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.
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