Pattern of Sleep in Infants and Toddlers Visiting at a Teaching Hospital in Lalitpur

Introduction: Sleep is an integral part in a child's health and development. During different stages of development, there are aberrations in normal physiology of sleep which make children more susceptible to various types of sleep problems. This study was conducted to identify sleep pattern and sleep problems in Nepalese children using Nepali translation of Brief Infant Sleep Questionnaire (BISQ) screening tool. Materials and Methods: This was a descriptive cross-sectional study. Data were collected from parents of children aged 6 to 36 months attending paediatric outpatient clinic for general health checkup from July 2013 to December 2013. Nepali translation of the BISQ was used as a screening tool for sleep problems in this study. Results: The study included 553 children (52.4% boys). Mothers completed the questionnaire in 92% of children. Mean total duration of sleep in 24 hours was 11.7 ±1.7 hours. Respondents reported sleep problem in 16.9% of children whereas 20.3% of children had sleep problems according to BISQ criteria. As per this criteria, 2.7% of children had total sleep duration less than 9 hours, 5.9% of children had total night awakening duration of more than one hour, 13.9% of children had night waking >3 times. These BISQ sleep parameters differed significantly in children with and without sleep problems (p<0.001). In addition, children with sleep problem took longer time to sleep than children without sleep problems (p<0.001). Conclusion: Sleep problems are common in Nepalese infants and toddlers according to the BISQ. Screening for sleep problems is highly recommended during health care visits given the prevalence of sleep problems identified by this study to reduce their potential adverse impact.


Introduction
S leep is a basic biologic func on of a child and cons tutes a signifi cant propor on of life.Sleep pa ern varies with age and plays a vital role in a child's growth and development.In addi on, sleep is strongly infl uenced by environmental and cultural factors 1,2   .Hence normal sleep pa erns should be defi ned based on child's developmental, sociocultural and environmental factors.Sleep pa ern of children as well as parental percep on to sleep problem diff er in Asian countries from the western countries 3 .These factors should be iden fi ed for understanding sleep problems.
Sleep problems are also associated with various other problems like learning disabili es, impaired cogni ve func ons, behavioural disorders, and emo onal problems 4 .Although matura on leads to improvement in some aspects of sleep pa ern, sleep problems in early childhood are likely to persist to later years 5 .
Sleep problems are common in up to 25% of children 2 .Yet, these problems are s ll under-recognized and neglected by physicians and parents in common prac ce 6 .
The English version of Brief Infant Sleep Ques onnaire (BISQ) is one of the screening tools used to iden fy sleep problems in children below 36 months age 7 and which has been used in various studies worldwide 8,9 .It is a simple tool and cons tutes of 11 ques ons and can be completed by responders within 5 to 10 minutes.
Currently there is a lack of data regarding sleep behaviour and sleep related problems in young Nepalese children.Therefore this study was conducted to iden fy various pa erns of sleep and, common sleep problems among infants and toddlers in Nepal using BISQ.In addi on to documen ng the prevalence of sleep problem in Nepal, the fi ndings could be compared to norma ve data of children from diff erent parts of world.

Materials and Methods
This was a descrip ve cross-sec onal study conducted among children aged six months to thirty six months a ending paediatric out-pa ent clinic for general health check-up from July 2013 to December 2013.Ethical clearance was obtained from ins tu onal review commi ee prior conduc ng the study.Parents or caregivers were asked to complete the translated Nepali transla on of BISQ a er an informed wri en consent.Children with any acute or severe medical problems or on s mulant medica ons poten ally aff ec ng sleep were excluded from the study.
The BISQ is a screening tool to detect common sleep problems in infants and toddlers 7 .This ques onnaire was translated in Nepali language using standard technique and details have been described earlier 10 .This Nepali translated version the BISQ was used in the current study.
Children were screened by one of the researchers for any acute illness or medical problems and parents were asked to fi ll up the Nepali version of BISQ.In case, a ending guardian was illiterate, an independent person was asked to read the ques ons to the guardian and complete the ques onnaire.
We defi ned a sleep problem if (a) three or more night awakenings were reported; (b) dura on of nightme awakening was more than 1 hour; or (c) the total dura on of sleep was less than 9 hours 7 .
Data was analyzed with SPSS 16.0, using two independent sample t-test for normally distributed numerical variables and Mann-Whitney U test for nonnormally distributed numerical variables and binomial logis c regression for categorical data to assess the associa on between various sleep parameters and p<0.05 was considered sta s cally signifi cant.

