A putative link between childhood narcolepsy and obesity

While there have been anecdotal observations of binge eating in childhood-onset narcolepsy, the possible relationship between increased weight gain and childhood-onset narcolepsy has not been evaluated. A retrospective, case-control design was used to compare the body mass index (BMI) of 31 narcolepsy children at the time of diagnosis with that of healthy, age- and gender-matched controls. The median BMI in the narcolepsy subjects was 22.93 as compared to that in controls of 20.36 (P=0.001). BMI did not differ significantly between narcolepsy subjects who had received prior psychotropic medications and those who had not. The mean BMI of 22 of 31 narcolepsy subjects who had not received psychotropic medications prior to diagnosis was also significantly higher than that of controls (25.1, SEM 1.53 versus 21.1, SEM 0.56; P=0.008). The tendency for increased weight gain is intrinsic to childhood narcolepsy and is manifested relatively early in the course of the disorder. Correlation of this finding with hypocretin and leptin metabolism may further understanding of the pathogenesis of narcolepsy.