SLEEPWALKING (somnambulism) is not uncommon among children and is a reason for a medical consulataion. The children find themselves in a state of transition from one sleep cycle to the next, non-rapid eye movement (NREM), to wakefulness.
During this transition state, there is a high arousal threshold, mental confusion and unclear perception.
It usually occurs in the first or second sleep cycle during the deeper stages of NREM sleep.
When the child awakens there is no recollection of the sleepwalking. It is sometimes associated with nonsensical talking. The child’s eyes are often open with a characteristic “looking right through you” appearance.
As somnambulism occurs more often in children, there are suggestions that it is indicative of immaturity of the central nervous system.
It is estimated to occur in about 15% of children aged between four and 12. Somnambulism can sometimes start in their teens but is usually resolved by the late teenage years. However, it also occurs in adults.
Some children may hit objects while sleepwalking and injure themselves occasionally. The effects in adolescents and adults may be of more concern as there have been reports of behaviours like driving a car, cooking and eating, with consequent injuries.
There are several causes of sleepwalking. It is more common in identical twins and is 10 times more likely to occur if a first degree relative also sleepwalks.
In adults, the frequency of sleepwalking increases during menstruation and pregnancy. Sleepwalking may be triggered by disordered sleep schedules, sleep deprivation, fever, stress and excessive alcohol consumption.
Certain medicines can cause sleepwalking. They include sleeping pills (hypnotics), allergy pills (antihistamines), antidepressants, some antibiotics (fluoroquinolone) and calming pills (tranquilisers).
Sleepwalking is associated with medical conditions like fever, nocturnal asthma or fits, abnormal heart rhythms (arrhythmias), regurgitation of food from the stomach into the oesophagus (reflux), psychiatric conditions (panic attacks and post-traumatic stress) and when there is temporary stoppage of breathing during sleep (obstructive sleep apnoea).
Somnambulism episodes vary and can range from walking quietly around a room to disturbed running. The patients may later tell of attempts to run away from dangerous situations. They have a typical clumsy, staring and dazed appearance with their eyes opened as they walk about.
When questioned, their responses are slow or absent with simple or nonsensical words uttered. There is no recollection of the event if the person returns to bed without awakening. Older children are more likely to be awakened at the end of the episode of somnambulism.
Somnambulism has to be distinguished from night terrors (or sleep terrors) which are similar to somnambulism in that they occur in the first or second sleep cycle during the deeper stages of NREM sleep.
However, night terrors present with sudden screams associated with a panic-like appearance. The eyes are opened wide, there is sweating and increased heart and respiratory rates. This may be followed by movements such as running around the room.
By itself, night terrors are not dangerous but injuries to the child or others may result if the child is violent. Night terrors may occur for many consecutive weeks, stop completely and then recur later. They usually cease when the child reaches adolescence but may occasionally persist until the child is mature.
A similar condition is confusional arousals. They occur in the first or second sleep cycle during the deeper stages of NREM sleep. There are short episodes, lasting about 10 minutes or so, of disorientation, inconsolable crying and thrashing movements in bed.
The child typically does not remember the event. The condition is common in younger children. Attempts to awaken the child frequently prolong the episode.
However, if the child is awakened, the episode typically ceases. Unlike night terrors, there are no changes like sweating and increased heart and respiratory rates.
Diagnosis and management
No treatment is needed in most instances of somnambulism because it is rarely an indication of a medical or psychiatric problem.
Somnambulism usually disappears in most children at puberty although it sometimes persist into adulthood. A medical consultation is advisable if it occurs frequently, if there is injury or if the behaviour is violent.
The doctor will carry out a physical examination to exclude any medical causes. Sometimes, a specialist referral may be made for an assessment to determine whether a psychiatric condition is the cause.
Reassurance is all that is needed in most instances. Several general measures can be taken by someone affected by somnambulism which includes getting sufficient sleep and avoiding any precipitating factors like visual, tactile or auditory stimuli just before bedtime.
To reduce the likelihood of injury, remove obstacles and sharp objects from the bedroom and avoid bunk beds. Lock windows and doors of the bedroom. It may be useful to have an alarm placed on the window or door.
Any underlying medical condition such as fever, nocturnal asthma or fits, cardiac arrhythmias, obstructive sleep apnoea, gastro-oesophageal reflux, panic attacks or post-traumatic stress, would be treated appropriately.
Medicines are prescribed if there is a likelihood of injury, excessive sleepiness during the day, significant disruption of family life, and general measures have been unhelpful.
The medicines that have been reported to be useful are the benzodiazepines, tricyclic antidepressants and serotonin reuptake inhibitors. Low-dose clonazepam before going to bed for three to six weeks have also been reported to be usually effective.
The medicines can be stopped after three to six weeks without recurrence of symptoms.
Other treatment like relaxation techniques and anticipatory awakenings have been reported to be useful.
These techniques are usually carried out by a psychologist. Anticipatory awakenings involve waking up the affected child about 15 minutes prior to the usual time the somnambulism occurs and keeping the child awake throughout the time the episode usually occur.
Somnambulism can be prevented by avoiding sleep deprivation, avoiding stress and avoiding alcohol consumption.
Source: Dr Milton Lum