Pregnancy as a risk factor for severe influenza infection: an individual participant data meta-analysis

FLURISK-INVESTIGATORS

Research output: Contribution to journalArticle

Abstract

Background WHO identifies pregnant women to be at increased risk for severe outcomes from influenza virus infections and recommends that they be prioritized for influenza vaccination. The evidence supporting this, however, is inconsistent. Ecologic studies in particular suggest more severe outcomes from influenza infection during pregnancy than studies based on individual patient data. Individual studies however may be underpowered and, as reported in a previous systematic review, confounding factors could not be adjusted for. We therefore conducted an individual participant data meta-analysis to assess the risk for severe outcomes of influenza infection in pregnant women while adjusting for other prognostic factors. Methods We contacted authors of studies included in a recently published systematic review. We pooled the individual participant data of women of reproductive age and laboratory confirmation of influenza virus infection. We used a generalized linear mixed model and reported odds ratios (OR) and 95% confidence intervals (CI). Results A total of 33 datasets with data on 186,656 individuals were available, including 36,498 eligible women of reproductive age and known pregnancy status. In the multivariable model, pregnancy was associated with a 7 times higher risk of hospital admission (OR 6.80, 95%CI 6.02-7.68), among patients receiving medical care as in- or outpatients, pregnancy was associated with a lower risk of admission to intensive care units (ICU; OR 0.57, 95%CI 0.48-0.69), and was not significantly associated with death (OR 1.00, 95%CI 0.75-1.34). Conclusions Our study found a higher risk of influenza associated hospitalization among pregnant women as compared to non-pregnant women. We did not find a higher mortality rate or higher likelihood of ICU admission among pregnant women who sought medical care. However, this study did not address whether a true community based cohort of pregnant women is at higher risk of influenza associated complications.

Original languageEnglish
Article number683
Number of pages10
JournalBMC Infectious Diseases
Volume19
Issue number1
DOIs
Publication statusPublished - 2 Aug 2019

Cite this

@article{12474b1acbaf4f21938f7c60bd1b7250,
title = "Pregnancy as a risk factor for severe influenza infection: an individual participant data meta-analysis",
abstract = "Background WHO identifies pregnant women to be at increased risk for severe outcomes from influenza virus infections and recommends that they be prioritized for influenza vaccination. The evidence supporting this, however, is inconsistent. Ecologic studies in particular suggest more severe outcomes from influenza infection during pregnancy than studies based on individual patient data. Individual studies however may be underpowered and, as reported in a previous systematic review, confounding factors could not be adjusted for. We therefore conducted an individual participant data meta-analysis to assess the risk for severe outcomes of influenza infection in pregnant women while adjusting for other prognostic factors. Methods We contacted authors of studies included in a recently published systematic review. We pooled the individual participant data of women of reproductive age and laboratory confirmation of influenza virus infection. We used a generalized linear mixed model and reported odds ratios (OR) and 95{\%} confidence intervals (CI). Results A total of 33 datasets with data on 186,656 individuals were available, including 36,498 eligible women of reproductive age and known pregnancy status. In the multivariable model, pregnancy was associated with a 7 times higher risk of hospital admission (OR 6.80, 95{\%}CI 6.02-7.68), among patients receiving medical care as in- or outpatients, pregnancy was associated with a lower risk of admission to intensive care units (ICU; OR 0.57, 95{\%}CI 0.48-0.69), and was not significantly associated with death (OR 1.00, 95{\%}CI 0.75-1.34). Conclusions Our study found a higher risk of influenza associated hospitalization among pregnant women as compared to non-pregnant women. We did not find a higher mortality rate or higher likelihood of ICU admission among pregnant women who sought medical care. However, this study did not address whether a true community based cohort of pregnant women is at higher risk of influenza associated complications.",
keywords = "Influenza, Vaccine, Pregnancy, Severity, Meta-analysis, A H1N1 VIRUS, HOSPITALIZED-PATIENTS, A(H1N1)PDM09 INFECTION, SEVERE OUTCOMES, UNITED-STATES, WOMEN, SURVEILLANCE, PNEUMONIA, FEATURES, SEASONS",
author = "FLURISK-INVESTIGATORS and Dominik Mertz and Lo, {Calvin Ka-Fung} and Lyubov Lytvyn and Ortiz, {Justin R.} and Mark Loeb and Ang, {Li Wei} and Anlikumar, {Mehta Asmita} and Isabelle Bonmarin and {Hugo Borja-Aburto}, Victor and Heinz Burgmann and Jordi Carratala and Gerardo Chowell and Catia Cilloniz and Jessica Cohen and Jeffery Cutter and Laurent Filleul and Shikha Garg and Steffen Geis and Melissa Helferty and Wan-Ting Huang and Seema Jain and Sevic, {Biljana Joves} and Paul Kelly and Gabriela Kusznierz and Nicola Lehners and Luana Lenzi and Ling, {Ivan T.} and Robyn Mitchell and Mulrennan, {Siobhain A.} and Nishioka, {Sergio A.} and Robert Norton and Oh, {Won Sup} and Pablo Orellano and Wolfgang Poeppl and Roberto Pontarolo and Odette Popovici and Alejandro Rodriquez and Bettina Schlehe and Paul Schnitzler and Bunyamin Sertogullarindan and Yuelong Shu and Geoffrey Taylor and Thompson, {Deborah L.} and Antoni Torres and {van Gageldonk-Lafeber}, {Arianne B.} and Diego Viasus and Quanyi Wang and Cuiling Xu",
year = "2019",
month = "8",
day = "2",
doi = "10.1186/s12879-019-4318-3",
language = "English",
volume = "19",
journal = "BMC Infectious Diseases",
issn = "1471-2334",
publisher = "BMC Proceedings",
number = "1",

