The majority of children and adolescents experience sleep problems
at some stage. Although these may not attract formal diagnoses,
these problems nonetheless are often the source of considerable
distress for both the child and their family, resulting in
diminished functioning and well-being for all concerned (Mindell,
1993).
Sleep disorders are classified into two major
categories, dyssomnias and parasomnias. The following discussion of
sleep difficulties will be presented within the context of these two
categories. Finally, a number of treatment approaches for sleep
disturbances will be outlined.
The Phenomenon of
Sleep
The alternation between sleeping and waking
typically follows a 24- hour cycle, which is synchronised to the
physical and social environment. The human sleep-wake cycle tends to
display a longer period, of approximately 25 hours, when an
individual is deprived of environmental time cues. It is understood
that this free-running period reflects the spontaneous rhythm of the
endogenous circadian pacemaker, commonly referred to as the
biological clock (Moore-Ede, 1982).
Sleep occurs in a
rhythmic pattern that is characterised by five distinct
physiological stages, that are cycled through several times during
the course of a night's sleep. Of these stages, the most important
appear to be rapid eye movement (rem) and slow wave sleep (sws), as
they are believed to support a number of important functions
(Moore-Ede, 1982). Although far from conclusive, evidence suggests
that sws may serve restorative and regenerative functions in regions
of the cerebellum (Carlson, 1991; Horne, 1992).
While it does
appear probable that sleep involves restorative and information
storage processes, a comprehensive and unequivocal explanation to
the question of why we sleep is still yet to be provided.
Nevertheless, the debilitating effects of inadequate sleep are a
sound indication that inadequate sleep, at the very least, has
secondary effects that are not conducive to optimal functioning and
wellbeing, and at worst, may have primary effects that impede
physical and cognitive development.
The Normal
Developmental Sequence of Sleep
Although sleep is
controlled by the same neural mechanisms for all people, the
structure and pattern of sleep varies across different age groups.
Children are born with a multiphasic sleep pattern that does not
develop into an adult-like monophasic sleep pattern for a number of
years. The emergence of a mature sleep-wake rhythm is a
developmental process, which entails the child learning to adapt his
or her sleep to comply with the 24-hour environment. Gradually the
child’s sleep-wake pattern will consist of progressively shorter and
fewer nap’s during the day, and a longer more sustained sleep
episode at night. A monophasic pattern of sleep, synchronised to the
environment, commonly emerges between the ages of 2 and 5, when the
child completely abandons the daytime nap. The total amount of sleep
required each 24-hour period, and the total amount of sleep time
spent in rapid eye movement (rem) sleep, also follows a
developmental time course. It steadily decreases with age, from
approximately 16 hours per day in newborn babies, to approximately 8
hours per day in 17 year old adolescents (Horne, 1992; Edwards &
Christopherson, 1994). Thus, the normal range of sleep duration in
children varies enormously with age.
In addition to
considerable differences in the sleep of children at different ages,
there is considerable variation in the sleep patterns of children of
the some ages. For example, the parameters for normal sleep in a
typical 5 year old ranges from about 8 to 13 hours of sleep, with or
without daytime naps. Because of this enormous natural variance that
exists within sleep, it is difficult to definitively pinpoint where
normal sleep finishes and abnormal sleep begins (Horne, 1992).
Parasomnias
Overview of Parasomnias
Nightmare Disorder
Sleep Terror Disorder
Sleepwalking Disorder
NOS
Parasomnias
are disorders of arousal, partial arousal and sleep stage
transitions, that is, the activation of the physiological systems at
inappropriate times during the sleep cycle. The systems involved are
the autonomic nervous system, motor system and the cognitive
processes. People who suffer usually present with complaints of
unusual behaviour during sleep (American Psychiatric Association,
[APA], 1994).
