Patients with narcolepsy in Slovenia
Background: To determine the number of patients with narcolepsy in Slovenia, describe their typical clinical features and the diagnostic criteria they met on polysomnography (PSG), the mean sleep latency test (MSLT) and HLA typing.
Methods: Retrospective study of all narcolepsy patients referred to the National Sleep Disorder Centre at the Institute of Clinical Neurophysiology, University Medical Centre Ljubljana in the period from May 1994 to September 2013.
Results: There are currently only 38 patients with narcolepsy in Slovenia. The average time lapse from onset to diagnosis is 17 years. The time lapse is much longer for older patients. The prevalence of narcolepsy in Slovenia is 1.85 to 100,000 inhabitants. All patients had EDS, 89% cataplexy, 66% hallucinations and 37% sleep paralysis at the time of diagnosis. Characteristic changes on PSG and MSLT were present in 97% of all tested patients. HLA DQB1*0602 is present in 88% of all tested patients. The most common differential diagnoses found were OSAS and hypersomnia.
Conclusion: With a prevalence of 1.85/100,000 narcolepsy in Slovenia, it is seriously underdiagnosed and not recognized by general practitioners and neurologists alike. Both should be more aware of the disease and think about the possibility of it in patients with excessive daytime sleepiness and unexplained attacks, with additional symptoms such as hallucinations and paralysis during sleep. Such patients should be sent to the Sleep Disorder Centre, where the diagnosis can be confirmed and treatment started as soon as possible, thereby reducing the patient’s pathological symptoms and improve their quality of life.
Longstreth W, Koepsell T, Ton T, et al. The epidemiology of narcolepsy. Sleep 2007;30:13-26
Silber M, Krahn L, Olson E, et al. The epidemiology of narcolepsy in Olmsted County, Minnesota: a population based study. Sleep 2002;25:197-202
Overeem S, Mignot E, van Dijk JG, Lammers GJ. Nercolepsy: clinical features, new pathophysiologic insights, and future perspectives. J Clin Neurophysiol. 2001;18(2):78-105
Kryger MH, Walid R, Manfreda J. Diagnoses received by narcolepsy patients in the year prior to diagnosis by a sleep specialist. Sleep. 2002;25(1):36-41.
American Academy of Sleep Medicine. International classifications of sleep disorders, diagnostic and coding manuel. 2nd edition. Westchester (IL): American academy of Sleep Medicine; 2005
Mignot E, Lammers G, Ripley B, et al. The role of cerebrospinal fluid hypocretin measurement in the diagnosis of narcolepsy and other hypersomnias. Arch Neurol 2002;59:1553:62
Harris S, Monderer R, Thorpy M. Hypersomnias of Central Origin. Neurol Clin 30 (2012) 1027-1044
Black J, Houghton WC. Sodium oxybate improves exsessive daytime sleepiness in narcolepsy. Sleep 2006;23:939-46
Mamelak M, Scharf MD, Woods M. Treatment of narcolepsy with gamma-hydroxybutyrate. A review of clinical and sleep laboratory findings. Sleep 1986;9:285-9
Lammers GJ, Bassetti C, Billard M, et al. Sodium oxybate is an effective and safe treatment for narcolepsy. Sleep Med 2010;11:105-6
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