Last few decades have witnessed a renaissance
of sleep research particularly about basic science, epidemiology and
disorders of sleep in children(1-2). Our current state of knowledge in
understanding epidemiology and nature of sleep problems in school
children leaves most pediatricians ill-equipped to guide parents and
take remedial measures for physical, psychological and academic
consequences of sleep problems in some children(3). Moreover, there is a
paucity of data in India on the prevalence of sleep patterns and
problems in children(4,5). We, therefore, carried out a preliminary
questionnaire survey for parents of school going children attending out
patient services of Advanced Pediatric Center, Chandigarh for routine
immunization or minor complaints.
Subjects and Methods
This was a cross-sectional prospective study
incorporating parental report about the sleep habits and problems of
school going children, conducted from September 2003 to March 2004. The
research ethics board of PGI, Chandigarh, approved the study.
We randomly recruited a convenience sample of 103
school going children (aged 3-10 years) from the out patient services of
Advanced Pediatric center while they waited for general pediatrics
appointment. Exclusion criteria were child with chronic illness, child
on long-term medication or having any neurological illness. After having
obtained the informed consent, a medical research worker collected
baseline demographic data that included: parents age, education,
socio-economic status, caste, religion, residential accommodation and
family organization. Specific child variables recorded included sex,
birth order, educational standard and number of siblings. The medical
research worker filled the questionnaire by enquiring, clarifying and
noting down the parents’ responses. The questions for this survey were
designed from literature review and clinical experience of authors. We
evaluated the sleep patterns along with certain common disorders of
sleep such as sleep walking, sleep talking, night mares , sleep terrors,
bruxism, nocturnal enuresis and sleep disordered breathing.
Data were summarized using descriptive statistics.
Chi-square test (Fisher’s exact test) and Mann- Whitney U test were used
for univariate analysis. Spearman’s correlations were computed for
various sleep-waking cycle-related variables. All P-values were
2-tailed.
Results
Our study sample had 103 children with the mean
subject age of 5.76 ± 1.89 years, 65 (63.1%) were boys, and 38 (36.9%)
were girls. They reported to the outpatient clinic for either
immunization (51), upper respiratory tract infection (22), diarrhea
(11), skin problem (1) or were normal, accompanying the sick child (18).
The average daily total sleep duration (nocturnal + daytime nap)
was 10.32 ± 1.18 hours, of which the night sleep duration was 8.77 ±
0.80 hours. The median onset time for nocturnal sleep was 10.00 pm
(range; 7.00 pm - 12.30 am) and the median morning wake up time was 7.00
am (range; 5.00-8.30) am. The percentage of children who took regular
daytime nap was 28.2%. The duration of daytime napping had highly
significant and positive correlation with the sleep onset timing
(Spearman’s r = 0.28; P = 0.009) and time needed to fall asleep
(Spearman’s r = 0.22; P = 0.04); whereas there was only a trend for
significant correlation with morning wake up time (Spearman’s r = 0.20;
P = 0.06). To put it simply, longer the duration of daytime napping,
significantly delayed was the time of onset of sleep at night. Children
with onset of sleep after 10 pm had significantly longer daytime naps,
got up significantly late in the morning and had significantly shorter
duration of night sleep. Less than half of the children (42%) had a
specific bedtime routine, which included bedtime story, bedtime patting,
music, milk bottle, pinching, clutching soft pillow, cuddly toys, thumb
sucking or crying to resist sleep. Nearly one-third (34%) of the parents
reported change in the sleeping schedule during the weekends. Two-third
children refused to sleep without the presence of their parents. Half of
the children feared sleeping alone; one-fourth required lights on; and
16% wanted the door to remain open. In 35% of children, parents had to
resort to threats in order to make their children sleep. TV viewing
interfered with the child’s sleep routine leading to delayed sleep in
39% of the children and awakening problems in the morning. Another 34%
children feared sleeping in the dark. The specific fears included
darkness, lizards, ghosts, and storms. 40% of the parents reported
problems in awakening their children which resulted in the child
resisting taking a bath, or going to the toilet, missing breakfast,
missing school conveyance, and cranky mood. However, daytime awakening
resistance did not lead to decrease in alertness, feeling of tiredness,
or increase in number of short naps among these children. Ninety three
per cent children shared the bed with their parents and no child slept
in a separate room, despite many reporting the facility of spare
bedrooms.