Description of Selected Disorders
(1) NIGHTMARES (connected to the
REM sleep cycle)
Diagnostic
Criteria
- essential feature is the repeated occurrence of
frightening dreams that lead to awakenings from sleep;
- become fully awake, oriented and alert
- significant distress or occupational functioning
- occur during REM (rapid eye movement) sleep stage;
- nightmares are not part of another disorder
Differential Diagnosis
- during middle and latter portions of the night during
REM sleep;
- vivid dream imagery;
- any verbalisations are subdued;
- moderate physiological arousal;
- slight or no movements;
- easy to arouse and responsive to environment;
- episodes are frequently remembered; (APA, 1994;
Wicks-Nelson & Israel, 1997)
Prevalence
common; 10 and 15% of children are
affected.
Onset
especially between the ages
of three and six
Course
When the frequency is
high (several times per week), dreams become a source of concern for
the parent and child. Some say if dwelled upon, they can also
exacerbate the problem. Children tend to outgrow the problem (APA,
1994).
Aetiology
Previously held theory that
nightmares are a manifestation of anxieties the child faces no
longer are supported; no theoretical framework explains
satisfactorily the development of night mares. Current thoughts tend
to opt for multiple causality
- developmental,
- physiological,
- environmental factors (Wicks-Nelson & Israel, 1997).
(2) SLEEPWALKING (connected to slow wave
sleep)Diagnostic Criteria
- Repeated episodes of rising from bed during sleep and
walking about;
- Child leaves bed and walks around; can be like an
automaton
Occurs during stages of SWS;
- No memory of it the next day
- Within several minutes after awakening, no impairment of
mental activity/behaviour (could be confused)
- Distress or impairment in social/ occupational other
areas
- Not the result of other physiological disorders
Differential Diagnosis
- child sits upright in bed; eyes are open but appear
‘unseeing';
tend to move in a confused and clumsy manner
that becomes more coordinated;
- stays in bedroom, generally, looking for something
specific;
- it is impossible to catch their attention- if left alone
go back to their bed;
- navigation around room through memory of the room layout
(which seems to be heightened while asleep)
- (if blindfolded and did a similar route when awake will
not have the same navigational success and will more likely
bump into things);
- sometimes injuries occur
- sometimes adventurous activities occur-going to the
fridge, dressing; note: if the activity becomes more
complex-dress then ride a bike this is less likely to be
sleepwalking and more a confusional arousal into true
wakefulness;
- disturbing mental events can occur (APA, 1994;
Wicks-Nelson & Israel, 1997).
Prevalence
10 and 30% of children have one episode.
Actual disorder with frequent persistent recurrences is much lower,
1-5%. There is an age peak at 12 years. Persistent sleepwalking
occurs in 1 to 6 % of population.
Onset
The
onset is somewhere between the ages of 4 and 12. The episode occurs
in first one to three hours following sleep onset (when SWS is most
prolific)
Course
The episode may last for a
few seconds or thirty minutes or longer. The disorder itself peaks
in adolescence -tends to disappear by late teens (it is outgrown)
(APA,1994; Wicks-Nelson & Israel, 1997).
Aetiology
- not the acting out of a dream as originally thought
- a characteristic EEG pattern has to precede each episode
- this pattern exists in 85% of all children in the first
year of their life but is present in only 3 % of 7-9 year
olds
the central nervous system is of significance in
this disorder (Wicks-Nelson, 1997)
- however, still a possibility of psychological or
environmental factors.e.g. anxiety, in some children the
worry can be minor, such as the loss of a favorite toy; in
serious cases there might be underlying emotional conflict
(Horne, 1992; Wicks-Nelson & Israel, 1997).
- some hereditary basis eg family history in up to 80% of
individuals who sleep walk; risk is increased up to 60 % if
both parents have a history; about 10 - 20 % of individuals
have a first degree relative who sleep walk (APA, 1994);
- earlier studies indicated that this disorder with
enuresis both reflect some form of stage 4 sleep problem.
However, this view is now strongly contested as a result of
research which shows that sleepwalkers remain in SWS while
walking, showing minimal arousal (Horne, 1992).
