Predictors of sleep disturbances in the first year of life: a longitudinal study

Sleep characteristics and changes in sleep patterns among infants in Bhaktapur, Nepal

OBJECTIVE

Sleep undergoes major changes during the first year of life, but the characteristics of sleep among infants in low and middle-income countries are not well documented. This study describes sleep characteristics and changes in sleep patterns in infants at 6 and 12months of age from Bhaktapur, Nepal.

METHODS

This was a community-based longitudinal study comprising 735 infants. Sleep characteristics were obtained by interview with the mother using the Brief Infant Sleep Questionnaires. The stability of sleep duration and night awakenings were estimated by logistic regression analysis.

RESULTS

Cosleeping in the parent's bed at 6 and 12months of age was almost universal (>97%). At 6months of age, 254 (35%) and at 12months of age, 341 (46%) infants had a total 24-hour sleep duration <12 hours. Night awakenings >3 times per night were common (65%) both at 6 and 12months of age. Infants with frequent nightly awakenings at 6months had increased odds of frequent nightly awakenings at 12months (OR=2.2; 95% CI: 1.6, 2.9). Very few (<3%) mothers reported sleep problems in their infants at 6 and 12months of age.

CONCLUSIONS

Cosleeping was almost universal among Nepalese infants, and very few of the mothers reported sleep problems in their infants. Infants at 6 and 12months had similar patterns for both sleep duration and nocturnal awakenings. For infants, there were increased odds of having similar sleep duration and nocturnal awakening at 6 and 12months.

Study on Nocturnal Infant Crying Evaluation (NICE) and Reflux Disease (RED)

BACKGROUND

Nocturnal infant crying is often empirically treated with acid suppressants. The aim of this study was to evaluate the prevalence and characteristics of gastroesophageal reflux (GER) in infants with unexplained persistent crying.

METHODS

We enrolled all infants (0-12 months) referred for suspected GER disease who underwent esophageal impedance-pH monitoring (MII-pH) for unexplained persistent crying not improved by parental reassurance, dietary modification or alginate. Gastrointestinal malformation/surgery, neurological impairment and infections were exclusion criteria. Demographic and anthropometric parameters, GER symptoms and questionnaires (I-GERQ-R) and MII-pH data were recorded and analyzed. Normal MII-pH was defined when acid exposure was <3%, symptom index was <50% and symptom association probability was <95%. Acid exposure >5% and >10% was also considered. Statistical analysis was performed using Chi-Square and univariate and multivariable regression analysis.

RESULTS

We included 50 infants (median age 3.5 months) who fulfilled the study criteria: 30 (60%) had normal MII-pH. I-GERQ-R score was abnormal in 33 (66%) infants, and 21/33 (64%) had normal MII-pH (p = 0.47). In the 26 (52%) infants with nocturnal crying, MII-pH was normal in 16 (54%) (p = 0.82). Associated regurgitation (>3 or >10 episodes/die) did not predict abnormal MII-pH (p = 0.74, p = 0.82, respectively). Univariate and multivariable regression analysis did not identify any clinical variable significantly associated with abnormal MII-pH.

CONCLUSIONS

Infants with persistent unexplained and nocturnal crying should not be empirically treated with acid inhibitors.

Sleep characteristics, early spontaneous movements, and developmental functioning in preterm infants in the early postnatal period

OBJECTIVE

This study aimed to investigate the following: (i) sleep characteristics in preterm infants at 9-20 weeks of corrected age, and (ii) differences in early spontaneous movements and developmental functioning results between the groups based on some sleep characteristics.

METHODS

Seventy-four preterm infants (36 female) were included. Sleep characteristics were assessed according to the Brief Infant Sleep Questionnaire (BISQ). The infants were divided into two groups based on total sleep duration: less than 12 h (38 infants), and 12 h and more (36 infants). Video recordings were made for the General Movements Assessment (GMA) and evaluated using the Motor Optimality Score for 3- to 5-Month-Old-Infants-Revised (MOS). Cognitive, language, and motor development were assessed using the Bayley Scales of Infant and Toddler Development, Third Edition (Bayley-III).

