Charakterisierung von Früh- und Spätmanifestationen bei Narkolepsie

Introduction: Recent studies in European and Canadian narcoleptics confirmed two peaks in the age of onset. We were interested to investigate the differences between the two groups. Methods: A prospective study in 136 consecutive patients (63 males, 73 females, age 13-78) was performed using a German nacolepsy questionaire (51 questions on demographics, symptoms, co-morbidity), nocturnal polysomnography (NPSG), Multiple Sleep latency Test (MSLT, both n=90) and Epworth Sleepiness Scale (ESS, n=84). Staistical analysis was performed with the Mann-Whitney-U-Test. Results: Age at symptom onset has a major peak at 16.6 years (group1, n=105), a second peak at 40.1 years (group2, n=31). The age separating both groups is 30 years. Women have first symptoms significantly earlier than men (p=0.015). In the majority of both groups excessive daytime sleepiness is the first symptom. Mean latency between the first symptom and sleep attacks is 1.5 years in group1, 0.6 years in group2. The latency between the first symptom and cataplexy is 6.3 years in group1, 1,7 years in group2. Men in group2 suffer more often from sleep apnea, diabetes and hypertension. Mean sleep latency in the MSLT is shorter in group1 (p=0.007) and number of sleep onset REM periods is higher (p=0.043) than in group2. In the NPSG wake after sleep onset in group1 is shorter (p=0.045) than in group2. No significant differences were found for ESS score, total sleep time, sleep latency, sleep efficiency and REM latency. Conclusion: Patients with early and late onset of narcolepsy are distinctly different in clinical and polysomnographic features. The results evidence the existence of two different narcolepsy phenotypes. The whole array of narcoleptic symptoms starts much earlier in patients with late onset, whereas. their NREM and REM sleep propensity seems to be higher. Future studies will focus on pathophysiological differences of the two groups.