(3) NIGHT TERRORS (connected to SWS sleep
cycle)Diagnostic Criteria
- Recurrent episodes of abrupt awakening from sleep,
during first third of night, child wakes with scream, cry;
- Intense physiological arousal (increased heart rate,
profuse sweating, pupils dilated) and fear; occurs during
non-REM sleep, that is SWS; and so, can be associated with
sleepwalking;
- Difficult to comfort the child;
- Very limited or no memory of the episode;
- Episodes cause significant distress/ impairment in
social/occupational functioning;
- The disturbance is not due to direct physiological
effects of a substance;
Differential Diagnosis
- individuals can suffer isolated episodes of sleep
terror, but a disorder is diagnosed on above criteria;
- after the fright the child can awaken a little but can
be disoriented and confused;
- there is motor activity, agitation, child is difficult
to arouse and unresponsive to the environment;
- verbalisations usually present;
- sudden, horrifying sensations with images that shock the
sleeper into wakefulness;
- sits up abruptly in bed, appears to be staring at a
"monster", flushed skin, sweating unable to respond to
others (APA, 1994).
Prevalence
- rare occurrence 1-4% (but when occurs can also be
frightening to the parents seeing their child in such a
state of distress and unable to comfort);
- more common in males and older children (where there can
also be sleepwalking);
Onset
- occurs between the ages of 4 and 12;
- episode: during SWS and at a constant time = 2 hours
into sleep;
Course
- episode can last several minutes (1-10 minutes) maybe
longer;
- night terrors can continue into adulthood (but less
common ); generally, resolves spontaneously during
adolescence (APA, 1994; Wicks-Nelson & Israel, 1997).
Aetiology
- similar theoretical construction as sleepwalking (occur
during a similar time slot):
- a characteristic EEG pattern has to precede each episode
the central nervous system is of significance in this
disorder;
- however, still a possibility of psychological or
environmental factors (Horne, 1992; Wicks-Nelson & Israel,
1997)
DyssomniasThe
disorders that are raised here differ from those that are listed in
DSM-IV (APA, 1994). Such differences may be accounted for by the
fact that some disorders which are listed in DSM-IV (APA, 1994) are
rarely or never diagnosed in children. Reference is made to the
International Classification of Sleep Disorders: Diagnostic and
Coding Manual [ICSD] (Diagnostic Classification Steering Committee
[DSSC], 1990), a comprehensive text of sleep disorders with a
broader range of disorders covered, particularly those relevant to
children, than DSM-IV (APA, 1994).
Dyssomnias are noted in
DSM-IV (APA, 1994) as disorders of initiating or maintaining sleep,
or of excessive sleepiness, which result in a disturbance in the
quality, amount, or timing of sleep. Problems of sleep quality are
expressed as not feeling rested after sleep, sleep amount problems
are characterised as being unable to maintain sleep or excessive
sleeping, and sleep timing problems are noted as an inability to
fall asleep during conventional sleep times (Mindell, 1993).
Problems of sleep timing contain reference to the inability to sleep
during conventional sleep times (Mindell, 1993), which highlights
the social construction that is inherent with the sleep disorders
and should be considered during discussion of these disorders.
Factors involved in sleep disorders
Wicks-Nelson and Israel (1997) note that childhood sleep disorders
have been viewed as manifestations of a child’s neurophysiological
development and have been considered to remit with increasing
development. However, this picture is not entirely true as was
demonstrated in a recent study that suggests child, parental and
environmental factors play a role in the development of sleep
disorders. Minde, Popiel, Leos, Falkner, Parker, and Handley-Derry,
(1993) examined the sleep of children, between the ages of 12 and 36
months, who had been rated as either good or poor sleepers. The
children’s mothers kept sleep diary records, which indicated that
children rated as poor sleepers, had more night awakenings. However,
filmed recordings of both the good and poor sleepers revealed no
difference in the number of night awakenings between the groups.
Poor sleepers were not able or unwilling to return to sleep and woke
their parents. Good sleepers were able to return to sleep adopting
behaviours such as looking around or self-quieting by hugging a toy
or sucking a thumb.
This study highlights a number of
possible factors that may be involved in a sleep disorder. However,
regardless of the cause these problems can cause considerable
distress for both the child and family members (Scott & Richards,
1990; cited in Horne, 1992; Wiggs & Stores, 1996).
Difficulties in going to sleep
Horne (1992) notes a
number of problems associated with getting children to initiate
sleep, particularly those that involve time-consuming bedtime
rituals or particular circumstances for the initiation of sleep.