Forty-four (42.7%) children in our study had some
sleep problem, out of which 30 (29.1%) children had a single sleep
problem, 10 (9.7%) had two and 4 (3.8%) had more than two sleep
problems. Among the various problems, nocturnal enuresis and sleep
talking were reported most frequently in 19 (18.4%) and 15 (14.6%)
children respectively followed by bruxism in 12 (11.7%) while
sleepwalking was the least frequently observed in only 2(1.9%). Other
sleep problems reported by parents included nightmares in 7 (6.8%),
sleep terrors in 3 (2.9%) and snoring in 6 (5.8%) children. Out of 12
children with bruxism, 11 (91.7%) were male (Fisher’s exact test; P =
0.05) while there was no sex predilection for other reported sleep
disorders in our study. School related problems reported by parents were
tiredness (6.8%), frequent yawning (1%) and short naps (5.8%). On
univariate analysis, sleep related disturbances were significantly
higher if it was nuclear family (Fisher’s exact test; P = 0.01), mother
was younger in age (Mann Whitney U test; P = 0.04) and mother was less
educated (Mann Whitney U test; P = 0.04). No significant correlation was
observed with the socioeconomic status and the type of housing. However,
when these predictors were entered simultaneously into a logistic
regression model, only nuclear family remained as significant predictor
of sleep related disorders (odds ratio 2.41; CI; 1.04-5.57).
Discussion
School aged children are traditionally assumed to be
good sleepers, yet evidence from recent surveys as well as our study do
not support this assumption(6). As many as 42% of the parents reported
some form of sleep problem. Sleep problem is actually a sleep pattern
that is unsatisfactory to the parent, child or physician(7). To make the
definition of sleep problem even more difficult, families vary greatly
in their tolerance of their children’s sleeping habits; what one family
finds problematic, another family takes it as a matter of course. The
prevalence of sleep problems in the general population of children has
been estimated at approximately 5-16% for sleepwalking(2,8), 1-6.5% for
sleep terrors(9-10), 5-18% for nocturnal enuresis(11-12), and 5-10% for
sleep talking(13-14) which are comparable to the results in our study .
These estimates vary greatly because rarely are the same definitions for
the frequency of events used and there are no commonly accepted
definitions currently in use for these disorders. The possibility of
underreporting also cannot be ruled out in our socio-cultural scenario
where many of parents are either ignorant or extremely tolerant and
regard many behavioral problems as normal phenomena. Our study revealed
that nuclear family is an independent predictor of sleep problems,
though underlying causal factors cannot be deciphered due to
observational design of the study. Yet the recent trends for
urbanization, family nucleation and working-parent culture has altered
the traditional social fabric of our society, which might adversely
affect the conundrum of common childhood behavioral problems including
sleep. There is, however, scarcity of literature on this issue and a
community based case-control study may help in clarifying this issue
As expected, cosleeping was almost universal (93%) in
our study participants despite many reporting the facility of spare
bedrooms. Prevalence of cosleeping did not decrease with increasing age
as 91% of the children above 7 years (constituting 23.3% of the study
cohort) were still sharing the bed with their parents which is more than
68.7% reported by Kaur et al in the similar age group from urban Indian
families(4). The prevalence of co- sleeping is considerably higher than
that reported from the developed countries (5-52%)(15).
There are certain limitations in our study. It had
been shown that by restricting questioning to parents only, one-third of
all potential cases of sleep problems might go unnoticed. In order to
increase the sensitivity of screening children’s sleep problems, both
parents and children should provide information in epidemiological
settings as well as in clinical work. The study also failed to highlight
the underlying reasons for parents not seeking consultation despite
encountering sleep related problems in their children.
To conclude, though our results may not be
generalized to all populations, the overall prevalence of sleep related
problems in our study sample is enough to caution the pediatricians
about the need to sort through sleep problems in the office settings.
Contributors: BB designed the study, analyzed the
data and drafted the manuscript. PM contributed her expertise in helping
in designing the study and revising the manuscript and SK collected the
data.
Competing interests: None stated.
Funding: Postgraduate Institute of Medical
Education and Research, Chandigarh.
