A population-based study suggested that the prevalence of NA w/o CA is 36% of the prevalence of narcolepsy as a whole, corresponding to a point prevalence of 0.02%.1 NA-CA is tightly associated with HLA-DQB1*06:02 and orexin (hypocretin) deficiency. Here, HCRT is linked to hyperinsulinemic hypoglycemia, familial, 4.