Toxic metals and trace elements in maternal blood and urinary tract infection during the first 2 years of life: The Japan Environment and Children's Study.

BACKGROUND

Urinary tract infections (UTIs) are common bacterial infections in young children and can lead to long-term renal complications. While established risk factors exist, the effect of prenatal exposure to toxic metals and trace elements on UTI risk remains unclear. We examined the association between maternal blood levels of these elements and UTI risk in early childhood.

METHODS

This study is based on a nationwide birth cohort, the Japan Environment and Children's Study (JECS), which obtained data from over 100,000 pregnancies through 15 Regional Centres across Japan. Maternal blood samples were collected during mid-late pregnancy and the concentrations of selenium, manganese, lead, cadmium, and mercury were measured. Child UTI diagnoses during the first 2 years of life were assessed by caregiver questionnaires. Multivariable logistic regression models examined associations between log2-transformed level of metals and trace elements and UTI.

RESULTS

Overall, 79,161 mother-child pairs were analyzed. During the first 2 years, 877 (1.1 %) children were diagnosed with UTI. Higher maternal selenium levels were associated with increased UTI risk (Odds ratio for a twofold increase in selenium: 1.58, 95 % CI: 1.06-2.35) after adjusting for covariates. The adjusted odds ratios (95 % CI) of other elements were 0.97 (0.82-1.14) in manganese, 1.01 (0.88-1.15) in lead, 0.94 (0.84-1.05) in cadmium, and 1.02 (0.93-1.11) in mercury.

CONCLUSIONS

Elevated maternal selenium levels may increase susceptibility to UTIs during the first 2 years of life. Further studies are needed to investigate long-term effects, including bladder and kidney dysfunction.