Prevalence of narcolepsy with cataplexy in Norway.
OBJECTIVE
Narcolepsy is a lifelong disabling disorder that may be alleviated by relevant treatment. Patients frequently report 10-15 years from the first symptoms to the time they get the diagnosis and treatment can be started. In order to offer a sufficient diagnostic and therapeutic service to this patient group, a reliable estimation of the prevalence of the disorder is important. A study of the prevalence of narcolepsy with cataplexy in Norway was therefore undertaken.


METHODS
The Ullanlinna Narcolepsy scale (UNS) was sent to 14548 randomly selected Norwegians between 20 and 60 years. Additionally, the study included telephone interviews and clinical evaluation of responders with >or=14 points on the UNS, and in those with suspected narcolepsy, polygraphic sleep recordings and human leucocyte antigen (HLA)-typing.


RESULTS
A total of 8992 responders answered the questionnaire (response rate 61.8%), 267 had >or=14 points on the UNS, 156 were interviewed and 15 had sleep recordings. In two HLADQB1*0602-positive patients sleep recordings were compatible with narcolepsy.


CONCLUSIONS
The results indicate a prevalence of 0.022% and approximately 1000 patients with narcolepsy with cataplexy in Norway.
Heier
M S
MS
Norwegian Resource Center for AD/HD, Tourettes Syndrome and Narcolepsy, Ullevål University Hospital, Oslo, Norway. msheier@online.no
Evsiukova
T
T
Wilson
J
J
Abdelnoor
M
M
Hublin
C
C
Ervik
S
S
D000328:Adult; D002385:Cataplexy / Q000150:complications* / Q000453:epidemiology* / Q000235:genetics; D005260:Female; D020022:Genetic Predisposition to Disease; D006683:HLA-DQ Antigens / Q000235:genetics; D059866:HLA-DQ beta-Chains; D006801:Humans; D008297:Male; D008562:Membrane Glycoproteins / Q000235:genetics; D008875:Middle Aged; D009290:Narcolepsy / Q000150:complications* / Q000453:epidemiology* / Q000235:genetics; D009664:Norway / Q000453:epidemiology; D015995:Prevalence; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires; D055815:Young Adult
D006683:HLA-DQ Antigens; D059866:HLA-DQ beta-Chains; C069051:HLA-DQB1 antigen; D008562:Membrane Glycoproteins