scale (CES-D). RESULTS: Regression analyses showed that paternal subjective sleep variables captured by the sleep diary (total nocturnal sleep time and number of night awakenings) were not related to postpartum depressive symptoms. However, self-reported perceived sleep quality was significantly associated with postpartum depressive symptom severity in fathers independently of demographic variables related to depression. Alternatively, the objective sleep variables (total nocturnal sleep time, number of night awakenings, sleep efficiency, and wake after sleep onset), measured by actigraphy, did not demonstrate a significant relationship with paternal depression scores. CONCLUSIONS: These findings highlight the importance of perceived sleep quality, along with better understanding its association with postpartum depressive symptoms. Implementing a multi-measure approach enabled us to expand our knowledge about how different facets of sleep relate to postpartum depression, specifically in fathers. The results have important implications for the development of clinical interventions targeting paternal sleep and mood in the postpartum period.

Video-Polysomnographic Assessment for the Diagnosis of Disorders of Arousal in Children.

OBJECTIVES: To highlight the slow-wave sleep (SWS) fragmentation and validate the video-polysomnographic (vPSG) criteria and cutoffs for the diagnosis of disorders of arousal (DOA) in children, as already reported in adults. METHODS: One hundred children (66 boys, 11.0 ± 3.3 years) with frequent episodes of DOA and 50 nonparasomniac children (32 boys, 10.9 ± 3.9 years) underwent vPSG recording to quantify SWS characteristics (number of N3 sleep interruptions, fragmentation index, slow/mixed and fast arousal ratios, and indexes per hour) and associated behaviors. We compared SWS characteristics in the 2 groups and defined the optimal cutoff values for the diagnosis of DOA using receiver operating characteristic curves. RESULTS: Patients with DOA had higher amounts of N3 and REM sleep, number of N3 interruptions, SWS fragmentation, and slow/mixed arousal indexes than controls. The highest area under the curve (AUC) values were obtained for SWS fragmentation and slow/mixed arousal indexes with satisfactory classification performances (AUC 0.80, 95% confidence interval [CI] 0.73-0.87; AUC 0.82, 95% CI 0.75-0.89). SWS fragmentation index cutoff value of 4.1/h reached a sensitivity of 65.0% and a specificity of 84.0%. Slow/mixed arousal index cutoff of 3.8/h reached a sensitivity of 69.0% and a specificity of 82.0%. At least one parasomniac episode was recorded in 63.0% of patients and none of the controls. Combining behavioral component by vPSG increased sensitivity of both biomarkers to 83% and 89%, respectively. CONCLUSIONS: We confirmed that SWS fragmentation and slow/mixed arousal indexes are 2 relevant biomarkers for the diagnosis of DOA in children, with different cutoffs obtained than those validated in adults. CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that SWS fragmentation and slow/mixed arousal indexes on vPSG accurately identify children with DOA.

Disturbed nighttime sleep in children and adults with rhythmic movement disorder.

STUDY OBJECTIVES: Rhythmic movements (RMs) during sleep are frequent and often considered as benign in children. Disabling forms are diagnosed as RM disorder and may persist in adulthood. Whether RMs severely impact sleep architecture in patients with RM disorder remain unclear. We performed a case-control study to characterize the clinical and polysomnographic patterns of children and adults with a diagnosis of RM disorder in comparison to controls, and to assess the associations between the RMs and the sleep architecture. METHODS: All consecutive patients (n = 50; 27 children, 35 males) with RM disorder from a single sleep clinic (from 2006 to 2019) underwent a comprehensive clinical evaluation and a polysomnographic recording in comparison to 75 controls (42 children and 53 males). RESULTS: About 82% of children and adult patients had a complaint of disturbed nighttime sleep. Comorbid neurodevelopmental, affective or sleep disorders were found in 92% of patients. While RM sequences defined by video polysomnographic criteria were observed in 82% of patients (in wakefulness and in all sleep stages), no similar sequences were observed in controls. Patients had altered sleep continuity, with low sleep efficiency, increased wake time after sleep onset, and frequent periodic leg movements and apnea events. The severity of RMs was associated with disrupted nighttime sleep, even after controlling for comorbid motor and respiratory events. CONCLUSIONS: RM disorder is a rare, highly comorbid and disabling condition both in children and adults with frequent disturbed nighttime sleep that may contribute to the burden of the disease.

Maternal characteristics and behavioural/emotional problems in preschoolers: how they relate to sleep rhythmic movements at sleep onset.

Sleep rhythmic movements have been speculated to be a form of self-soothing. While this sleep-related movement has been associated with lower socioeconomic status, psychopathologies and maternal characteristics, prospective studies with sizeable sample and objective measurements are lacking. The objectives were: (a) to identify maternal characteristics predicting sleep rhythmic movements in children; and (b) to document behavioural/emotional problems in preschoolers with sleep rhythmic movements. Participants were mother-child dyads (N = 529) from the Adversity: Maternal Adversity, Vulnerability and Neurodevelopment cohort. Questionnaires evaluating socioeconomic status (prenatal), maternal depressive symptoms (prenatal, 48 months), sleep rhythmic movements (12, 18, 24, 36, 48 months), maternal anxiety trait (24 months) and children's behavioural/emotional problems (48 months) were used. Maternal sensitivity (accuracy and appropriateness of mother's responses to her baby's needs) was assessed objectively with a filmed mother-infant interaction (6 months). Generalized estimating equation was used to investigate associations between sleep rhythmic movements and maternal characteristics (depression, anxiety and sensitivity). Linear regressions were used to assess associations between sleep rhythmic movements and behavioural/emotional problems in children. Lower maternal sensitivity, higher maternal depressive symptoms and lower socioeconomic status predicted sleep rhythmic movements in children (p < 0.05). To our knowledge, this is the first study showing that sleep rhythmic movements are associated with lower maternal sensitivity, measured objectively. This study also builds on previous reports, by documenting an association between sleep rhythmic movements and behavioural/emotional problems even in preschoolers. The presence of psychosocial factors in sleep rhythmic movements aetiology should be considered in treatment.

Uninterrupted Infant Sleep, Development, and Maternal Mood.

OBJECTIVES: Contrary to the importance of total sleep duration, the association between sleeping through the night and development in early infancy remains unclear. Our aims were to investigate the proportion of infants who sleep through the night (6- or 8-hour sleep blocks) at ages 6 and 12 months in a longitudinal cohort and to explore associations between sleeping through the night, mental and psychomotor development, maternal mood, and breastfeeding. METHODS: At 6 and 12 months of age, maternal reports were used to assess the longest period of uninterrupted infant sleep and feeding method (n = 388). Two different criteria were used to determine if infants slept through the night: 6 and 8 hours of uninterrupted sleep. Mental and psychomotor developmental indices (Bayley Scales of Infant Development II) and maternal mood (Center for Epidemiologic Studies Depression Scale) were measured at 6, 12, and 36 months of age. RESULTS: Using a definition of either 6 or 8 hours of uninterrupted sleep, we found that 27.9% to 57.0% of 6- and 12-month-old infants did not sleep through the night. Linear regressions revealed no significant associations between sleeping through the night and concurrent or later mental development, psychomotor development, or maternal mood (P > .05). However, sleeping through the night was associated with a much lower rate of breastfeeding (P < .0001). CONCLUSIONS: Considering that high proportions of infants did not sleep through the night and that no associations were found between uninterrupted sleep, mental or psychomotor development, and maternal mood, expectations for early sleep consolidation could be moderated.