tetano
Editor, Senior Moderator
Vaccine. 2017 Apr 24. pii: S0264-410X(17)30439-5. doi: 10.1016/j.vaccine.2017.03.087. [Epub ahead of print]
[h=1]Near real-time surveillance for Guillain-Barr? syndrome after influenza vaccination among the Medicare population, 2010/11 to 2013/14.[/h] Sandhu SK[SUP]1[/SUP], Hua W[SUP]2[/SUP], MaCurdy TE[SUP]3[/SUP], Franks RL[SUP]4[/SUP], Avagyan A[SUP]4[/SUP], Kelman J[SUP]5[/SUP], Worrall CM[SUP]5[/SUP], Ball R[SUP]2[/SUP], Nguyen M[SUP]2[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] [h=4]BACKGROUND:[/h] Guillain-Barr? 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.
[h=4]METHODS:[/h] 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.
[h=4]RESULTS:[/h] 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.
[h=4]CONCLUSIONS:[/h] 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.
Published by Elsevier Ltd.
[h=4]KEYWORDS:[/h] Flu; Guillain-Barr? syndrome; Immunization; Influenza; Vaccine
PMID: 28449973 DOI: 10.1016/j.vaccine.2017.03.087
[h=1]Near real-time surveillance for Guillain-Barr? syndrome after influenza vaccination among the Medicare population, 2010/11 to 2013/14.[/h] Sandhu SK[SUP]1[/SUP], Hua W[SUP]2[/SUP], MaCurdy TE[SUP]3[/SUP], Franks RL[SUP]4[/SUP], Avagyan A[SUP]4[/SUP], Kelman J[SUP]5[/SUP], Worrall CM[SUP]5[/SUP], Ball R[SUP]2[/SUP], Nguyen M[SUP]2[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] [h=4]BACKGROUND:[/h] Guillain-Barr? 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.
[h=4]METHODS:[/h] 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.
[h=4]RESULTS:[/h] 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.
[h=4]CONCLUSIONS:[/h] 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.
Published by Elsevier Ltd.
[h=4]KEYWORDS:[/h] Flu; Guillain-Barr? syndrome; Immunization; Influenza; Vaccine
PMID: 28449973 DOI: 10.1016/j.vaccine.2017.03.087