Results
The survey was successfully completed in 553 children a ending paediatric out-pa ent clinic for general health services.Out of which, 290 (52.4%) children were boys (Table 1).Mothers completed the ques onnaire in 510 (92.2%) children.Mean age of children was 18.9 ±8.8 months.
Sleep characteris cs are summarized in Table 2. Almost all (99.3%) children slept in the same room with either parents or grandparents whereas bed sharing with parents or grandparents was seen in 93% of children.Most of children preferred lateral posi on during sleep and almost half of children required feeding to fall asleep.
Other sleep parameters are presented in Table 3. Overall median sleep me was 8:30 PM and mean total sleep dura on was 11.7±1.7 hours which decreased with increasing age.However when analyzed sleep me in day and night, mean night me sleep dura on increased and mean day me sleep dura on decreased gradually with increasing age.
Among children who met our criteria for a sleep problem according to the BISQ, 2.7% had total sleep dura on less than nine hours, 5.9% had night waking dura on of more than one hour and 13.9% had night waking more than three mes in a night.Signifi cant diff erences were noted between the BISQ measures in respondents who self-iden fi ed sleep problem and those who did not: mean total sleep dura on in hours (11 Similarly, sleep problems were observed in 25.4%, 21.8% and 11.9% children in age groups 6-12 months, 13-24 months and 25-36 months respec vely which was sta s cally signifi cant (p=0.006).
There was no signifi cant associa on of sleep problem with place and posi on of sleep, bed me rituals or birth order.
Parent percep ons of sleep problems in their children are shown in Table 6.Inadequate sleep, bed me resistance and night awakening were the common parental concerns.Interes ngly sleeping in prone or lateral or supine posi on was considered as a problem by few parents.