}

Pregnancy as a risk factor for severe influenza infection : an individual participant data meta-analysis. / FLURISK-INVESTIGATORS.

In: BMC Infectious Diseases, Vol. 19, No. 1, 683, 02.08.2019.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Pregnancy as a risk factor for severe influenza infection

T2 - an individual participant data meta-analysis

AU - FLURISK-INVESTIGATORS

AU - Mertz, Dominik

AU - Lo, Calvin Ka-Fung

AU - Lytvyn, Lyubov

AU - Ortiz, Justin R.

AU - Loeb, Mark

AU - Ang, Li Wei

AU - Anlikumar, Mehta Asmita

AU - Bonmarin, Isabelle

AU - Hugo Borja-Aburto, Victor

AU - Burgmann, Heinz

AU - Carratala, Jordi

AU - Chowell, Gerardo

AU - Cilloniz, Catia

AU - Cohen, Jessica

AU - Cutter, Jeffery

AU - Filleul, Laurent

AU - Garg, Shikha

AU - Geis, Steffen

AU - Helferty, Melissa

AU - Huang, Wan-Ting

AU - Jain, Seema

AU - Sevic, Biljana Joves

AU - Kelly, Paul

AU - Kusznierz, Gabriela

AU - Lehners, Nicola

AU - Lenzi, Luana

AU - Ling, Ivan T.

AU - Mitchell, Robyn

AU - Mulrennan, Siobhain A.

AU - Nishioka, Sergio A.

AU - Norton, Robert

AU - Oh, Won Sup

AU - Orellano, Pablo

AU - Poeppl, Wolfgang

AU - Pontarolo, Roberto

AU - Popovici, Odette

AU - Rodriquez, Alejandro

AU - Schlehe, Bettina

AU - Schnitzler, Paul

AU - Sertogullarindan, Bunyamin

AU - Shu, Yuelong

AU - Taylor, Geoffrey

AU - Thompson, Deborah L.

AU - Torres, Antoni

AU - van Gageldonk-Lafeber, Arianne B.

