Talks：

Narcolepsy and RBD

Name：

Yun Kwok Wing

Position：

Professor

Affiliation：

Department of Psychiatry The Chinese University of Hong Kong

Email：

Photo：

Research Interests：

sleep and circadian medicine, psychiatric disorders, neuropsychiatry, and transcultural psychopharmacology with extensive publications in international journals

Selected Publications：

Abstract：

Narcolepsy is a life-long disorder of central hypersomnolence. Although not being listed as a diagnostic feature in narcolepsy, symptom of REM Sleep Behavioural Disorder (RBD) has been reported to occur in nearly 50% of patients. It has been reported that RBD in narcolepsy (N-RBD) presented differently from that of idiopathic RBD (I-RBD) in terms of frequency, degree of pathology and long term prognosis. N-RBD was also found to be presented more frequently in Narcolepsy type 1 (NT1) and might help in diagnosing childhood NT1. In our study, the case notes and sleep study results of 109 patients (mean age 27.1  14.3 at baseline) diagnosed narcolepsy were analyzed, in which 65 of them had Multiple Sleep Latency Test (MSLT), Epworth Sleepiness Scale and BMI measured at both the baseline and follow up. The mean follow-up duration was 7.7  5.8 years (range 1-21 years). Fifty-five patients (50.5% of 109) had cataplexy at baseline. Six (11.1%) out of the 54 patients, who did not have cataplexy at baseline, developed cataplexy at follow up. Twenty-one (19.3% out of 109) patients presented with RBD symptoms and/or PSG documented RBD finding at baseline, which increased to 26 (40% out of 64) at follow-up, with an overall prevalence of RBD of 33.9% (37 out of 109). Patients with cataplexy (NwC) (16 out 61) had only marginally more RBD than those without cataplexy (Nw/oC) (5 out of 48) (p=0.05) at baseline. At follow up, more RBD features were reported by NwC than Nw/oC (28/61 vs 9/48, p = 0.004). On the other hand, NwC with childhood/adolescence onset (age < 16) did not present with more RBD features than Nw/oC. At baseline, RBD subjects had a significantly lower daytime MSL, while at follow up, they had a shorter nocturnal sleep latency instead. There was no difference in the other sleep parameters between those with and without RBD. More patients with cataplexy were on treatment with SSRI/SNRI antidepressants (21 vs 3) but there was no difference between those with and without RBD (13 vs 11). Seven subjects were on treatment with clonazepam with 6 of them being RBD positive.