title: Early diphtheria-tetanus-pertussis vaccination associated with higher female mortality and no difference in male mortality in a cohort of low birthweight children: an observational study within a randomised trial.
abstract: BACKGROUND
  Studies from low-income countries have suggested that diphtheria-tetanus-pertussis (DTP) vaccine provided after Bacille Calmette-Guerin (BCG) vaccination may have a negative effect on female survival. The authors examined the effect of DTP in a cohort of low birthweight (LBW) infants.
  
  
  METHODS
  2320 LBW newborns were visited at 2, 6 and 12 months of age to assess nutritional and vaccination status. The authors examined survival until the 6-month visit for children who were DTP vaccinated and DTP unvaccinated at the 2-month visit.
  
  
  RESULTS
  Two-thirds of the children had received DTP at 2 months and 50 deaths occurred between the 2-month and 6-month visits. DTP vaccinated children had a better anthropometric status for all indices than DTP unvaccinated children. Small mid-upper arm circumference (MUAC) was the strongest predictor of mortality. The death rate ratio (DRR) for DTP vaccinated versus DTP unvaccinated children differed significantly for girls (DRR 2.45; 95% CI 0.93 to 6.45) and boys (DRR 0.53; 95% CI 0.23 to 1.20) (p=0.018, homogeneity test). Adjusting for MUAC, the overall effect for DTP vaccinated children was 2.62 (95% CI 1.34 to 5.09); DRR was 5.68 (95% CI 1.83 to 17.7) for girls and 1.29 (95% CI 0.56 to 2.97) for boys (p=0.023, homogeneity test). While anthropometric indices were a strong predictor of mortality among boys, there was little or no association for girls.
  
  
  CONCLUSIONS
  Surprisingly, even though the children with the best nutritional status were vaccinated early, early DTP vaccination was associated with increased mortality for girls.
authors.affiliation: Bandim Health Project, Statens Serum Institut, Artillerivej 5, 2300 Copenhagen S, Denmark. p.aaby@bandim.org
authors.forename: Peter
authors.initials: P
authors.lastname: Aaby
authors.forename: Henrik
authors.initials: H
authors.lastname: Ravn
authors.forename: Adam
authors.initials: A
authors.lastname: Roth
authors.forename: Amabelia
authors.initials: A
authors.lastname: Rodrigues
authors.forename: Ida Maria
authors.initials: IM
authors.lastname: Lisse
authors.forename: Birgitte Rode
authors.initials: BR
authors.lastname: Diness
authors.forename: Karen Rokkedal
authors.initials: KR
authors.lastname: Lausch
authors.forename: Najaaraq
authors.initials: N
authors.lastname: Lund
authors.forename: Julie
authors.initials: J
authors.lastname: Rasmussen
authors.forename: Sofie
authors.initials: S
authors.lastname: Biering-Sørensen
authors.forename: Hilton
authors.initials: H
authors.lastname: Whittle
authors.forename: Christine Stabell
authors.initials: CS
authors.lastname: Benn
mesh_terms: D000886:Anthropometry; D001500:BCG Vaccine / Q000008:administration & dosage; D015721:Diphtheria-Tetanus-Pertussis Vaccine / Q000008:administration & dosage / Q000009:adverse effects*; D005260:Female; D006169:Guinea-Bissau / Q000453:epidemiology; D006801:Humans; D007115:Immunization Schedule; D007223:Infant; D007226:Infant Mortality / Q000639:trends*; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D008297:Male; D009752:Nutritional Status; D016032:Randomized Controlled Trials as Topic; D012307:Risk Factors; D012737:Sex Factors; D016019:Survival Analysis
chemical_list: D001500:BCG Vaccine; D015721:Diphtheria-Tetanus-Pertussis Vaccine