Daytime sleepiness with and without cataplexy in Chinese-Taiwanese patients.
OBJECTIVE
Investigation of Chinese-Taiwanese patients with excessive sleepiness, but no association with other sleep disorders, and with the presence or absence of cataplexy.


METHODS
Thirty-five patients, successively referred between 2002 and 2004, underwent polysomnography (PSG), repeat multiple sleep latency test (MSLT), and human leukocyte antigen (HLA) typing. Three patients without cataplexy also had cerebrospinal fluid (CSF) hypocretin measurements.


RESULTS
DQB1*0602 was associated with cataplexy in over 90% of Chinese-Taiwanese cases. Absence of cataplexy and <2 sleep-onset REM periods (SOREMPs) was seen in only two subjects, but presence of two SOREMPs did not dissociate DQB1*0602 positive and negative or cataplexy positive and negative subjects. As a group, narcoleptics with cataplexy had a higher number of SOREMPs, and the mean sleep latency was much shorter in narcoleptics with cataplexy than in the non-cataplectic patients, independent of the number of SOREMPs.


CONCLUSIONS
Chinese-Taiwanese patients with cataplexy present with similar HLA findings as Black and Caucasian patients, but the presence of two or more SOREMPs in Chinese-Taiwanese patients is not a sufficient diagnostic tool to identify narcolepsy. When cataplexy is not present, description of PSG nd HLA findings may be a better approach than using a label with little scientific significance, allowing for better collection of patients' phenotype.
Huang
Yu-shu
YS
Sleep Disorders Clinic, Chang-Gung University Hospital, Taipei, Taiwan, ROC.
Tafti
Mehdi
M
Guilleminault
Christian
C
D000293:Adolescent; D000328:Adult; D044466:Asian People / Q000235:genetics*; D015415:Biomarkers / Q000097:blood / Q000134:cerebrospinal fluid; D002385:Cataplexy / Q000208:ethnology / Q000503:physiopathology; D005260:Female; D006683:HLA-DQ Antigens / Q000097:blood*; D059866:HLA-DQ beta-Chains; D006650:Histocompatibility Testing; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000134:cerebrospinal fluid; D008297:Male; D008562:Membrane Glycoproteins / Q000097:blood*; D009290:Narcolepsy / Q000175:diagnosis / Q000208:ethnology* / Q000503:physiopathology; D009479:Neuropeptides / Q000134:cerebrospinal fluid; D000068797:Orexins; D010641:Phenotype; D017286:Polysomnography; D012895:Sleep, REM; D013624:Taiwan / Q000453:epidemiology
D015415:Biomarkers; D006683:HLA-DQ Antigens; D059866:HLA-DQ beta-Chains; C069051:HLA-DQB1 antigen; D047908:Intracellular Signaling Peptides and Proteins; D008562:Membrane Glycoproteins; D009479:Neuropeptides; D000068797:Orexins