RESULTS

The total sleep duration of all preterm infants (mean ± SD) was 11.8 ± 3.3 h. Infants who had absent fidgety movements slept less than 12 h, and fidgety movements differed between the groups (p = 0.012). Infants who slept 12 h or more had significantly higher MOS (p = 0.041), cognitive (p = 0.002), language (p < 0.001), and motor (p = 0.002) development results. Infants who snored had lower MOS (p = 0.001), cognitive (p = 0.004), language (p = 0.002), and motor (p = 0.001) development results. Infants with fewer than three nocturnal awakenings had significantly higher Bayley-III cognitive (p = 0.007), language (p = 0.032), and motor (p = 0.005) domain results. Prone and supine sleeping positions showed higher motor domain results than lateral positions (p = 0.001).

CONCLUSIONS

Sleep in preterm infants might be a key factor in early developmental functioning processes and nervous system integrity. Even in the first months of life, there are substantial differences in cognitive, language, and motor development in association with sleep characteristics.

Maternal Circadian Disruption from Shift Work and the Impact on the Concentration of Melatonin in Breast Milk

Background and Objective: Melatonin in breast milk exhibits a 24-hour circadian rhythm, present in nighttime breast milk but nearly undetectable in daytime breast milk. Shift work can disrupt the circadian timing of individuals, evident in changes in melatonin in saliva and urine samples. However, it is unknown whether these changes are also reflected in breast milk from a shift working mother. The aim of this study was to investigate whether maternal circadian rhythm disturbance from shift work impacts the melatonin concentration in breast milk. Materials and Methods: Breast milk and saliva samples were collected from 11 shift working mothers at four timepoints across five consecutive days. This included during their day shift or nonworkdays to act as a control, night shift, subsequent night shifts and postnight shift. Where possible, pre- and postfeed collections were also undertaken. Samples were grouped into four-time intervals: 12-6:30 am, 7-11:30 am, 12-6:30 pm, 7-11:30 pm, and melatonin levels (picogram per milliliter) in the breast milk and saliva samples were analyzed. Results: There was a significant decrease in breast milk melatonin (p = 0.026) at the 12-6:30 am time interval on subsequent night shifts, compared with control days. However, there was no overall time and shift type interaction effect (p = 0.70). In addition, no observed difference in melatonin levels was found in saliva samples, or when comparing pre- and postfeed breast milk. Breast milk melatonin however was found to be significantly higher compared with saliva (p > 0.001), at all but one time interval. Conclusion: The findings suggest that there is a potential effect of maternal circadian rhythm disruption from shift work on breast milk melatonin levels. This is an important step in exploring the role of maternal circadian timing and the effect on breast milk composition. Expansion of this research and exploration of other circadian rhythm misalignment sleep disorders on breast milk is highly recommended.

Sensory processing and sleep characteristics in preterm infants in the early period of life

OBJECTIVE

The present study aimed to investigate the following: (i) differences in sensory processing and sleep characteristics between preterm infants born at < 32 weeks', vs. those born at ≥ 32 weeks' gestation; (ii) differences in sleep characteristics between preterm infants with typical vs. atypical sensory processing; and (iii) relationship between sensory processing and sleep characteristics in preterm infants at 3 months of age.

METHODS

A total of 189 preterm infants, 54 born at < 32 weeks' gestation (26 females; mean gestational age [standard deviation (SD)], 30.1 [1.7] weeks), and 135 born at ≥ 32 weeks' gestation (78 females; mean gestational age [SD], 34.9 [0.9] weeks) were included in the present study. Sleep characteristics were evaluated using the Brief Infant Sleep Questionnaire, and sensory processing was assessed using the Infant Sensory Profile-2.

RESULTS

There were no significant differences in sensory processing (P > 0.05) or sleep characteristics (P > 0.05) between the preterm groups; however, more infants snored in the <32 weeks' gestation group (P = 0.035). Preterm infants with atypical sensory processing showed lower nighttime (P = 0.027) and total sleep durations (P = 0.032), and higher rates of nocturnal wakefulness (P = 0.038) and snoring (P = 0.001) than preterm infants with typical sensory processing. A significant relationship, therefore, was observed between sensory processing and sleep characteristics (P < 0.05).

CONCLUSIONS

Sensory processing patterns may play an important role in understanding sleep problems in preterm infants. The early detection of sleep problems and sensory processing difficulties are necessary for early intervention.

