Gender differences in narcolepsy: What are recent findings telling us?

Three papers currently published in SLEEP using two different mouse models of narcolepsy, including either Hcrt-tTa;TetO diptheria toxin-A (DTA) or Hypocretin knock-out (Hcrt-KO) mice, suggest important gender differences in narcolepsy expression. Specifically, these recent data corroborate previous findings in mice demonstrating that females show more cataplexy events and more total cataplexy expression than males. Moreover, in the neurotoxic DTA mouse model, females show earlier onset of cataplexy expression than males during active Hcrt cell loss. Finally, females show a doubling of cataplexy during estrous compared to other phases of the estrous cycle. These findings are reviewed in the broader context of prior published literature, including reported gender differences in Hcrt expression and hormonal influences on sleep and wakefulness. Although similar findings have not been reported in humans, a systematic evaluation of gender differences in human narcolepsy has yet to be performed. Taken together, these animal data suggest that more research exploring gender differences in human narcolepsy is warranted.

Automated summary

Three papers published in SLEEP using different mouse models of narcolepsy indicate significant gender differences in the expression of narcolepsy symptoms. Female mice exhibit more cataplexy events and greater overall cataplexy expression compared to males. Additionally, female mice in the neurotoxic DTA mouse model experience cataplexy symptoms earlier than males during the loss of Hcrt cells. Furthermore, the occurrence of cataplexy is twice as frequent during the estrous phase in females. These findings highlight the need for further research on gender differences in human narcolepsy.