Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2020 Dec 8;95(23):e3117-e3123.
doi: 10.1212/WNL.0000000000010911. Epub 2020 Sep 17.

Unverricht-Lundborg disease (EPM1) in Finland: A nationwide population-based study

Jussi O T Sipilä  1 , Jelena Hyppönen  2 , Ville Kytö  2 , Reetta Kälviäinen  2
Affiliations

Unverricht-Lundborg disease (EPM1) in Finland: A nationwide population-based study

Jussi O T Sipilä et al. Neurology. .

Abstract

Objective: To investigate the epidemiology and prognosis of Unverricht-Lundborg disease (EPM1) in a nationwide, population-based setting.

Methods: Data from multiple registries were combined and analyzed. Clinical data were obtained from medical records. All patients treated for EPM1 in Finland between January 1, 1998, and December 31, 2016 were included.

Results: A total of 135 persons with EPM1 (54% women) were identified and 105 were alive on December 31, 2016 (point prevalence 1.91/100,000 persons). The age-standardized (European Standard Population 2013) prevalence was 1.53/100,000 persons. Annual incidence during the study period was 0.022/100,000 person-years, with a mean age at onset of 9.4 ± 2.3 years (range 7.0-14.6 years, no sex difference). The median age at death (n = 34) was 53.9 years (interquartile range 46.4, 60.3; range 23.2-63.8), with no sex differences. The immediate cause of death was a lower respiratory tract infection in 56% of deaths. The survival rates of the patients were comparable to matched controls up to 40 years of age, but poorer during long-term follow-up (cumulative survival 26.4% vs 78.0%), with a hazard ratio (HR) for death of 4.61. The risk of death decreased with increasing age at onset (HR 0.76 per year, 95% confidence interval 0.65-0.89). In approximately 10% of all cases, the disease progression appeared very mild; some patients retained functional independence for decades.

Conclusions: Unverricht-Lundborg disease is rare in Finland but still more common than anywhere else in the world. The disease course appears somewhat more severe than elsewhere, disability mounts early, and death occurs prematurely.

PubMed Disclaimer

Figures

Figure 1
Figure 1. Age-related characteristics of Unverricht-Lundborg disease in Finland
(A) Age at symptom onset in 125 patients. (B) Age-specific prevalence on December 31, 2016.
Figure 2
Figure 2. Cumulative survival from birth in 135 Finnish patients with Unverricht-Lundborg disease and 27,000 matched controls
Figure 3
Figure 3. Functional status of patients diagnosed in 1998–2016 on December 31, 2016
(A) Ambulation. (B) Domicile.
Figure 4
Figure 4. Ratio of Unverricht-Lundborg disease diagnoses (data available for 98) to the proportion of general population by area
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Kälviäinen R, Khyuppenen J, Koskenkorva P, Eriksson K, Vanninen R, Mervaala E. Clinical picture of EPM1-Unverricht-Lundborg disease. Epilepsia 2008;49:549–556. - PubMed
    1. Hyppönen J, Äikiä M, Joensuu T, et al. . Refining the phenotype of Unverricht-Lundborg disease (EPM1) a population-wide Finnish study. Neurology 2015;84:1529–1536. - PubMed
    1. Canafoglia L, Ferlazzo E, Michelucci R, et al. . Variable course of Unverricht-Lundborg disease early prognostic factors. Neurology 2017;89:1691–1697. - PubMed
    1. de Haan GJ, Halley DJ, Doelman JC, et al. . Unverricht-Lundborg disease: underdiagnosed in The Netherlands. Epilepsia 2004;45:1061–1063. - PubMed
    1. Norio R, Koskiniemi M. Progressive myoclonus epilepsy: genetic and nosological aspects with special reference to 107 Finnish patients. Clin Genet 1979;15:382–398. - PubMed

Publication types

MeSH terms