Does early life exposure to antibiotics increase the risk of eczema? A systematic review.

A number of studies have suggested that early life exposure to antibiotics can lead to an increased risk of developing eczema. This systematic review and meta-analysis of observational studies, involving children or young adults aged 0-25 years, assessed the impact of antibiotic exposure either in utero or during the first 12 months of life on subsequent eczema risk. Twenty studies examined the association between prenatal and/or postnatal exposure to antibiotics and development of eczema. The pooled odds ratio (OR) for the 17 studies examining postnatal antibiotic exposure was 1.41 [95% confidence interval (CI) 1.30-1.53]. The pooled OR for the 10 longitudinal studies was 1.40 (95% CI 1.19-1.64), compared with a pooled OR of 1.43 (95% CI 1.36-1.51) for the seven cross-sectional studies. There was a significant dose-response association, suggesting a 7% increase in the risk of eczema for each additional antibiotic course received during the first year of life [pooled OR 1.07 (95% CI 1.02-1.11)]. Finally, the pooled OR for the four studies relating to antenatal exposure was 1.30 (95% CI 0.86-1.95). We conclude that exposure to antibiotics in the first year of life, but not prenatally, is more common in children with eczema.