Night terrors

GENERAL ASPECTS

Night terrors are parasomnias, i.e., sleep disorders characterized by physical phenomena or undesirable or annoying behaviors that occur predominantly or exclusively during sleep. Many of them are manifested by abnormal muscle activity and/or changes in the autonomic nervous system.

DEFINITIONS

Sleep terrors are characterized by a rude awakening from deep sleep, during the first third of the night, accompanied by an autonomic and behavioral response of intense fear. The child is very agitated, frightened and confused, screaming or crying, with autonomic symptoms (hyperventilation, tachycardia, sweating and pupillary dilation), and there may be a behavioral and ambulation disorder and even injury. The episode lasts a few minutes and ends spontaneously with the child going back to sleep. As in sleepwalking, the child does not respond to external stimuli and does not usually remember the episode upon awakening in the morning.

PREVALENCE

Night terrors are less frequent than sleepwalking, although sometimes associated with it. Their prevalence is estimated between 1% and 5% in school-age children and is typical between 3 and 4 years of age, although sometimes they are reproduced between 5 and 6 years of age. The frequency of episodes is maximal as soon as the process begins. Before the age of 4 years they tend to appear more frequently (at least once a week); thereafter, they are less frequent. The average duration of the process is usually about 4 years with a tendency to a longer duration in those children who have a family history of sleepwalking. Fifty percent of cases usually disappear by the age of 8 years but 36% continue into adolescence.

DIAGNOSTIC CRITERIA

According to the American Academy of Sleep Medicine, they are characterized by the following diagnostic criteria:

1. Sudden episode of terror during sleep, which begins with a loud scream or cry and is accompanied by manifestations of intense fear of the autonomic nervous system and behavior.
2. At least one of the following:

• Difficulty in awakening the person
• Mental confusion when waking up after an episode
• Amnesia (total or partial) of the episode
• Dangerous or potentially dangerous behavior

1. The disorder cannot be better explained by the presence of another sleep disorder, medical illness or neurological disorder, medication use or use of other substances

EVOLUTION

Sleep terrors are usually benign, self-limited phenomena that tend to disappear with time and do not require specific treatment except when they are very persistent.