Estimation of Background Incidence Rates of Guillain-Barré Syndrome in Germany in the years 2007-2009 (BIGS)

Study type

• Study topic:
  Disease /health condition
• Study type:
  Non-interventional study
• Scope of the study:
  Disease epidemiology
• Data collection methods:
  Secondary use of data

Non-interventional study

• Non-interventional study design:
  Cohort

Study drug and medical condition

• Medical condition to be studied:
  Guillain-Barre syndrome

Population studied

• Short description of the study population:
  Residents of Germany.
• Age groups:
  Preterm newborn infants (0 – 27 days)

  Term newborn infants (0 – 27 days)

  Infants and toddlers (28 days – 23 months)

  Children (2 to < 12 years)

  Adolescents (12 to < 18 years)

  Adults (18 to < 46 years)

  Adults (46 to < 65 years)

  Adults (65 to < 75 years)

  Adults (75 to < 85 years)

  Adults (85 years and over)
• Estimated number of subjects:
  13297678

Study design details

• Main study objective:
  The main objective of this study was to estimate the background incidence of GBS in Germany in the years 2007 to 2009. A focus was set on age- and sex-specific incidence rates as well as on geographic (Western vs. Eastern Germany) and seasonal differences.
• Outcomes:
  The primary outcome of this study was the occurrence of GBS, defined by inpatient ICD-10-GM codes, In subanalyses different case definitions were applied (e.g. additional consideration of diagnostic procedures).
• Data analysis plan:
  A retrospective cohort design was applied to estimate the incidence of GBS in the study population for the years 2007-2009. A case of GBS was considered as incident if a GBS diagnosis-free period of at least 12 months preceded a GBS diagnosis. For the main analysis cases were defined by the ICD-10-GM code G61.0 if this was coded as the main discharge diagnosis in inpatient data. In sub- and sensitivity analyses different case definitions were applied in order to assess the effect of the specificity of case definitions on potential variations in incidence estimates. Crude as well as standardized incidence rates per 100,000 person years were calculated for the entire study period and for each study year. Results were stratified by sex, age group, region and season.