Cadmium exposure induces hematuria in Korean adults

• A high level of blood cadmium is associated with a high risk of hematuria.
• This correlation is independent of several confounding factors.
• Blood levels of lead and mercury are not associated with risk of hematuria.
• This is the first study on the correlation between cadmium exposure and hematuria risk.

IntroductionToxic heavy metals have adverse effects on human health. However, the risk of hematuria caused by heavy metal exposure has not been evaluated.MethodsData from 4701 Korean adults were obtained in the Korean National Health and Nutritional Examination Survey (2008–2010). Blood levels of the toxic heavy metals cadmium, lead, and mercury were measured. Hematuria was defined as a result of ≥+1 on a urine dipstick test. The odds ratios (ORs) for hematuria were measured according to the blood heavy metal levels after adjusting for multiple variables.ResultsIndividuals with blood cadmium levels in the 3rd and 4th quartiles had a greater OR for hematuria than those in the 1st quartile group: 3rd quartile, 1.35 (1.019–1.777; P=0.037); 4th quartile, 1.52 (1.140–2.017; P=0.004). When blood cadmium was considered as a log-transformed continuous variable, the correlation between blood cadmium and hematuria was significant: OR, 1.97 (1.224–3.160; Ptrend=0.005). In contrast, no significant correlations between hematuria and blood lead or mercury were found in the multivariate analyses.DiscussionThe present study shows that high cadmium exposure is associated with a risk of hematuria.