title: Estimation of background incidence rates of Guillain-Barré syndrome in Germany - a retrospective cohort study with electronic healthcare data.
abstract: BACKGROUND
  The Guillain-Barré syndrome (GBS) occurs after infections and as an adverse reaction to vaccines. No detailed information on incidence rates (IRs) in Germany is available.
  
  
  METHODS
  This retrospective cohort study estimated age- and sex-specific IRs of GBS in Germany in the years 2007-2009 based on electronic healthcare data from the German Pharmacoepidemiological Research Database (GePaRD). Two case definitions were applied. GBS cases had a main discharge diagnosis of GBS. GBS_PROCEDURE cases in addition had codes for relevant diagnostic procedures. Crude and standardized IRs (SIRs) with 95% confidence intervals were stratified by year, age group, sex, region and season. IR ratios (IRRs) for each stratification factor were calculated by multivariable Poisson regression.
  
  
  RESULTS
  Among 13,297,678 persons, 889 (693) incident GBS (GBS_PROCEDURE) cases were identified. Overall SIRs per 100,000 person years were 2.4 (2.2-2.5) for GBS and 1.8 (1.7-2.0) for GBS_PROCEDURE. (S)IRs increased with age, peaking in the age group 70-79 years (IR GBS: 5.5 (4.7-6.5)) and were higher in males than in females (e.g., IR GBS: IRR = 1.5 (1.3-1.7)) and in February-April, as compared to the rest of the year. No regional pattern was observed.
  
  
  CONCLUSIONS
  (S)IRs of GBS in Germany differed by age, sex and season and were comparable to those found in other studies. RESULTS might be used as a comparator in vaccine safety monitoring.
authors.affiliation: Clinical Epidemiology, Leibniz Institute for Prevention Research and Epidemiology - BIPS GmbH, Bremen, Germany.
authors.forename: Sabrina
authors.initials: S
authors.lastname: Hense
authors.forename: Tania
authors.initials: T
authors.lastname: Schink
authors.forename: Stefan H
authors.initials: SH
authors.lastname: Kreisel
authors.forename: Lydie
authors.initials: L
authors.lastname: Marcelon
authors.forename: François
authors.initials: F
authors.lastname: Simondon
authors.forename: Maike
authors.initials: M
authors.lastname: Tahden
authors.forename: Edeltraut
authors.initials: E
authors.lastname: Garbe
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D057286:Electronic Health Records; D005260:Female; D005858:Germany / Q000453:epidemiology; D020275:Guillain-Barre Syndrome / Q000453:epidemiology*; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012621:Seasons; D012737:Sex Factors; D055815:Young Adult