Idiopathic hypersomnia: a study of 77 cases.

STUDY OBJECTIVES To review the clinical and polysomnographic characteristics of idiopathic hypersomnia as well as the long-term response to treatment. SETTING The Respiratory Support and Sleep Centre at Papworth Hospital, Cambridge, UK. PATIENTS AND DESIGN A large database of more than 6000 patients with sleep disorders was reviewed. A retrospective study of the clinical and polysomnographic characteristics of 77 patients with idiopathic hypersomnia was performed. Comparison with a similar group of patients with narcolepsy was performed. The response to drug treatment was assessed in 61 patients over a mean follow-up of 3.8 years. MEASUREMENTS AND RESULTS Idiopathic hypersomnia was 60% as prevalent as narcolepsy. Comparison with a similar group of patients with narcolepsy showed that those with idiopathic hypersomnia were more likely to have prolonged unrefreshing daytime naps, a positive family history, increased slow-wave sleep, and a longer sleep latency on the Multiple Sleep Latency Test. The results of the Multiple Sleep Latency Test were not helpful in predicting disease severity or treatment response. The clinical features were heterogeneous and of variable severity. The majority of patients with idiopathic hypersomnia had symptoms that remained stable over many years, but 11% had spontaneous remission, which was never seen in narcolepsy. Two thirds of patients with idiopathic hypersomnolence had a sustained improvement in daytime somnolence with medication, although a third needed high doses or combinations of drugs. CONCLUSIONS Idiopathic hypersomnolence has characteristic clinical and polysomnographic features but the prolonged latency on the Multiple Sleep Latency Test raises doubt about the validity of this test within the current diagnostic criteria. The disease often responds well to treatment and a substantial minority of patients appear to spontaneously improve.

[1]  T. Young,et al.  Correlates of sleep-onset REM periods during the Multiple Sleep Latency Test in community adults. , 2006, Brain : a journal of neurology.

[2]  Kiyohisa Takahashi,et al.  Difference in the characteristics of subjective and objective sleepiness between narcolepsy and essential hypersomnia , 2005, Psychiatry and clinical neurosciences.

[3]  C. Guilleminault,et al.  Meta-analysis of quantitative sleep parameters from childhood to old age in healthy individuals: developing normative sleep values across the human lifespan. , 2004, Sleep.

[4]  S. Meunier,et al.  Study of a patient population investigated for excessive daytime sleepiness (EDS) , 2002, Neurophysiologie Clinique/Clinical Neurophysiology.

[5]  Y. Dauvilliers,et al.  Response to "Idiopathic hypersomnia: a diagnostic dilemma" (J. Montplaisir and L. Fantini). , 2001, Sleep medicine reviews.

[6]  H. Moldofsky,et al.  Randomized, double-blind, placebo-controlled crossover trial of modafinil in the treatment of excessive daytime sleepiness in narcolepsy , 1997, Neurology.

[7]  M. Aldrich,et al.  Idiopathic hypersomnia : A series of 42 patients , 1997 .

[8]  R. Chervin,et al.  Comparison of the results of the Epworth Sleepiness Scale and the Multiple Sleep Latency Test. , 1997, Journal of psychosomatic research.

[9]  M. Aldrich.  The clinical spectrum of narcolepsy and idiopathic hypersomnia , 1996, Neurology.

[10]  T. Roth,et al.  The reliability of the diagnostic features in patients with narcolepsy , 1996, Biological Psychiatry.

[11]  M. Johns,et al.  Sleepiness in different situations measured by the Epworth Sleepiness Scale. , 1994, Sleep.

[12]  S Koskimies,et al.  The prevalence of narcolepsy: An epidemiological study of the Finnish Twin Cohort , 1994, Annals of neurology.

[13]  M. Carskadon,et al.  Guidelines for the multiple sleep latency test (MSLT): a standard measure of sleepiness. , 1986, Sleep.

[14]  D J Kupfer,et al.  Sleep-wake disorders based on a polysomnographic diagnosis. A national cooperative study. , 1982, JAMA.

[15]  H. Kraemer,et al.  Disorders of excessive daytime somnolence: polygraphic and clinical data for 100 patients. , 1981, Sleep.

[16]  G. Vogel.  Studies in psychophysiology of dreams. III. The dream of narcolepsy. , 1960, Archives of general psychiatry.

[17]  W. J. Adie.  IDIOPATHIC NARCOLEPSY: A DISEASE SUI GENERIS; WITH REMARKS ON THE MECHANISM OF SLEEP , 1926 .

[18]  C. Guilleminault,et al.  Comparative polysomnographic study of narcolepsy and idiopathic central nervous system hypersomnia. , 1986, Sleep.

[19]  J. Montplaisir,et al.  HLA antigens in narcolepsy and idiopathic central nervous system hypersomnolence. , 1986, Sleep.

[20]  B. Roth.  Narcolepsy and hypersomnia: review and classification of 642 personally observed cases. , 1976, Schweizer Archiv fur Neurologie, Neurochirurgie und Psychiatrie = Archives suisses de neurologie, neurochirurgie et de psychiatrie.