Sleep disorders in children.

about 200 times more frequently in such patients than in the general population.'416 Niederau et al found that patients receiving treatment before cirrhosis appeared did not develop hepatocellular carcinoma later.'4 The case is, therefore, convincing. Individual people with the genetic predisposition to develop hereditary haemochromatosis seem to be relatively common (at least in white populations), and early venesection treatment prevents progression of hepatic disease to cirrhosis and may consequently prevent the complication of hepato-cellular carcinoma. We should therefore aim at diagnosing hereditary haemochromatosis as early as possible, and screening for this condition would probably benefit more patients than many tests done routinely on blood taken from patients in hospital. they also have hereditary spherocytosis. causes of death in cirrhotic and in non-cirrhotic patients with primary hemochromatosis. These problems are underrecognised and undertreated Over the past 10 to 15 years the specialty of sleep disorders medicine has become very popular (and commercially successful) in North America, where many sleep disorders centres now exist. The European Sleep Society was founded in 1972, and the British Sleep Society was established just last year. These developments, however, have been concerned overwhelmingly with sleep disorders in adults. Of the 450 papers presented at the annual meeting of the Association of Professional Sleep Societies in the United States last year just 18 concerned children and a further seven were about adolescents. Medical textbooks underestimate the range of sleep disorders. The official classification of sleep and arousal disorders has as its main categories insomnias, causes of daytime sleepiness, disorders of the sleep/wake cycle, and episodic disorders occurring in or made worse by sleep (parasomnias).' Additional problems encountered particularly in children include bedtime fears and bed wetting. The phrase "sleep disorder" implies a problem to the child or the parents; sleep behaviours-such as snoring, head banging, teeth grinding, or restless sleep-do not necessarily constitute a problem, though they might be part of a disorder. Sleep disorders in children may be clinically important in various ways. Chronic lack of sleep will affect the daytime behaviour and performance of the child-and often of other members of the family. This problem seems to be particularly common in mentally handicapped children.2 Parasomnias are often frightening and the cause of much concern to parents. They may also be a source of diagnostic confusion: non-epileptic parasomnias may be misdiagnosed as epilepsy, and non-convulsive forms of epilepsy in particular are sometimes misconstrued as "nightmares."3 Sleep …