Breastfeeding and the Risk of Urinary Tract Infection
in Children
by Anne Eglash MD, IBCLC, FABM
Urinary tract infections (UTIs) are relatively common in children, with approximately 2% of children (boys and girls) experiencing a UTI within the first 2 years of life. The authors of the research for today’s question conducted a systematic review and meta-analysis to determine risk factors for UTIs in children.
They reviewed 24 articles that met their rigorous quality inclusion criteria. They found that circumcision was strongly protective of UTIs in boys, with an odds ratio of 0.1, or a 90% decreased risk of UTIs compared to boys who are not circumcised.
Factors that were found to be associated with higher risk of UTIs included poor fluid intake, infrequent voiding, family history, vesicoureteral reflux, infrequent stooling, and obesity.
What about breastfeeding? See the question!
- Breastfeeding is associated with a 60% lower likelihood of UTIs in children.
- Once weaned, a breastfed child no longer has a lower risk of UTI.
- Breastfeeding is more strongly associated with fewer UTIs in children right after birth than later.
- Breastfeeding may decrease the risk of UTIs by decreasing the risk of childhood obesity.
See the Answer
Abstract
Context
The incidence of urinary tract infection (UTI) varies with age, but there is limited evidence on the role of other risk factors.
Objective
The aim of this meta-analysis was to investigate the risk factors for UTIs in children.
Data sources
PubMed from 1966 to May 2019.
Study selection
All studies assessing at least 1 possible risk factor for occurrence or recurrence of UTI with a clear definition of symptomatic UTI in children were eligible. We excluded studies with UTIs related to hospital treatment or severe congenital renal abnormalities.
Data extraction
After the quality assessment we extracted data on the given risk factor in children with and without UTI. The data were extracted separately for the occurrence and recurrence of UTIs.
Results
We included 24 studies in the meta-analysis. Circumcision decreased the occurrence of UTIs with an odds ratio (OR) of 0.1 [95% confidence interval (CI): 0.06–0.17) and breast-feeding with an OR of 0.4 (CI: 0.19–0.86), both with low heterogeneity. Being overweight or obese increased the risk of UTI (OR: 2.23; CI: 1.37–3.63). Both poor fluid intake (OR: 6.39; CI: 3.07–13.39) and infrequent voiding (OR: 3.54; CI: 1.68– 7.46) were associated with recurrent UTIs.
Limitations
The design, populations and definitions varied between the studies.
Conclusions
Being overweight or obese and having poor fluid intake are modifiable risk factors that increase the risk for UTIs in children. Breastfeeding and circumcision are associated with a decreased occurrence of UTIs.
This systematic review and meta-analysis found 3 good quality studies that investigated the relationship between breastfeeding and UTI. They found that breastfeeding is associated with a 60% lower likelihood of UTIs in children. Most of the effect was soon after birth, but in one study, the protective effect of breastfeeding lasted beyond weaning.
The researchers found that childhood obesity was associated with a 2.25 times increased risk of UTIs, not just in infants, but in older children. Therefore, breastfeeding may have a longer lasting impact on the risk of childhood UTIs, beyond infancy, by reducing the risk of obesity.
That is not to say that the protection from UTIs by breastfeeding is 100% mediated by lowering the risk of childhood obesity. A 1990 study and a 2014 study investigated the presence and function of oligosaccharides in the urine of breastfed infants. They found that oligosaccharides from breastmilk were not only present in the infant urine but were also shown to decrease the invasion of E Coli bacteria into the lining of the bladder.
J. Rolando Figueroa, MD-FACOG
Thanks Anne, as long as I can recall this relationship, of exclusive breastfeeding with lower UTI was even proven when newborns were fed even sterile water. Thanks for updating and expanding this protective factor, particularly with obesity, frequent voiding and liquids intake.