Effects of mixed heavy metals on kidney function in premenopausal and postmenopausal women

To evaluate the relationships between heavy metals (cadmium, lead, and mercury) and their mixtures and estimated glomerular filtration rate (eGFR) in premenopausal and postmenopausal women.

Using data from the Korean National Health and Nutrition Examination Survey (2009-2017), multivariate linear regression models, marginal effects, and weighted quantile sum regression, we assessed the associations between single heavy metals and their mixtures and eGFR among 5,372 women.

Risks of reduced eGFR, comorbidities, and heavy metal exposure were found to be higher in postmenopausal women than in premenopausal women. A negative association of cadmium ( β = -2.97; 95% CI, -5.10 to -0.85) and a positive association of mercury ( β = 2.97; 95% CI, 1.49 to 4.44), with eGFR in postmenopausal women. Inverse associations of lead with eGFR in both premenopausal women ( β = -4.75; 95% CI, -6.04 to -3.46) and postmenopausal women ( β = -4.54; 95% CI, -6.96 to -2.13). Interactions were identified between lead and mercury, as well as cadmium and lead for eGFR among premenopausal women ( β = -2.04; 95% CI, -2.98 to -1.10) and postmenopausal women ( β = -3.52; 95% CI, -6.04 to -1.01), respectively. There was a negative association between mixed heavy metals and eGFR in both premenopausal women ( β = -2.23; 95% CI, -3.51 to -0.96) and postmenopausal women ( β = -3.86; 95% CI, -6.89 to -0.83). Lead was found as a key chemical related to reduced eGFR. Cutoff values for each heavy metal concentration related to eGFR were provided.

Postmenopausal women were more influenced by mixed heavy metals' effects on kidney function than premenopausal women. Early interventions (eg, water filtering, heavy metal yearly screening) in women, especially postmenopausal women, are needed to reduce the incidence of chronic kidney disease.