BACKGROUND: In August 2010 reports of a possible association between exposure to AS03 adjuvanted pandemic A(H1N1)pdm09 vaccine and occurrence of narcolepsy in children and adolescents emerged in Sweden and Finland. In response to this signal, the background rates of narcolepsy in Europe were assessed to rapidly provide information for signal verification. METHODS: We used a dynamic retrospective cohort study to assess the narcolepsy diagnosis rates during the period 2000-2010 using large linked automated health care databases in six countries: Denmark, Finland, Italy, the Netherlands, Sweden and the United Kingdom. RESULTS: Overall, 2608 narcolepsy cases were identified in almost 280 million person years (PY) of follow up. The pooled incidence rate was 0.93 (95% CI: 0. 90-0.97) per 100,000 PY. There were peaks between 15 and 30 year of age (women>men) and around 60 years of age. In the age group 5-19 years olds rates were increased after the start of pandemic vaccination compared to the period before the start of campaigns, with rate ratios (RR) of 1.9 (95% CI: 1.1-3.1) in Denmark, 6.4 (95% CI: 4.2-9.7) in Finland and 7.5 (95% CI: 5.2-10.7) in Sweden. Cases verification in the Netherlands had a significant effect on the pattern of incidence over time. CONCLUSIONS: The results of this incidence study provided useful information for signal verification on a population level. The safety signal of increased narcolepsy diagnoses following the start of the pandemic vaccination campaign as observed in Sweden and Finland could be observed with this approach. An increase in narcolepsy diagnoses was not observed in other countries, where vaccination coverage was low in the affected age group, or did not follow influenza A(H1N1)pdm09 vaccination. Patient level analyses in these countries are being conducted to verify the signal in more detail.
BACKGROUND: In August 2010 reports of a possible association between exposure to AS03 adjuvanted pandemic A(H1N1)pdm09 vaccine and occurrence of narcolepsy in children and adolescents emerged in Sweden and Finland. In response to this signal, the background rates of narcolepsy in Europe were assessed to rapidly provide information for signal verification. METHODS: We used a dynamic retrospective cohort study to assess the narcolepsy diagnosis rates during the period 2000-2010 using large linked automated health care databases in six countries: Denmark, Finland, Italy, the Netherlands, Sweden and the United Kingdom. RESULTS: Overall, 2608 narcolepsy cases were identified in almost 280 million person years (PY) of follow up. The pooled incidence rate was 0.93 (95% CI: 0. 90-0.97) per 100,000 PY. There were peaks between 15 and 30 year of age (women>men) and around 60 years of age. In the age group 5-19 years olds rates were increased after the start of pandemic vaccination compared to the period before the start of campaigns, with rate ratios (RR) of 1.9 (95% CI: 1.1-3.1) in Denmark, 6.4 (95% CI: 4.2-9.7) in Finland and 7.5 (95% CI: 5.2-10.7) in Sweden. Cases verification in the Netherlands had a significant effect on the pattern of incidence over time. CONCLUSIONS: The results of this incidence study provided useful information for signal verification on a population level. The safety signal of increased narcolepsy diagnoses following the start of the pandemic vaccination campaign as observed in Sweden and Finland could be observed with this approach. An increase in narcolepsy diagnoses was not observed in other countries, where vaccination coverage was low in the affected age group, or did not follow influenza A(H1N1)pdm09 vaccination. Patient level analyses in these countries are being conducted to verify the signal in more detail.
Authors: Glenda Keating; Donald L Bliwise; Prabhjyot Saini; David B Rye; Lynn Marie Trotti Journal: Scand J Clin Lab Invest Date: 2017-05-24 Impact factor: 1.713
Authors: Mehdi Tafti; Hyun Hor; Yves Dauvilliers; Gert J Lammers; Sebastiaan Overeem; Geert Mayer; Sirous Javidi; Alex Iranzo; Joan Santamaria; Rosa Peraita-Adrados; José L Vicario; Isabelle Arnulf; Giuseppe Plazzi; Sophie Bayard; Francesca Poli; Fabio Pizza; Peter Geisler; Aleksandra Wierzbicka; Claudio L Bassetti; Johannes Mathis; Michel Lecendreux; Claire E H M Donjacour; Astrid van der Heide; Raphaël Heinzer; José Haba-Rubio; Eva Feketeova; Birgit Högl; Birgit Frauscher; Antonio Benetó; Ramin Khatami; Francesca Cañellas; Corinne Pfister; Sabine Scholz; Michel Billiard; Christian R Baumann; Guadalupe Ercilla; Willem Verduijn; Frans H J Claas; Valérie Dubois; Jacek Nowak; Hans-Peter Eberhard; Sylvain Pradervand; Charlotte N Hor; Manuela Testi; Jean-Marie Tiercy; Zoltán Kutalik Journal: Sleep Date: 2014-01-01 Impact factor: 5.849
Authors: Peter Bergman; Csaba Adori; Szilvia Vas; Ylva Kai-Larsen; Tomi Sarkanen; Andreas Cederlund; Birgitta Agerberth; Ilkka Julkunen; Beata Horvath; Diana Kostyalik; Lajos Kalmár; Gyorgy Bagdy; Anne Huutoniemi; Markku Partinen; Tomas Hökfelt Journal: Proc Natl Acad Sci U S A Date: 2014-08-18 Impact factor: 11.205