Near real-time surveillance for Guillain-Barré syndrome after influenza vaccination among the Medicare population, 2010/11 to 2013/14

Sukhminder K Sandhu; Wei Hua; Thomas E MaCurdy; Riley L Franks; Armen Avagyan; Jeffrey Kelman; Christopher M Worrall; Robert Ball; Michael Nguyen

doi:10.1016/j.vaccine.2017.03.087

Near real-time surveillance for Guillain-Barré syndrome after influenza vaccination among the Medicare population, 2010/11 to 2013/14

Vaccine. 2017 May 19;35(22):2986-2992. doi: 10.1016/j.vaccine.2017.03.087. Epub 2017 Apr 24.

Authors

Sukhminder K Sandhu¹, Wei Hua², Thomas E MaCurdy³, Riley L Franks⁴, Armen Avagyan⁴, Jeffrey Kelman⁵, Christopher M Worrall⁵, Robert Ball², Michael Nguyen²

Affiliations

¹ Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, MD, USA. Electronic address: sukhminder.sandhu@fda.hhs.gov.
² Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, MD, USA.
³ Stanford University, Stanford, CA, USA; Acumen LLC, Burlingame, CA, USA.
⁴ Acumen LLC, Burlingame, CA, USA.
⁵ Centers for Medicare and Medicaid Services, Washington, DC, USA.

PMID: 28449973
DOI: 10.1016/j.vaccine.2017.03.087

Abstract

Background: Guillain-Barré syndrome (GBS) is a serious acute demyelinating disease that causes weakness and paralysis. The Food and Drug Administration (FDA) began collaborating with the Centers for Medicare and Medicaid Services (CMS) to develop near real-time vaccine safety surveillance capabilities in 2006 and has been monitoring for the risk of GBS after influenza vaccination for every influenza season since 2008.

Methods: We present results from the 2010/11 to 2013/14 influenza seasons using the Updating Sequential Probability Ratio Test (USPRT), with an overall 1-sided α of 0.05 apportioned equally using a constant alpha-spending plan among 20 consecutive weekly tests, 5 ad hoc tests, and a 26th final end of season test. Observed signals were investigated using the self-controlled risk interval (SCRI) design.

Results: Over 15 million people were vaccinated in each influenza season. In the 2010/11 influenza season, we observed an elevated GBS risk during the season, with an end of season SCRI analysis finding a nonsignificant increased risk (RR=1.25, 95% CI: 0.96-1.63). A sensitivity analysis applying the positive predictive value of the ICD-9 code for GBS from the 2009/10 season estimated a RR=1.98 (95% CI: 1.42-2.76). Although the 2010/11 influenza vaccine suggested an increased GBS risk, surveillance of the identical vaccine in the 2011/12 influenza season did not find an increased GBS risk after vaccination. No signal was observed in the subsequent three influenza seasons.

Conclusions: Conducting near real-time surveillance using USPRT has proven to be an excellent method for near real-time GBS surveillance after influenza vaccination, as demonstrated by our surveillance efforts during the 2010/11-2013/14 influenza seasons. In the 2010/2011 influenza season, in addition to the 2009 H1N1 influenza pandemic, using near real-time surveillance we were able to observe a signal early in the influenza season and the method has now become routine.

Keywords: Flu; Guillain-Barré syndrome; Immunization; Influenza; Vaccine.

Published by Elsevier Ltd.

MeSH terms

Aged
Aged, 80 and over
Centers for Medicare and Medicaid Services, U.S.
Computer Systems
Female
Guillain-Barre Syndrome / epidemiology*
Guillain-Barre Syndrome / etiology
Humans
Influenza Vaccines / administration & dosage
Influenza Vaccines / adverse effects*
Male
Medicare*
Population Surveillance / methods*
Risk Assessment
United States / epidemiology
United States Food and Drug Administration
Vaccination

Substances

Influenza Vaccines