Breastfeeding and Maternal Perceptions of Infant Sleep, Settle and Cry Patterns in the First 9 Months

This study evaluated relationships between maternal perceptions of infant sleep, settling and crying patterns and breastfeeding. A prospective observational study of 91 mothers of healthy, term infants was conducted with follow ups over 9 months after discharge from a Western Australian maternity hospital. Feeding information, sleep, settle and cry behaviours, maternal bother at infant behaviours and confidence were measured using the Sleep and Settle Questionnaire. Breastfeeding confidence was measured using the Breastfeeding Self-Efficacy Scale-Short Form. Questionnaires were administered at 2 and 6 weeks, 3, 6 and 9 months. Linear mixed models were used to assess associations between maternal bother, feeding method and infant characteristics. The feeding method was not associated with maternal bother, and cessation of breastfeeding did not result in a change in bother scores (p = 0.34). Duration of infant crying in the day, evening and night, frequency of night waking and duration of settling to sleep in the day were associated with increased bother scores. Higher breastfeeding self-efficacy and maternal confidence were associated with lower bother scores (both p < 0.01). Maternal bother is associated with infant behaviours that require parental input, but not breastfeeding status. Resources that address parental expectations regarding infant sleep while providing strategies to support maternal wellbeing and breastfeeding are needed.

Preliminary Exploration into the Impact of Mistimed Expressed Breast Milk Feeding on Infant Sleep Outcomes, Compared to Other Feeding Patterns

Background and Objective: The presence and fluctuation of melatonin in breast milk during the night and day may be providing sleep timing information to infants, thereby supporting/enabling the development of their own circadian cycle. If this is the case, then it is important that infants consume breast milk according to the time of day it is produced. However, breast milk is not always consumed at the "right" time. The aim of this study was to investigate whether consuming mistimed expressed breast milk impacts infant sleep compared with other feeding types. Methods: A total of 329 mothers completed an online anonymous survey. Mothers were grouped into one of five groups; direct breastfed only, formula only, express mistimed, express-timed, and combined breastfed/formula fed. Results: Cross-sectional analysis showed mistimed expressed breast milk was significantly associated with delayed sleep onset of the infant (p < 0.001), but direct breastfed infants had significantly more awakenings at night (p < 0.001). Conclusions: The findings from this study suggest a potential effect of mistimed expressed breast milk consumption on an infant's circadian rhythm, affecting some aspects of their sleep. This is an important first step in exploring mistimed feeding on infant sleep outcomes and provides preliminary evidence that warrants future research.

Study protocol: assessing SleeP IN infants with early-onset atopic Dermatitis by Longitudinal Evaluation (The SPINDLE study)

BACKGROUND

Atopic dermatitis (AD) is the most common chronic inflammatory skin condition in childhood. Most (50-60%) children with AD report sleep disturbance, which is secondary to itch, dry skin, inflammation, and abnormal circadian rhythm. Sleep is essential for brain development, learning, and growth. Sleep disruption in early life is associated with cognitive and psychological dysfunction in later life. The aim of this study is to describe in detail the sleep architecture of infants with early-onset atopic dermatitis (AD), compared to controls, by using EEG polysomnography, sleep actigraphy, and parental reporting.

METHODS

This observational study will recruit six- to eight-month old infants with moderate to severe AD and age-matched control infants who do not have AD. At six-eight months diurnal sleep electroencephalography and polysomnography will be performed in our research center. Nocturnal sleep actigraphy will be performed at home for five consecutive nights at six-eight months and 12 months. Between six and 12 months, monthly questionnaires will capture data on quantitative sleep and parental sleep. Skin barrier and immune profiles will be captured at six-eight and 12 months. AD will be assessed using standardized severity assessment tools and treated according to protocol. A neurodevelopmental assessment will be performed at 18 months to assess cognition and behaviour. An estimated sample size of 50 participants in each group is required to power the primary outcome of disturbed macrostructure of sleep and secondary outcomes of disturbed microstructure of sleep, and disturbed parental sleep, assuming an attrition rate of 60%. Potential confounding factors which will be controlled for in the data analysis will include parental educational level, parental depression, feeding practice, and number of siblings.

DISCUSSION

This study will provide a rich analysis of sleep in infants with AD in the first year of life using detailed electroencephalography, novel actigraphy techniques, and longitudinal parent-reported data. It may provide guidance on the optimal treatment of AD to prevent or reduce sleep disruption.

