Narcolepsy and Idiopathic Hypersomnia in Children Umlauf M, Makaris C, Bishop J
A retrospective chart review was conducted at the Sleep Disorder's Center at Children's Hospital in Birmingham, Alabama, looking at all children diagnosed with narcolepsy (N) and idiopathic hypersomnia (IH) between mid- 1994 to mid-2002. A total of 83 children were identified (46% N, 54% IH) with significantly more boys (65%) than girls. Children diagnosed with N were older (mean age 13.2 years) vs. IH (mean age11.5 years). During the MSLT test children with N had shorter mean sleep latencies (N: 5.1 min. vs. IH: 8.3 min.) and had a shorter REM onset (N: 3.9 min. vs. IH: 5.9). The researchers concluded that specialists were conservative when diagnosing narcolepsy over idiopathic hypersomnia in children, and that diagnoses for both conditions have increased since 1999. This reflects increasing awareness of sleep disorders among local pediatricians. It also points to the need for a valid and reliable questionnaire for quantifying excessive daytime sleepiness in children.

Body Mass Index and Narcolepsy
De Groen J, Center for Sleep and Wake Disorders, The Netherlands
Several studies have reported an increased prevalence of obesity and increased body mass indices (BMI) in narcoleptic patients. Possible causes are decreased activity due to sleepiness, or a side effect of medications taken. Recent research on hypocretin and leptin has, however, provided growing evidence that an altered energy homeostasis in narcolepsy plays a role. This study set out to explore the association of narcolepsy and BMI. Upon examination, the study of 124 newly diagnosed patients showed that BMI is increased in unmedicated narcoleptic patients, independent of age, disease duration and amount of daytime sleepiness. This underscores the notion that obesity in narcolepsy is part of the disease process itself, and not secondary to behavioral consequences of narcolepsy or medication status.

Monkey Business: What a South American Primate Can Teach Us About Narcolepsy
Ongoing research in the laboratory of Dr. Emmanuel Mignot is examining the normal role of hypocretin in maintaining wakefulness. As published in The Journal of Neuroscience and presented at the 2003 Associated Professional Sleep Societies meeting in Chicago, Dr. Jamie Zeitzer, a fellow in Dr. Mignot's laboratory, has been examining how hypocretin contributes to the maintenance of extended wakefulness in the squirrel monkey. "Besides humans, squirrel monkeys are one of the few species on the planet that consolidate wakefulness into a single daily episode," says Dr. Zeitzer. "They provide a wonderful model of the human condition and will allow us to examine how hypocretin is involved in alertness." While the complete loss of hypocretin leads to the sleep disorder narcolepsy, very little is understood about how hypocretin normally functions. Dr . Zeitzer continues, "While this avenue of research will not lead to a cure for narcolepsy, it will greatly improve our ability to treat its symptoms."

Food Consumption Patterns in Narcolepsy
Bruck D, Victoria University, Melbourne
With the discovery of hypocretin abnormalities in narcolepsy, there is increased interest in appetite and food consumption patterns in people with this sleep disorder. This study examined the detailed food, drink and medication intake patterns of 22 people with narcolepsy/cataplexy over a three-day period. The results were compared to 20 age- and socioeconomic status-matched controls. People with narcolepsy were found to initiate sweet consumption and snacking behavior more frequently than controls but did not consume more total calories or carbohydrates through snacks. Participants with narcolepsy clearly consumed more food overall than controls, with the main difference occurring at mealtime. Amongst the author's conclusions was speculation as to whether satiety signals operate normally in those with narcolepsy. Further consideration of the mechanisms (hypocretins) may explain some of the differences found, such as: appetite control abnormalities, metabolic rate differences, stressinduced eating and blood sugar irregularities (as seen with the higher rate of diabetes in narcolepsy, which has been argued to be independent of obesity).

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