Incidence rates of narcolepsy diagnoses in Taiwan, Canada, and Europe : The use of statistical simulation to evaluate methods for the rapid assessment of potential safety issues on a population level in the SOMNIA study
Dodd, Caitlin N. (Erasmus Medical Center (Rotterdam))
de Ridder, Maria A. J. (Erasmus Medical Center (Rotterdam))
Huang, Wan-Ting (Taiwan Centers for Disease Control)
Weibel, Daniel (Erasmus Medical Center (Rotterdam))
Giner-Soriano, Maria (Universitat Autònoma de Barcelona)
Perez-Vilar, Silvia (Fundación para el Fomento de la Investigación Sanitaria y Biomédica de la Comunitat (València))
Diez-Domingo, Javier (Fundación para el Fomento de la Investigación Sanitaria y Biomédica de la Comunitat (València))
Svenson, Lawrence W. (University of Alberta)
Mahmud, Salaheddin M (University of Manitoba)
Carleton, Bruce (University of British Columbia)
Naus, Monika (University of British Columbia)
Kwong, Jeffrey C. (University Health Network (Toronto))
Murray, Brian J. (Sunnybrook Health Sciences Centre (Toronto))
Arnheim-Dahlström, Lisen (Karolinska Institutet (Estocolm, Suècia). Department of Medical Epidemiology and Biostatistics)
Pedersen, Lars (Aarhus University. Department of Clinical Epidemiology)
Morros, Rosa (Universitat Autònoma de Barcelona)
Puertas, Francisco Javier (University of Valencia. Physiology Department)
Black, Steven (Cincinnati Children's Hospital Medical Center)
Sturkenboom, Miriam (University Medical Center Utrecht. Julius Center Global Health)

Date:	2018
Abstract:	Vaccine safety signals require investigation, which may be done rapidly at the population level using ecological studies, before embarking on hypothesis-testing studies. Incidence rates were used to assess a signal of narcolepsy following AS03-adjuvanted monovalent pandemic H1N1 (pH1N1) influenza vaccination among children and adolescents in Sweden and Finland in 2010. We explored the utility of ecological data to assess incidence of narcolepsy following exposure to pandemic H1N1 virus or vaccination in 10 sites that used different vaccines, adjuvants, and had varying vaccine coverage. We calculated incidence rates of diagnosed narcolepsy for periods defined by influenza virus circulation and vaccination campaign dates, and used Poisson regression to estimate incidence rate ratios (IRRs) comparing the periods during which wild-type virus circulated and after the start of vaccination campaigns vs. the period prior to pH1N1 virus circulation. We used electronic health care data from Sweden, Denmark, the United Kingdom, Canada (3 provinces), Taiwan, Netherlands, and Spain (2 regions) from 2003 to 2013. We investigated interactions between age group and adjuvant in European sites and conducted a simulation study to investigate how vaccine coverage, age, and the interval from onset to diagnosis may impact the ability to detect safety signals. Incidence rates of narcolepsy varied by age, continent, and period. Only in Taiwan and Sweden were significant time-period-by-age-group interactions observed. Associations were found for children in Taiwan (following pH1N1 virus circulation) and Sweden (following vaccination). Simulations showed that the individual-level relative risk of narcolepsy was underestimated using ecological methods comparing post- vs. pre-vaccination periods; this effect was attenuated with higher vaccine coverage and a shorter interval from disease onset to diagnosis. Ecological methods can be useful for vaccine safety assessment but the results are influenced by diagnostic delay and vaccine coverage. Because ecological methods assess risk at the population level, these methods should be treated as signal-generating methods and drawing conclusions regarding individual-level risk should be avoided.
Rights:	Aquest document està subjecte a una llicència d'ús Creative Commons. Es permet la reproducció total o parcial, la distribució, la comunicació pública de l'obra i la creació d'obres derivades, fins i tot amb finalitats comercials, sempre i quan es reconegui l'autoria de l'obra original.
Language:	Anglès
Document:	Article ; recerca ; Versió publicada
Published in:	PloS one, Vol. 13 Núm. 10 (october 2018) , ISSN 1932-6203

DOI: 10.1371/journal.pone.0204799
PMID: 30332477

15 p, 2.7 MB

The record appears in these collections:
Articles > Research articles
Articles > Published articles