Body mass index and vaccine responses following influenza vaccination during pregnancy

Michelle Clarke; Louise M Goodchild; Sue Evans; Lynne C Giles; Sheena G Sullivan; Ian G Barr; Stephen Lambert; Helen Marshall

doi:10.1016/j.vaccine.2021.06.065

Body mass index and vaccine responses following influenza vaccination during pregnancy

Vaccine. 2021 Aug 9;39(34):4864-4870. doi: 10.1016/j.vaccine.2021.06.065. Epub 2021 Jul 12.

Authors

Michelle Clarke¹, Louise M Goodchild², Sue Evans³, Lynne C Giles⁴, Sheena G Sullivan⁵, Ian G Barr⁶, Stephen Lambert⁷, Helen Marshall⁸

Affiliations

¹ Women's and Children's Health Network, North Adelaide, SA, Australia; Adelaide Medical School and The Robinson Research Institute, The University of Adelaide, Adelaide, SA, Australia. Electronic address: michelle.clarke@adelaide.edu.au.
² Women's and Children's Health Network, North Adelaide, SA, Australia. Electronic address: louise.goodchild@adelaide.edu.au.
³ Women's and Children's Health Network, North Adelaide, SA, Australia. Electronic address: sue.evans@adelaide.edu.au.
⁴ School of Public Health and The Robinson Research Institute, The University of Adelaide, Adelaide, SA, Australia. Electronic address: lynne.giles@adelaide.edu.au.
⁵ WHO Collaborating Centre for Reference and Research on Influenza, Royal Melbourne Hospital, at the Peter Doherty Institute for Infection and Immunity, Melbourne, VIC, Australia; Department of Infectious Diseases, University of Melbourne, at the Peter Doherty Institute for Infection and Immunity, Melbourne, VIC, Australia; Department of Epidemiology, University of California, Los Angeles, USA. Electronic address: sheena.sullivan@influenzacentre.org.
⁶ WHO Collaborating Centre for Reference and Research on Influenza, Royal Melbourne Hospital, at the Peter Doherty Institute for Infection and Immunity, Melbourne, VIC, Australia; Department of Microbiology and Immunology, University of Melbourne, at the Peter Doherty Institute for Infection and Immunity, Melbourne, VIC, Australia. Electronic address: ian.barr@influenzacentre.org.
⁷ Child Health Research Centre, The University of Queensland, South Brisbane, QLD, Australia. Electronic address: sblambert@uq.edu.au.
⁸ Women's and Children's Health Network, North Adelaide, SA, Australia; Adelaide Medical School and The Robinson Research Institute, The University of Adelaide, Adelaide, SA, Australia. Electronic address: helen.marshall@adelaide.edu.au.

PMID: 34266699
DOI: 10.1016/j.vaccine.2021.06.065

Abstract

Background and aims: Influenza vaccination is recommended by the World Health Organisation for pregnant women, offering the dual benefit of protecting pregnant women and their newborn infants against influenza infection. Various factors can influence vaccine immunogenicity, with obesity being one factor implicated in varied responses. This study aimed to investigate the impact of body mass index (BMI) on vaccine responses following influenza vaccination during pregnancy.

Methods: Pregnant women attending the Women's and Children's Hospital in South Australia during 2014-2016 were invited to participate. Participant's clinical and demographic factors were recorded prior to administration of licensed seasonal influenza vaccination. Blood samples were collected before and one month post-vaccination to measure antibody responses by haemagglutination inhibition (HI) assay. Seroprotection was defined as a post-vaccination HI titre ≥ 1:40. Regression models assessed associations with failure to achieve seroprotective antibodies to H1, H3, and B influenza strains.

Results: A total of 96 women were enrolled in the study at a median gestation of 22 weeks with a BMI range of 18-49 kg/m². Paired sera samples were available for 90/96 (94%). Most pregnant women (72/90, 80%) demonstrated seroprotective antibody titres to all three influenza vaccine antigens (A(H1N1)pdm09, A(H3N2), B/Yamagata) following vaccination. Compared with women with BMI < 30 kg/m², those with high BMI were less likely to fail to achieve seroprotective antibodies, however this was not statistically significant (RR 0.42, 95% CI 0.11-1.68; p = 0.22). A greater proportion of women vaccinated during their second (47/53, 93%) or third trimester (18/25, 72%) demonstrated seroprotection to all three vaccine antigens following vaccination compared with women vaccinated during their first trimester (7/12, 58%).

Conclusion: High BMI did not impair seroprotection levels following influenza vaccination in pregnant women. Gestation at vaccination may be an important consideration for optimising vaccine protection for pregnant women and their newborns. Further assessment of first trimester influenza vaccine responses is warranted.

Keywords: Immunogenicity; Influenza; Obesity; Vaccination; Vaccine.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Antibodies, Viral
Body Mass Index
Child
Female
Humans
Infant
Infant, Newborn
Influenza A Virus, H1N1 Subtype*
Influenza A Virus, H3N2 Subtype
Influenza Vaccines*
Influenza, Human* / prevention & control
Pregnancy
Vaccination

Substances

Antibodies, Viral
Influenza Vaccines