These problems are also listed in the icsd (dcsc, 1990) as
Limit-setting sleep disorder and Sleep-onset association disorder.
However, before such problems are diagnosed physical or
psychological problems such as colic, milk-intolerance, and actual
fears of sleep or nightmares should be excluded (Horne, 1992).
Limit-setting sleep disorder is characterised by a child’s
stalling or refusing to bed and is thought to occur in 5-10% of the
childhood population (dcsc, 1990). It is thought that this problem
is environmentally related and can be associated with problems for
caretakers (Mindell, 1993). Parents of children with Limit-setting
sleep disorder experience increased depressive symptomatology,
decreased marital stress, and increased anxiety (Mindell, 1993).
Sleep-onset association disorder is an impairment or absence of
sleep-onset in the absence of a particular set of circumstances or
objects, for example, a pacifier or bottle, being rocked to sleep,
or the presence of a parent (dcsc, 1990). Sleep initiation problems
are not encountered when the objects or circumstances are present,
although problems of sleep initiation and maintenance (night
awakenings) can occur in their absence (dcsc, 1990). Similarly to
Limit-setting sleep disorder, this disorder is thought to be an
environmentally related problem and is thought to occur in
approximately 15-20% of children between the ages of six months and
three years, although it may persist after this time (Mindell,
1993).
Milk-intolerance
Although this
disorder is listed in the icsd (dcsc, 1990) very little is known
about the disorder beyond the fact that milk-intolerance can lead to
sleep initiation and maintenance problems. The disorder was
highlighted in a study that examined a clinical sample of 147
children referred for sleep problems (Kahn, Mozin, Rebuffat,
Sottiaux, & Muller, 1989). Of the 147 children 58% were diagnosed
with inappropriate sleep habits, 10% had minor problems (the
majority of these being parental anxiety), 5% suffered a poor
sleeping environment, and 15% were diagnosed with various
parasomnias. The remaining 12%, despite symptoms of an average
duration of 13 months, particularly frequent night awakenings, did
not receive a diagnosis. An intolerance to cow’s milk was suspected
as the cause for these children’s symptoms and all (n=17) were
placed on a diet that excluded diary products. For 15 of the 17
children sleep was normalised within five weeks of commencing the
diet. Subsequently, children were given a double blind milk
challenge with symptoms recurring in 14 of 15 children. The milk
challenge was again performed at 1-year follow-up with 10 children.
All but one child reacted as before with the initial challenge.
Intestinal Dysbiosis
Intestinal
Dysbiosis is the term used to describe a disordered ecology of
the bacteria that normally reside in the gut. Some bacteria
populations can become overgrown for a variety of reasons, at the
expense of other varieties. Some of these bacteria produce toxic
byproducts that triggers the brain to function over actively,
keeping the person awake and causing anxiety and sometimes panic
attacks. If the bowel function is not normal in form and regularity,
contact the clinic for advice.
Night-time feeding
Due to the difficulty in distinguishing between what is
abnormal and normal night-time feeding is a contentious area
surrounded by much dogma (Horne, 1992). It is thought that by around
the age of six months an infant should be able to acquire all of its
food needs during the day (Douglas & Richman, 1982; cited in Horne,
1992). Horne (1992) suggests that an infant awakening more than
three to four times per night for substantial feeds would be
considered abnormal, whereas an infant waking only once or twice per
night for short feeds would be considered normal. Nighttime feeds
that involve large quantities of food can create compounding
problems, such as wet nappies, discomfort and further awakenings,
and also to a reduced daytime intake of food (Ferber & Boyle, 1983;
cited in Horne, 1992).
Very little information is provided on
this topic although it has been noted that breast fed babies are
more likely sleep through the night at a later age than bottle fed
babies (Wright, Macleod, & Cooper, 1983; cited in Horne, 1992).
