Bacillus Calmette-Guérin vaccination at birth: Effects on infant growth. A randomized clinical trial

Abstract

Background: Bacillus Calmette-Guérin vaccine (BCG) induces a complex, pro-inflammatory immune response. Obesity is associated with low-grade inflammation.

Aims: The purpose of the study was to test whether BCG at birth has effects on infant growth and body composition.

Study design, subjects, and outcome measures: The Danish Calmette Study is a randomized, clinical trial. The study was conducted at three university hospitals and randomized 4262 children of gestational age ≥32weeks to receive BCG within seven days of birth or to a no-intervention control group. Follow-up consisted of clinical examinations. Outcome measures were weight and length at 3months, and weight, length, mid upper-arm circumference, and triceps and subscapular skinfold at 13months. Data collectors were blinded to allocation. Anthropometric measurements were converted to z-scores using WHO reference population.

Results: Follow-up was 94% complete at 3 and 13months after birth. The children were bigger than the WHO reference population. There was no effect of BCG on weight z-score at 13months (-0.028 [95% confidence interval: -0.085 to 0.029], p=0.34). There was no effect on weight and length at 3months, or length, mid-upper-arm circumference, or triceps and subscapular skinfold at 13months.

Conclusion: In this study, vaccination with BCG at birth did not have effects on child growth or body composition at 13months.

Trial registration: www.clinicaltrials.gov, registration number NCT01694108.

Keywords: BCG; Body composition; Child growth; Inflammation; Non-specific effect; Obesity.