TRIAL REGISTRATION

clinicaltrials.gov NCT05031754 , retrospectively registered on September 2nd, 2021.

Comparing infant and toddler sleep patterns prior to and during the first wave of home confinement due to COVID-19 in Spain

Recent literature has shown that sleep patterns are shaped during the first years of life, playing a relevant role in children's functioning. We focused on comparing sleep patterns in infants and toddlers in Spain before and during COVID-19 home confinement to assess the immediate impact on sleep patterns. We compared data from two cross-sectional surveys from parents of 1658 children three to 36 months of age from Spain. One conducted before COVID-19 (2017-2018, n = 1380) and another during COVID-19 pandemic (March-May of 2020, n = 254). We used an internet self-administrated questionnaire using the Brief Infant Sleep Questionnaire (BISQ) criteria in both surveys. During confinement, infants and toddlers went to sleep later (median bedtime 21:30 before confinement vs. 21:36 during confinement (p = 0.004)). More infants and toddlers showed longer sleep latencies (> 30 min) during confinement median 33.9% versus 12.3% (p < 0.001). Based on the recommended BISQ criteria, we observed an increase in poor sleepers meeting at least one criterion of inadequate patterns during confinement (p < 0.001). Parental perception of a child's sleep as problematics were 39.4% and 44.1% (adjusted p = 0.363) before and under lockdown, respectively.

CONCLUSION

Home confinement generally affected infant's and toddler's sleep patterns negatively; however, parents did not report worse perception of sleep quality of their children. Follow-up studies can help understand the potential long-term effects of the COVID-19 pandemic on sleep patterns.

WHAT IS KNOWN

• Adequate sleep patterns in infants and toddlers are relevant as they are linked to proper and long-term social-emotional development as well as adequate daytime functioning. • Regarding sleep patterns in paediatrics during the COVID pandemic, recent literature has described an increase in total daily sleep time as well as more exposure to screens in children and adolescents, providing evidence of immediate collateral consequences of the COVID-19 outbreak.

WHAT IS NEW

• Comparing sleep patterns in two samples of infants and toddlers in Spain before and during COVID-confinement, we found later bedtimes as well as a significant increase in infants' and toddlers' sleep latency by >30 min during confinement. • Parental self-reported questionnaire during COVID-19 home confinement reported an overall worsening of their children's sleep based on the BISQ criteria.

Sleep Characteristics in the Italian Pediatric Population: A Systematic Review

OBJECTIVE

During childhood sleep duration, quality and patterns evolve and change greatly and relate strongly to healthy development. This systematic review aims to summarize the literature on sleep characteristics in the Italian pediatric population, adopting a cultural perspective.

METHOD

Pubmed, PsycINFO and Medline databases were systematically searched. Eligible studies had to: include Italian children and adolescents; report data for one or more sleep-related variables; be published in English or Italian.

RESULTS

Twenty-nine studies were selected including 18551 Italian children or adolescents. Studies were categorized by age group: infancy and toddlerhood (0-3 years); preschool and school age (3-12 years); adolescence (12-18 years) and mixed age groups. Overall, studies showed that the Italian pediatric population present shorter sleep duration and longer sleep onset latency compared to international recommendations. Furthermore, data indicate high prevalence of dysfunctional sleep habits, such as late bed-time (all age groups), involvement of parents during bed-time (infancy and toddlerhood), and high variability between sleep times on week-days vs. weekends (adolescence). Nevertheless, most studies lacked comprehensive data on sleep patterns, focusing instead on isolated variables.

CONCLUSION

These results suggest a strong trend among Italian children and adolescents towards unhealthy sleep patterns. Comprehensive data are still lacking and large studies evaluating a broad range of sleep characteristics in Italian pediatric populations are needed. Data strongly suggest that Italian Pediatric Primary Care should place higher focus on sleep problems and implement clinical protocols directed towards improving sleep patterns in children and adolescents.