Sleep-wake rhythm disorder
The timing of
sleep is under the control of the circadian timing of our sleep-wake
cycle and can become disordered relative to the exogenous or
societal demands regarding the timing and duration of sleep
(Weitzmann, Cziesler, Coleman, Speilman, Zimmerman, & Dement, 1981;
cited in Horne, 1992). Some individuals are unable to fall asleep
until around 3-5 a.m. after which sleep is of good quality but is
not sufficient in quantity due to societal demands to rise (Horne,
1992).
The disorder is thought to develop after a succession
of progressively later times of sleep onset. Individuals who develop
this disorder are thought to suffer from a reduced ability to
advance the phase of their sleep-wake hours, or to move their
sleep-wake timing to earlier clock hours (Mindell, 1993).
Sleep-wake rhythm disorder is thought to be a disorder experienced
more so by adolescents that children with prevalence estimates from
survey data suggesting that up to 7% of adolescents suffer from a
disorder of the sleep-wake rhythm (Mindell, 1993). The course of the
disorder may be chronic, lasting anywhere between one year or
decades, although cases where the disorder has spontaneously
corrected itself have been reported (Mindell, 1993).
Sleep apnea
Sleep apnea has been associated with
excessive daytime sleepiness and involves an obstruction of the
airways during sleep that leads to a decreased oxygen saturation of
the blood (Mindell, 1993). The decreased oxygen saturation causes
the sufferer to awaken briefly and to be frequently aroused many
times throughout the night (Mindell, 1993).
Sleep apnea is
associated with heavy snoring and is thought to be most commonly
caused by enlarged tonsils (Horne, 1992). Other causes of sleep
apnea include a small oropharynx, obesity (especially of the neck),
micrognathia (an unusually small jaw), chronic upper airway
infection, rhinitis (an inflammation of the mucous membranes of the
nose), and hayfever (Horne, 1992).
The disorder is usually
treated by a form of corrective surgery, which frees the obstructed
airways allowing normalised breathing during sleep, such as
tonsillectomy (Horne, 1992) or surgery to correct jaw size or the
oropharynx.
Treatment
Nightmares
Because there seems to be
multiple causality of nightmares (eg. Developmental, physiological,
and environmental factors), no single treatment formula can be
considered the most effective.
Anxiety is generally
considered to form the basis of nightmares, however, and individual
assessment is necessary, so that appropriate treatment can be
instigated. For example, family stresses such as marital disharmony
may be identified as needing to be targeted, in the treatment of the
child's nightmares.
Consistent with anxiety being viewed as
the basis of nightmares, the majority of treatments tend to be
anxiety reduction techniques such as relaxation training and parent
counselling (Wicks-Nelson & Israel, 1997). Tranquillisers are
considered helpful only as a stopgap measure (Horne, 1992).
Night Terrors
It would
depend on the extent of the problem, as to whether treatment is in
fact indicated for night terrors. In many cases, treatment may not
be indicated because the episodes disappear spontaneously. However,
should intervention be needed, similar treatment approaches are
often taken for night terrors, as for nightmares. A combination of
medication such as imipramine, education regarding the nature of the
disorder, relaxation techniques and parent counselling have been
reported as highly effective (Wicks-Nelson & Israel, 1997).
There is also the pre-emptive approach, in which the child is woken
before the night terror occurs. This procedure involves a week of
recording the exact time the night terrors occur, which is often
around 2 hours into sleep. Then, for the next few nights, the child
is gently woken about 15 minutes beforehand, kept awake for about 5
min, then allowed to return to sleep (Lask, 1988; cited by Horne,
1992).
The likelihood of a night terror occurring on these
nights is reduced, and with the pattern having been broken, it is
claimed that the night terrors are less likely to return on the
following nights when the child sleeps through without interruption.
However, all that may happen is for the night terror to reschedule
itself elsewhere in sleep (Horne, 1992).
While this might be
a useful component to treatment, on it’s own it doesn't treat
possible underlying causes such as daytime stresses and anxiety.
Perhaps a combined approach would produce positive outcomes.
Sleep Walking
Because
episodes of sleepwalking may be triggered by anxiety, one of the
best known treatments is reassurance of the parents, as the more
worried they become, the more it will be sensed by the child. This
can result in increased anxiety and more sleepwalking. Sometimes,
with parental support, the episodes often resolve themselves (Horne,
1992).
