Association of higher adiposity and wheezing in infants with lower respiratory illnesses

Infant antibiotic exposure and the development of childhood overweight and central adiposity

BACKGROUND

Obesity has been associated with disruption of the gut microbiota, which is established during infancy and vulnerable to disruption by antibiotics.

OBJECTIVES

To investigate the association between early-life antibiotic exposure and subsequent development of overweight and central adiposity.

METHODS

Provincial health-care records were linked to clinical and survey data from a Canadian longitudinal birth cohort study. Antibiotic exposure during the first year of life was documented from prescription records. Overweight and central adiposity were determined from anthropometric measurements at ages 9 (n=616) and 12 (n=431). Associations were determined by multiple logistic regression.

RESULTS

Infants receiving antibiotics in the first year of life were more likely to be overweight later in childhood compared with those who were unexposed (32.4 versus 18.2% at age 12, P=0.002). Following adjustment for birth weight, breastfeeding, maternal overweight and other potential confounders, this association persisted in boys (aOR 5.35, 95% confidence interval (CI) 1.94-14.72) but not in girls (aOR 1.13, CI 0.46-2.81). Similar gender-specific associations were found for overweight at age 9 (aOR 2.19, CI 1.06-4.54 for boys; aOR 1.20, CI 0.53-2.70 for girls) and for high central adiposity at age 12 (aOR 2.85, CI 1.24-6.51 for boys; aOR 1.59, CI 0.68-3.68 for girls).

CONCLUSIONS

Among boys, antibiotic exposure during the first year of life was associated with an increased risk of overweight and central adiposity in preadolescence, indicating that antibiotic stewardship is particularly important during infancy. Given the current epidemic of childhood obesity and the high prevalence of infant antibiotic exposure, further studies are necessary to determine the mechanisms underlying this association, to identify the long-term health consequences, and to develop strategies for mitigating these effects when antibiotic exposure cannot be avoided.

Weight gain in infancy and post-bronchiolitis wheezing

AIM

Low birth weight, high birth weight and excessive weight gain after birth may be risk factors for asthma in childhood, but their associations with wheezing in early childhood are poorly studied. The aim of the study was to evaluate birth weight, weight gain in early infancy and overweight in infancy assessed by weight for length (WFL) as risk factors for wheezing after hospitalization for bronchiolitis in early infancy.

METHODS

In all, 127 full-term infants hospitalized for bronchiolitis at age <6 months have been followed up until the mean age of 1.5 years. The weights and lengths of the infants were measured on admission to hospital and at the control visit. Birth weights were obtained from the hospital records.

RESULTS

Both occurrence and recurrence of post-bronchiolitis wheezing were associated with birth weight >4000 g and the recurrence of post-bronchiolitis wheezing with WFL >110% at age 1.5 years. The associations were robust to adjustments with gender and allergy. Higher weight gain from birth to hospitalization at age <6 months was associated with wheezing in the subgroup of children with birth weight >4000 g.

CONCLUSION

High birth weight and the development of overweight may be associated with post-bronchiolitis wheezing in infancy.