Background: A large observational French study of central hypersomnia, including narcolepsy with cataplexy (C+), without cataplexy (C-), and idiopathic hypersomnia (IH) was conducted to clarify the relationships between severity of the condition, psychological health and treatment response.
Methods: 601 consecutive patients over 15 years of age suffering from central hypersomnia were recruited on excessive daytime sleepiness (EDS), polysomnography and Multiple Sleep Latency Test results. 517 (47.6% male, 52.4% female) were finally included: 82.0% C+, 13.2% C- and 4.8% IH. Face-to-face standardized clinical interviews plus questionnaires (Epworth Sleepiness Scale (ESS), Short-version Beck Depression Inventory (S-BDI), Pittsburgh Sleep Quality Index (PSQI) and SF-36) were performed. Patients affected with the different diagnosis, and with and without depressive symptoms were compared.
Results: Mean ESS and body mass index were higher in C+ compared to C-/IH patients. Half the patients (44.9%) had no depressive symptoms, while 26.3% had mild, 23.2% moderate and 5.6% severe depressive symptoms. C+ patients had higher S-BDI and PSQI and lower SF-36 scores than C-/IH patients. Depressed patients had higher ESS scores than non-depressed patients, with no difference for age, gender, duration of disease or MSLT parameters. Finally, C+ patients treated with anticataplectic drugs (38.7%) had higher S-BDI and lower SF-36 scores than C+ patients treated with stimulants alone.
Conclusion: Our data confirmed the high frequency of depressive symptoms and the major impact of central hypersomnias on health-related quality of life, especially in patients with cataplexy. We recommend a more thorough assessment of mood impairment in central hypersomnias, especially in narcolepsy-cataplexy.