The majority of patients with narcolepsy with cataplexy experience a number of symptoms of eating disorders, with an irresistible craving for food and binge eating as the most prominent features, according to a study published in the March 1 Sleep.
Hal Droogleever Fortuyn, MD, and colleagues focused on 60 patients with narcolepsy with cataplexy who were recruited from specialized sleep centers, 23.3% of whom fulfilled the criteria for a clinical eating disorder using the Schedules for Clinical Assessment in Neuropsychiatry. None of the 120 control subjects fulfilled criteria for an eating disorder. Most patients with narcolepsy with cataplexy who had an eating disorder were classified as Eating Disorder Not Otherwise Specified, with an incomplete form of binge-eating disorder. Half the patients reported a persistent craving for food, as well as binge eating, and 25% reported binging at least twice a week.
"These data make it clear that narcolepsy is not just a sleeping disorder but a hypothalamic disease with a much broader symptom profile," said Dr. Fortuyn, a psychiatrist at Radboud University Nijmegen Medical Center in the Netherlands.
"Hypocretin, the neurotransmitter that is lost in narcolepsy, has been implicated in the regulation of feeding through animal studies," Dr. Fortuyn continued. "Earlier studies in narcolepsy found a clear increase in body weight. However, we did not find a correlation between binge eating and increased weight.
"Binge eating is apparently not the direct cause of the obesity in narcolepsy, and this suggests that metabolic alterations may be involved," concluded Dr. Fortuyn. "Nevertheless, our study shows that the loss of hypocretin function not only makes narcolepsy patients struggle to stay awake but also destabilizes their eating patterns, which makes it harder to stay away from the candy jar."