One theorized reason for the increase in epidemiological estimates is that a substantial minority of individuals with the genetic markers of WS syndrome lack the characteristic facial features or the diminished intelligence  considered to be diagnostic of the syndrome, and often are not immediately recognized as having the syndrome. History
Williams syndrome was first described by J. C. P. Williams and his colleagues, who wrote in 1961 of four patients with supravalvular aortic stenosis, mental disability, and facial features including a broad forehead, large chin, low-set, "drooping" cheeks, widely spaced eyes, and wide-set mouth. A year after this report, German physician A. J. Beuren described three new patients with the same presentation. This led to the syndromes full original name, Williams-Beuren syndrome, which is still used in some medical publications. From 1964 to 1975, small research reports broadened medical knowledge of this syndromes cardiovascular problems. Then in 1975, K. Jones and D. Smith conducted a large-scale report on numerous patients with WS, ranging in age from infancy to adulthood, and described the behavioral and observable physical symptoms in greater detail than previously recorded. Society and culture
The adjective "elfin" may have originated to describe the facial features of people with WS; before its scientific cause was understood, people believed that individuals with the syndrome, who have exceptionally charming and kind personalities, had extraordinary, even magical, powers.
Dyssomnias are a broad classification of sleeping disorders involving difficulty getting to sleep, remaining asleep, or of excessive sleepiness. Dyssomnias are primary disorders of initiating or maintaining sleep or of excessive sleepiness and are characterized by a disturbance in the amount, quality, or timing of sleep. Patients may complain of difficulty getting to sleep or staying asleep, intermittent wakefulness during the night, early morning awakening, or combinations of any of these. Transient episodes are usually of little significance. Stress, caffeine, physical discomfort, daytime napping, and early bedtimes are common factors. Types
There are over 31 recognized kinds of dyssomnias. The major three groups, along with the group types, include:: 15 Intrinsic sleep disorders: 15 
idiopathic hypersomnia,
narcolepsy,
periodic limb movement disorder,
restless legs syndrome,
obstructive sleep apnea,
central sleep apnea syndrome,
sleep state misperception,
psychophysiologic insomnia,
recurrent hypersomnia,
post-traumatic hypersomnia,
central alveolar hypoventilation syndrome,
Extrinsic sleep disorders – 13 disorders recognized, including: 16 alcohol-dependent sleep disorder,
food allergy insomnia,
inadequate sleep routine. Circadian rhythm sleep disorders, both intrinsic and extrinsic – 6 disorders recognized, including: 16 advanced sleep phase syndrome,
delayed sleep phase syndrome,
jetlag,
shift work sleep disorder. See also
Parasomnia
Sleep problems in women
Somnolence

References


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