Discussion
Normal sleep pa ern in infants and toddlers is infl uenced by age, socio-cultural prac ces and the environment in which a child grows in interrela onship with other developmental processes.The percep on of parents regarding sleep pa ern of their children is also determined by socio-cultural prac ces dealing with sleep and educa on related to sleep hygiene and is diff erent worldwide.Therefore, sleep problems in children may occur as a result of derangement in any of these mul ple factors.
This study describes the presence of sleep problems in Nepalese children.Sleep problems were iden fi ed in 20.3% infants and toddlers based on BISQ criteria which was lower than that observed (33%) in another study in Indonesia using the same criteria 8 .
Co-sleeping of children with parents is a common and acceptable prac ce as it is considered unreasonable to put children to sleep alone in various communi es.In Nepalese society, as in other Asian countries 12 , co-sleeping up to a certain age is also a cultural norm and a separate bed room for children is not common.The same issue was refl ected in this study where 92% of children co-slept with parents, similar to children in countries predominant Asian (64.5%) 3 , India (96%) 13 and Indonesia (99.3% ) 8 .However, bed sharing with parents was very low (7.2 to 16.6%) in European countries and Australia 5,9 .Co-sleeping per se was not found to be associated with increased sleep problems in early childhood in previous studies 14 .However trying to get children asleep and subsequently falling asleep at a similar me may disturb parents' sleep quality, which may subsequently aff ect that of their children 14 .
Bed me rituals also diff ered between Asian and Caucasian children.Most Caucasian children (57%) were put to sleep independently in their own crib or bed compared to 4% in Asian children 15 .In Asian children, feeding was observed as the most common bed-me ritual in 60% of children 8 .There was a high level of parental involvement in sleep onset as well as maintenance of sleep in children in the present study similar to observed among children in Asian countries 15 .Feeding was the most preferred method of sleep ini a on among Nepalese children in this study while co-sleeping was most common method of maintaining sleep.
Sleep-wake regula on and its maintenance is a developmental process which matures rapidly during infancy and early childhood and the process con nues throughout the childhood period.Circadian rhythm of sleep develops during early infancy and day me napping con nues ll four years of age 16 .Similarly night awakenings are frequent in infancy and may be as high as 30% which gradually decrease over the age 17 .Diffi cul es in matura on of sleep are clinically evident in the total very short sleep episodes and in mul ple and extended night awakenings, which has an inverse rela on to age 18 .This normal physiological pa ern of decreasing total dura on of sleep and dura on of night awakening according to age was also refl ected in this study.
A systema c review has described total sleep dura on of 12.7 hours during infancy, 12.6 hours at one to two years and 12 hours at two to three years of age 18 .However total sleep dura on was shorter in Asian children (12.31 hours) in comparison to western countries (13.02 hours) 3 .Total sleep dura on of children in the current study was also within the lower range of sleep dura on among children of primarily Asian origin and was similar to lowest dura on which was observed among children in Japan (11.6 hours) 3 .
A large study among children aged below three years showed Asian children (9.44 PM) have signifi cantly late bed me than Caucasian children (8.42 PM) 3 .This was also refl ected in the current study as the median sleep me of 9.15 PM in our children.
This study showed higher rate of night awakenings as compared to other countries.This may be explained with the fi nding that almost all of children slept with parent and parent will be more aware of these night awakenings.Mean me to put to sleep was 20 minutes in Asian children 8 , which was similar to this study.In a systemic review of children below two years of age sleep latency was found to be 19 minutes 18 .Sleep latency is an important indicator because many parents consider small dura on of sleep latency as the most important part of healthy sleep and diffi culty pu ng their children to sleep as a worrisome sign.However, it is important to remember parental repor ng of sleep latency me may be exaggerated as compared to latency me measured by polysomnography 19 .
The factors most concerning to parents in this study were longer me to get asleep (sleep onset latency), frequent night awakening (poor sleep maintenance) and shorter sleep dura on, which were in concordance to other studies 5,13,17 .
Parental percep on to sleep problems vary across diff erent cultures and age groups and parents of Asian origin are more likely to perceive problem in their children's sleep 3 .Parental percep on as sleep problem varied from 11% to 76% in studies from Asian countries 3 .Whereas in an Indonesian study using BISQ, 15.7% of parents perceived that their children have sleep problem 8 .In contrast, parental percep on as sleep problem was seen only in 10% in developed countries from Europe and United States 5 .These data along with our study suggest that cau on must be exercised when elici ng history regarding parentdefi ned sleep problem in children especially from parents from Asian background.Therefore it is ra onal to screen children using structured sleep ques onnaire rather than relying on parental percep on to detect sleep problems and followed by detailed evalua on if needed.
This study highlights the existence of sleep problems in Nepalese children as well as limita ons of parental percep on of sleep problem.In general, there is lack of importance given to sleep problems by caregivers as well as even health care providers who may miss iden fi ca on of sleep problems in a child 5 .Hence the use of structured screening ques onnaires during hospital visits is recommended to screen for sleep problems and those children with sleep problem should further be evaluated in detail and appropriately intervened in presence of sleep problems.
Reporter bias and inapplicability in children with developmental disorders like au sm are the limita ons of this study.Similarly cau on should be exercised to generalize this data to whole of Nepalese children as this was conducted among apparently well children visi ng a hospital in a semi-urban community.

Conclusions
Most infants and toddlers slept in same bed with parents.Most children were dependent on parents for the ini a on as well as maintenance of their sleep.Nepali transla on of BISQ may be used to screen for sleep problems.As in other parts of world, sleep problem was common in Nepalese children.Health care providers should be aware of existence of sleep problems in Nepalese children and hence it is impera ve to screen children during hospital visits by using screening tools.Further large scale popula on based studies will be able to ascertain an exact incidence of sleep problem in Nepal.In addi on, studies exploring the nature of these sleep problems are required.

Table 2 :
Sleep characteris cs of children

Table 3 :
Sleep parameters according to age group

Table 4 :
Sleep characteris cs of children according to sleep problems perceived by respondents

Table 5 :
Propor on of children with sleep problems (as defi ned by BISQ) according to age groups

Table 6 :
Parent reported sleep problems When we compared children with or without sleep problem as defi ned by BISQ criteria, mean day me sleep dura on was not sta s cally diff erent between these two groups of children however, total sleep dura on and night me sleep dura on were signifi cantly diff erent between children with sleep problem and without sleep problem (total sleep dura on 11.1±1.9hours versus 11.8±1.7 hours, p<0.001; night sleep dura on 8.8±1.3 hours versus 9.6±1.1 hours, p<0.001).Children with sleep problem had mean number of night awakenings of 3.9±1.5 per night as compared to 1.7±1 per night in children without sleep problem.Similarly dura on of night waking was signifi cantly higher in children with sleep problem (55.5±55.7 minutes) than children without sleep problem (15.3±15.8,p<0.001).