SLEEP DISORDERS

Sleep pattern of a child depends on the age, behavioral pattern, frequency/duration of daytime naps and environment during bedtime. A newborn sleeps for gt;20 hours/day, which is gradually reduced to 8 hours by the end of first year.

Biological temperament and emotional stress, e.g. separation anxiety, home/school fears, insecurity, etc. are most important causes of sleep problems in childhood, though important organic causes include (a) obstructive sleep apnea syndrome, (b) organic brain disorders, e.g. attention-deficit disorder or autism, (c) other, e.g. Prader- Willi syndrome.

Common sleep disorders include: (a) insomnia or interrupted sleep, (b) hypersomnia or narcolepsy, and

(c) parasomnias, e.g. somnambulism (sleep-walking), nightmares or night terrors.

Parasomnia refer to abnormal behavior or motor manifestations during sleep and include:

• Parasomnias during early NREM sleep, presenting with sleep walking (awake and ambulatory), con- fusional arousals (awake but not ambulatory) and night terrors.

• Parasomnias during late REM sleep include night mares and bizarre movements/behavior.

All these conditions are self-limiting and no specific treatment is required except reassurance.

Night-terrors are commonest sleep problems in pre-school children, characterized by sudden arousal from sleep in disoriented state with screaming and signs of intense autonomic activity, e.g. labored breathing, tachycardia, sweating and dilated pupils. Some children may sleep­walk (somnambulism) for few minutes, before getting oriented or going back to sleep. History of a bad dream (nightmare) is often present. Though occasional attacks are common, recurrent night terrors indicate significant underlying phobia, anxiety or emotional trauma.

Narcolepsy is rare, characterized by excessive daytime sleepiness, cataplexy, sleep paralysis, hypnagogic hallucinations and poor school performance.

It is also considered as a paroxysmal disorder or seizure mimics, with attacks of irrepressible sleep attacks during day time, from which the patient is easily arousable (d/d absence seizures). EEG reveals intermittent attacks of REM sleep. Modafinil acetamide (PO 200 mg OD) is drug of choice in confirmed cases.

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