TY - JOUR
T1 - Retesting the hypothesis that early Diphtheria-Tetanus-Pertussis vaccination increases female mortality
T2 - An observational study within a randomised trial
AU - Sørensen, Marcus Kjær
AU - Schaltz-Buchholzer, Frederik
AU - Jensen, Andreas Møller
AU - Nielsen, Sebastian
AU - Monteiro, Ivan
AU - Aaby, Peter
AU - Benn, Christine Stabell
N1 - Funding Information:
The first BCG trial was funded by the European Union (ICA4-CT-2002-10053), the March of Dimes, and the Danish National Research Foundation and the present trial was supported by The European Research Council (starting grant ERC-2009-StG-243149, which also funded IM and CSB); the Novo Nordisk Foundation (research professorship grant to PA); the Danish National Research Foundation (grant DNRF108 to the Research Centre for Vitamins & Vaccines); DANIDA, European Union FP7, and OPTIMUNISE (grant Health-F3-2011–261375 to the Bandim Health Project). The Novo Nordisk Foundation and Det Medicinske Selskab i København funded a pre-graduate scholarship for MKS. The Augustinus Foundation and The Novo Nordisk Foundation funded office and travel expenses for MKS. FSB, AMJ and SN were funded by a 1-year PhD scholarship from the University of Southern Denmark.
PY - 2022/3/8
Y1 - 2022/3/8
N2 - Background: There are worrying indications that diphtheria-tetanus-pertussis (DTP) vaccine has negative non-specific effects for females. We previously found, in a trial of early-Bacillus Calmette-Guérin (BCG) to low weight (LW) neonates, that receiving early-DTP (before 2 months of age), was associated with increased female mortality compared with no-DTP/delayed-DTP. Within a subsequent LW trial, we aimed to retest this observation. Methods: Between 2010 and 2014, in Guinea-Bissau, 2,398 infants were randomised 1:1 to early-BCG (intervention) or delayed-BCG (standard practice for LW neonates) and visited at 2, 6 and 12 months of age to assess nutritional and vaccination status. DTP is recommended at 6 weeks of age. We examined the effect of having “early-DTP” versus “no-DTP” at the time of the 2-month visit on all-cause mortality between the 2- and 6-month visits in Cox models stratified by sex and adjusted for BCG-group and 2-month-weight-for-age (z-scores) providing adjusted mortality rate ratios (aMRRs). We analysed to which extent conditions varied between the present and the previous LW trials and how that might have affected the overall result of comparing the early-DTP and the no-DTP groups. Results: At the time of the 2-month visit, 75% (1,795/2,398) had received DTP. Those vaccinated had better anthropometric indices than no-DTP infants at birth and by 2 months of age. Between the 2- and 6-month visits, 29 deaths occurred. The early-DTP/no-DTP aMRR was 1.09 (95% CI: 0.44–2.69); 1.19 (0.45–3.15) for females and 0.77 (0.14–4.19) for males. Compared to the previous study, the present study cohort had 56% (30–72%) lower overall mortality, fewer no-DTP infants, higher BCG vaccination coverage and several more oral polio vaccine campaigns. Conclusion: We did not find that early-DTP was associated with increased female mortality as found in a previous study; differences in results may partly be due to a decline in overall mortality and changes in vaccination practices.
AB - Background: There are worrying indications that diphtheria-tetanus-pertussis (DTP) vaccine has negative non-specific effects for females. We previously found, in a trial of early-Bacillus Calmette-Guérin (BCG) to low weight (LW) neonates, that receiving early-DTP (before 2 months of age), was associated with increased female mortality compared with no-DTP/delayed-DTP. Within a subsequent LW trial, we aimed to retest this observation. Methods: Between 2010 and 2014, in Guinea-Bissau, 2,398 infants were randomised 1:1 to early-BCG (intervention) or delayed-BCG (standard practice for LW neonates) and visited at 2, 6 and 12 months of age to assess nutritional and vaccination status. DTP is recommended at 6 weeks of age. We examined the effect of having “early-DTP” versus “no-DTP” at the time of the 2-month visit on all-cause mortality between the 2- and 6-month visits in Cox models stratified by sex and adjusted for BCG-group and 2-month-weight-for-age (z-scores) providing adjusted mortality rate ratios (aMRRs). We analysed to which extent conditions varied between the present and the previous LW trials and how that might have affected the overall result of comparing the early-DTP and the no-DTP groups. Results: At the time of the 2-month visit, 75% (1,795/2,398) had received DTP. Those vaccinated had better anthropometric indices than no-DTP infants at birth and by 2 months of age. Between the 2- and 6-month visits, 29 deaths occurred. The early-DTP/no-DTP aMRR was 1.09 (95% CI: 0.44–2.69); 1.19 (0.45–3.15) for females and 0.77 (0.14–4.19) for males. Compared to the previous study, the present study cohort had 56% (30–72%) lower overall mortality, fewer no-DTP infants, higher BCG vaccination coverage and several more oral polio vaccine campaigns. Conclusion: We did not find that early-DTP was associated with increased female mortality as found in a previous study; differences in results may partly be due to a decline in overall mortality and changes in vaccination practices.
KW - Bacille Calmette-Guérin vaccine
KW - Diphtheria-Tetanus-Pertussis vaccine
KW - DTP
KW - Heterologous effects
KW - Infant mortality
KW - Non-specific effects of vaccines
KW - Sex-differential effects of vaccines
U2 - 10.1016/j.vaccine.2021.06.008
DO - 10.1016/j.vaccine.2021.06.008
M3 - Journal article
C2 - 34217570
AN - SCOPUS:85109011586
SN - 0264-410X
VL - 40
SP - 1606
EP - 1616
JO - Vaccine
JF - Vaccine
IS - 11
ER -