Sleep difficulties in children and adolescents
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).
Overview of Parasomnias
Sleep Terror Disorder
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)
- 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 disorde
- 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)
common; 10 and 15% of children are affected.
especially between the ages of three and six
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).
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
- environmental factors (Wicks-Nelson & Israel, 1997).
(2) SLEEPWALKING (connected to slow wave sleep)
- 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
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).
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.
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)
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).
- 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)
- 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;
- 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).
- 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);
- occurs between the ages of 4 and 12;
- episode: during SWS and at a constant time = 2 hours into sleep;
- 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).
- 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)
The 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).
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 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.
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 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.
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).
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.
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 Sleep
Behavioural 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).
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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