Risk of Guillain-Barré syndrome after meningococcal conjugate vaccination.
OBJECTIVE
A new meningococcal conjugate vaccine (MCV4) was introduced in 2005. Shortly after, case reports of Guillain-Barré syndrome (GBS), a serious demyelinating disease, began to be reported to the Vaccine Adverse Event Reporting System. In 2006, the Centers for Disease Control and Prevention and the Food and Drug Administration requested the evaluation of GBS risk after MCV4 vaccination. We conducted a study to assess the risk of GBS after MCV4 vaccination using health plan administrative and claims data together with the review of primary medical records of potential cases.


METHODS
Retrospective cohort study among 12.6 million 11- to 21-year-old members of five US health plans with a total membership of 50 million. Automated enrollment and medical claims data from March 2005 through August 2008 were used to identify the population, the vaccinations administered, and the medical services associated with possible GBS. Medical records were reviewed and adjudicated by a neurologist panel to confirm cases of GBS. The study used distributed data analysis methods that minimized sharing of protected health information.


RESULTS
We confirmed 99 GBS cases during 18,322,800 person-years (5.4/1,000,000 person-years). More than 1.4 million MCV4 vaccinations were observed. No confirmed cases of GBS occurred within 6 weeks after vaccination. The upper 95% CI for the attributable risk of GBS associated with MCV4 is estimated as 1.5 cases per 1,000,000 doses.


CONCLUSIONS
Among members of five US health plans, MCV4 vaccination was not associated with increased GBS risk.
Department of Population Medicine, Harvard Medical School and Harvard Pilgrim Health Care Institute, Boston, MA, USA. pvelentgas@outcome.com
Priscilla
P
Velentgas
Anthony A
AA
Amato
Rhonda L
RL
Bohn
K Arnold
KA
Chan
Thomas
T
Cochrane
Donnie P
DP
Funch
Inna
I
Dashevsky
April L
AL
Duddy
Patricia
P
Gladowski
Steven A
SA
Greenberg
Judith M
JM
Kramer
Cheryl
C
McMahill-Walraven
Cynthia
C
Nakasato
Claire M
CM
Spettell
Beth L
BL
Syat
Peter M
PM
Wahl
Alexander M
AM
Walker
Fang
F
Zhang
Jeffrey S
JS
Brown
Richard
R
Platt
D000293:Adolescent; D000328:Adult; D002648:Child; D015331:Cohort Studies; D005260:Female; D020275:Guillain-Barre Syndrome / Q000209:etiology*; D006801:Humans; D008297:Male; D022401:Meningococcal Vaccines / Q000009:adverse effects; D012189:Retrospective Studies; D012306:Risk; D014611:Vaccination / Q000009:adverse effects*; D018074:Vaccines, Conjugate / Q000009:adverse effects
D022401:Meningococcal Vaccines; D018074:Vaccines, Conjugate