Sleepwalking can also be, at times, a benign habit
that can be broken by altering the child's sleeping circumstances,
for example, by changing the bedroom for a few days (Horne, 1992).
It is considered unwise to try waking up a sleepwalking child as
this may result in distress for the child. It is best to guide or
carry them back to bed (Horne, 1992).
Difficulty in
Going to SleepBehavioural approaches are considered
more successful than sleeping tablets, however before behavioural
techniques are applied, causes such as colic, milk intolerance or
real fears of sleep or nightmares need to be ruled out (Horne,
1992).
Provided the child experiences feelings of safety and
security during waking hours, the most effective behavioural
technique is systematic ignoring. The procedure involves tucking the
child in at bedtime, and then leaving the bedroom without going back
in until the child is asleep, or failing that, only briefly entering
the bedroom for reassurance that the child has no physical
complaint, and then leaving immediately. The first night or so is
usually quite traumatic for all concerned, but if implemented
consistently and correctly, progress is rapid (Horne, 1992).
Half way measures, such as the parents allowing the child to cry for
twenty minutes, and then intervening, are counter-productive as the
child's crying behaviour is positively reinforced (Horne, 1992).
If parents are not prepared to let the child undergo a few
nights of what appears to be traumatic crying, then this procedure
is not recommended. Instead, a protracted withdrawal technique can
be used. This can take many nights, and involves the parent
gradually withdrawing from the scene (Horne, 1992).
For the
child who wakes up in the night and demands that a parent
accompanies him/her back to sleep, scheduled awakenings can be used.
This is based on the tendency for most of these children to wake at
fairly constant times (Horne, 1992). The parent gently arouses the
child about 30 min before the typical spontaneous awakening, and
consoles the child. The child then falls back to sleep without the
usual waking occurring. The routine continues for several nights
until all the spontaneous wakenings have disappeared, and all the
child's awakenings are under the control of the parent rather than
the child. The final step is to gradually eliminate these scheduled
awakenings until the child no longer wakens and cries at night. In a
study by Rickert and Johnson (1988; cited by Horne, 1992), it was
found that this procedure was roughly as effective as systematic
ignoring, but generally took 6 weeks to achieve results, as compared
with systematic ignoring which took 1 to 2 weeks.
Parents
must be clear that really, none of the methods is easy, and the
failure rate can be high.
Night time feeding
Because large night time feeds can create or compound
sleep-wake problems, through wet nappies, or discomfort, for infants
over 6 months, it is recommended that such feeds be minimised or
stopped (Horne, 1992). The best method for this is gradual reduction
over a 2 week period; decreasing the milk available, and increasing
the acceptable time between feeds. Success is usually marked, and
parents often surprised by how quickly the infant adapts (Horne,
1992).
Milk intolerance
Where cows
milk intolerance is suspected, the obvious treatment is to withdraw
milk products from the baby's diet. In a study by Kahn, Mozin,
Rebuffat, Sottiaux and Muller (1989; cited by Horne, 1992), sleep
was normalised within 5 weeks in 15 out of 17 subjects and
follow-ups involving reintroduction of milk induced the reappearance
of sleep difficulties for most of the babies.
Sleep-wake rhythm disorders
In treatment, it is
easier to move the circadian clock forwards than backward by
extending the day. This is called Phase Delay and is accomplished by
going to bed 2 to 3 hours later each day, for 7 days. For example,
if sleep onset is usually 4am, then successive bedtimes would be:
7am, 10am, 1pm, 4pm, 7pm, 9pm, and for adolescents, ceasing at say
11pm with bedtime remaining at 11pm thereafter. Up to 8 hours sleep
is allowed during treatment days, and provided bedtime doesn't slip
any later than the time at which treatment ceased (ie 11pm), it is
usually very successful (Horne, 1992). The obvious difficulties with
this treatment are finding somewhere quiet for daytime sleeping, and
the interference with the person's daytime activities (eg. School).
Some children presenting with free-running 25 hour sleep-wake
rhythms, can benefit from bright light treatment which blocks the
drift and resynchronises the sleep-wake rhythm (Horne, 1992).
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