Unidirectional and bidirectional links between maternal depression symptoms and infant sleep problems

The present study explored (a) the unidirectional and bidirectional links between maternal depression symptoms and infant sleep problems and (b) the moderating role of the infant's sex on these unidirectional and bidirectional links. Mothers (N = 312) completed measures of depression symptoms at the third pregnancy trimester, and measures of depression symptoms and infant sleep problems at 2 weeks, and at 3 and 6 months postpartum. The findings revealed: (a) a main unidirectional link between maternal depression symptoms during the third trimester and infant sleep problems, particularly on infant unsettled sleep and daytime sleepiness at 3 and 6 months; (b) bidirectional links between maternal postpartum depression symptoms and infant unsettled sleep at 2 weeks, 3 and 6 months of life; and (c) the reported links between maternal depression symptoms and infant sleep problems occur specifically in boys and their mothers. Maternal prenatal depression symptoms are linked to infant sleep problems and infant sleep problems are linked to maternal postnatal depression symptoms. Boys are more susceptible to the effects of maternal prenatal and postnatal depression symptoms, and mothers of boys are more susceptible to the effects of boys' sleep problems.

How do infants and toddlers sleep in Spain? A cross-sectional study

There is limited information on sleep patterns among infants and toddlers in Spain. The aim of this study was to assess sleep patterns in children three to 36 months of age in Spain. A cross-sectional study was conducted between February 2017 and February 2018. Sociodemographic data and sleep variables were collected using an expanded version of the validated Spanish version of the brief infant sleep questionnaire. A total of 1,404 parental reports on children (725 males; 679 females) with a mean age of 18.8 ± 9.5 months were collected. Parents who perceived their child's sleep as problematic (39% of our sample) reported fewer sleep hours (median 9 versus 10 h), more night awakenings (median 2 versus 1), and longer periods of nocturnal awakenings (median 0.5 versus 0.08 min) (p < 0.001). Parental presence at the time of sleep onset and later and irregular bedtime routines were significantly associated with a reduction in total sleep time, longer sleep latency, and disruptive night awakenings (p < 0.001). These findings highlight the need for further studies to assess how to improve sleep patterns as a relevant modifiable lifestyle factor.Conclusion: A substantial percentage of the population perceived that their children slept poorly, which was evident in a variety of sleep patterns, including sleep duration and sleep quality. What is known: • Previous research has established that sleep difficulties among pediatric population affect up to 30% of all children and up to 20-30% of infants and toddlers. • A positive relationship between less parental bedtime involvement and sleep consolidation in infants and toddlers has been established. What is new: • More than a third of Spanish parents perceived their infants and toddlers sleep as problematic and their children reportedly have shorter night sleep hours, more night awakenings, and longer periods of nocturnal awakenings. • Later and irregular parental bedtime routines were associated with worst infants and toddlers sleep.

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.

Mother's prenatal and postpartum depression symptoms and infant's sleep problems at 6 months

Mother's prenatal and postpartum depression have been associated with infant's sleep problems. This study aimed to analyze (a) the effects of mother's prenatal and postpartum depression symptoms, including the effects of prenatal and postpartum anxiety and depression scores of the Edinburgh Postnatal Depression Scale (EPDS), on infant's sleep problems at 6 months, and (b) the interaction effect between mother's prenatal and postpartum depression symptoms and infant's sex on infant's sleep problems at 6 months. The sample was comprised of 164 mother-infant dyads whose mothers completed measures of depression at the third trimester of pregnancy, 2 weeks, 3 and 6 months postpartum and a measure of infant's sleep problems at 6 months (CSHQ-I). Mother's prenatal depression symptoms, specifically depression scores of the EPDS, predicted more infant's sleep anxiety and daytime sleepiness, while mother's depression symptoms at 2 weeks postpartum, specifically anxiety scores of the EPDS, predicted more bedtime resistance and CSHQ-I total scores at 6 months. Boys of mothers with more prenatal depression symptoms presented more sleep anxiety at 6 months. Both mother's prenatal and early postpartum depression symptoms have a negative effect on the emergence of infant's sleep problems. Additionally, boys seem more vulnerable to mother's prenatal depression symptoms.

Sleep habits and sleep characteristics at age one year in the ELFE birth cohort study

OBJECTIVE

Infant sleep plays a critical role in normal development. Sleep problems, including sleep onset difficulties (SODs) and night waking (NW), range from 20% to 30% in infants and young children and can be persistent over time up to adulthood. Young French children seem to have longer sleep durations and less sleep troubles than their counterparts worldwide. Here, we aimed at describing infant sleep characteristics (total sleep time (TST)/24 h, NW, and SODs) and associated sleep habits in infants at age one year from the French nationwide birth cohort Etude Longitudinale Française depuis l'Enfance (ELFE).