AU - Viasus, Diego

AU - Wang, Quanyi

AU - Xu, Cuiling

PY - 2019/8/2

Y1 - 2019/8/2

N2 - Background WHO identifies pregnant women to be at increased risk for severe outcomes from influenza virus infections and recommends that they be prioritized for influenza vaccination. The evidence supporting this, however, is inconsistent. Ecologic studies in particular suggest more severe outcomes from influenza infection during pregnancy than studies based on individual patient data. Individual studies however may be underpowered and, as reported in a previous systematic review, confounding factors could not be adjusted for. We therefore conducted an individual participant data meta-analysis to assess the risk for severe outcomes of influenza infection in pregnant women while adjusting for other prognostic factors. Methods We contacted authors of studies included in a recently published systematic review. We pooled the individual participant data of women of reproductive age and laboratory confirmation of influenza virus infection. We used a generalized linear mixed model and reported odds ratios (OR) and 95% confidence intervals (CI). Results A total of 33 datasets with data on 186,656 individuals were available, including 36,498 eligible women of reproductive age and known pregnancy status. In the multivariable model, pregnancy was associated with a 7 times higher risk of hospital admission (OR 6.80, 95%CI 6.02-7.68), among patients receiving medical care as in- or outpatients, pregnancy was associated with a lower risk of admission to intensive care units (ICU; OR 0.57, 95%CI 0.48-0.69), and was not significantly associated with death (OR 1.00, 95%CI 0.75-1.34). Conclusions Our study found a higher risk of influenza associated hospitalization among pregnant women as compared to non-pregnant women. We did not find a higher mortality rate or higher likelihood of ICU admission among pregnant women who sought medical care. However, this study did not address whether a true community based cohort of pregnant women is at higher risk of influenza associated complications.

AB - Background WHO identifies pregnant women to be at increased risk for severe outcomes from influenza virus infections and recommends that they be prioritized for influenza vaccination. The evidence supporting this, however, is inconsistent. Ecologic studies in particular suggest more severe outcomes from influenza infection during pregnancy than studies based on individual patient data. Individual studies however may be underpowered and, as reported in a previous systematic review, confounding factors could not be adjusted for. We therefore conducted an individual participant data meta-analysis to assess the risk for severe outcomes of influenza infection in pregnant women while adjusting for other prognostic factors. Methods We contacted authors of studies included in a recently published systematic review. We pooled the individual participant data of women of reproductive age and laboratory confirmation of influenza virus infection. We used a generalized linear mixed model and reported odds ratios (OR) and 95% confidence intervals (CI). Results A total of 33 datasets with data on 186,656 individuals were available, including 36,498 eligible women of reproductive age and known pregnancy status. In the multivariable model, pregnancy was associated with a 7 times higher risk of hospital admission (OR 6.80, 95%CI 6.02-7.68), among patients receiving medical care as in- or outpatients, pregnancy was associated with a lower risk of admission to intensive care units (ICU; OR 0.57, 95%CI 0.48-0.69), and was not significantly associated with death (OR 1.00, 95%CI 0.75-1.34). Conclusions Our study found a higher risk of influenza associated hospitalization among pregnant women as compared to non-pregnant women. We did not find a higher mortality rate or higher likelihood of ICU admission among pregnant women who sought medical care. However, this study did not address whether a true community based cohort of pregnant women is at higher risk of influenza associated complications.

KW - Influenza

KW - Vaccine

KW - Pregnancy

KW - Severity

KW - Meta-analysis

KW - A H1N1 VIRUS

KW - HOSPITALIZED-PATIENTS

KW - A(H1N1)PDM09 INFECTION

KW - SEVERE OUTCOMES

KW - UNITED-STATES

KW - WOMEN

KW - SURVEILLANCE

KW - PNEUMONIA

KW - FEATURES

KW - SEASONS

U2 - 10.1186/s12879-019-4318-3

DO - 10.1186/s12879-019-4318-3

M3 - Article

VL - 19

JO - BMC Infectious Diseases

JF - BMC Infectious Diseases

SN - 1471-2334

IS - 1

M1 - 683

ER -