Metals in urine and diabetes in U.S. adults

Our objective was to evaluate the relationship of urine metals including barium, cadmium, cobalt, cesium, molybdenum, lead, antimony, thallium, tungsten, and uranium with diabetes prevalence. Data were from a cross-sectional study of 9,447 participants of the 1999-2010 National Health and Nutrition Examination Survey, a representative sample of the U.S. civilian noninstitutionalized population. Metals were measured in a spot urine sample, and diabetes status was determined based on a previous diagnosis or an A1C ≥6.5% (48 mmol/mol). After multivariable adjustment, the odds ratios of diabetes associated with the highest quartile of metal, compared with the lowest quartile, were 0.86 (95% CI 0.66-1.12) for barium (P_trend = 0.13), 0.74 (0.51-1.09) for cadmium (P_trend = 0.35), 1.21 (0.85-1.72) for cobalt (P_trend = 0.59), 1.31 (0.90-1.91) for cesium (P_trend = 0.29), 1.76 (1.24-2.50) for molybdenum (P_trend = 0.01), 0.79 (0.56-1.13) for lead (P_trend = 0.10), 1.72 (1.27-2.33) for antimony (P_trend < 0.01), 0.76 (0.51-1.13) for thallium (P_trend = 0.13), 2.18 (1.51-3.15) for tungsten (P_trend < 0.01), and 1.46 (1.09-1.96) for uranium (P_trend = 0.02). Higher quartiles of barium, molybdenum, and antimony were associated with greater HOMA of insulin resistance after adjustment. Molybdenum, antimony, tungsten, and uranium were positively associated with diabetes, even at the relatively low levels seen in the U.S. population. Prospective studies should further evaluate metals as risk factors for diabetes.