METHODS

This study included 11,783 infants with information on both sleep characteristics and sleep habits (parental presence when falling asleep, eating to fall asleep, sucking a pacifier or finger to sleep and sleep arrangement and location). Associations were studied by multinomial logistic regression analyses adjusted for familial and infant characteristics.

RESULTS

Mean TST was 13 h36 min including 2 h54 min of naps; 20% of the infants had TST ≤12 h/24 h. About 46% did not present SOD or NW, 16% had frequent SODs and 22% had NW > 1 night in 2. Parental presence, feeding to fall asleep and infant sleep arrangements were frequent in infants with short sleep duration (≤12 h/24 h), NW and SODs. Non-nutritive sucking was associated with risk of NW, SOD and TST >14 h/24 h. Parental room sharing was associated with NW.

CONCLUSION

This work provides new information on infant sleep arrangements and non-nutritive sucking that should be accounted for when considering sleep behaviors. In addition, most identified sleep habits associated with poor sleep characteristics may be amenable to change.

Longitudinal Study of Infant Sleep Development: Early Predictors of Sleep Regulation Across the First Year

BACKGROUND

An important developmental task for infants over their first few years of life is to learn to settle to sleep with a reasonably short latency, maintain sleep through the night and coordinate with family sleeping and waking schedules. A child who can reliably do this is exhibiting self-regulated sleep. Otherwise, children's sleep may have to be other (non-self) regulated to some degree and they may exhibit pediatric sleep disturbances (e.g., extended sleep latency, and/or frequent nightwaking); these are reported by 36-45% of parents of infants between ages four to 12 months.

PURPOSE

To answer the question: Can infant and parent factors observed at 1 month of infant age predict which infants will have regulated sleep at 6- and 12-months of age? Prediction from 1 month has not previously been investigated.

METHODS

In a prospective longitudinal study, the mothers of 52 typically developing infants completed 6-day sleep diaries at 1, 3, 6, 9 and 12 months from which a composite sleep score (CSS) was derived for each child at each month. Diary reliability was assessed once (for 54% of families) using all-night videosomnography.

RESULTS

At 6 months, CSS scores were distributed bi-modally and thus differentiated into two groups by an empirically observed CSS cutoff score, with a majority (56%) of infants classified as self-sleep regulated (S-R) and the rest as non-self sleep-regulated (NS-R). At 12 months, 72% could similarly be classified as S-R, while 28% exhibited some continuing sleep disturbance. Discriminant function analysis investigated the predictors of S-R vs NS-R group membership at 6 and 12 months from parent and child variables recorded at 1 month. Parent presence at sleep onset and less total infant sleep time predicted group membership at 6 months with 94% classification accuracy, and parental presence at sleep onset and frequency of infant night wakings predicted group membership at 12 months with 85% accuracy. At 1 month, parents of infants later classified as NS-R at 6 and 12 months had higher frequencies of all settling activities than parents of those later classified as S-R.

CONCLUSION

Variables measured at 1 month that predicted sleep status at 6 and 12 months were parental presence at sleep onset, frequency of infant night waking and total infant sleep time. The overall frequency of parent settling activities at 1 month also clearly differentiated the two sleep groups at the older ages. Parenting behaviours are modifiable factors and thus may have the potential for preventing pediatric sleep disturbances in children.

What does sleep hygiene have to offer children's sleep problems?

Sleep hygiene practices have been described extensively in the literature. There is considerably less clarity about relationships between particular elements of sleep hygiene and particular sleep outcomes, and which intervention approaches using sleep hygiene principles are effective. In this review, we describe themes extracted from a systematic review of the sleep hygiene literature. We systematically searched Psycinfo, CINAHL, Cochrane, Ovid Medline, Embase, and Web of Science Search Engines up to August, 2017. We included all studies that associated sleep hygiene (behaviors adjacent to bedtime and during the night) with sleep duration and/or sleep onset latency and/or night waking or that used sleep-hygiene based interventions to improve sleep duration and/or sleep onset latency and/or night waking (n = 44). We organized our findings into themes by age group, sleep hygiene factors, and interventions. We provide evidence-based recommendations about areas of sleep hygiene that have significant empirical support and those that require urgent attention.