Urinary excretion of chromium, copper, and manganese in diabetes mellitus and associated disorders.

The urinary excretion of chromium, copper and manganese was determined in 185 diabetics and in an equal number of control subjects by measuring the concentration of each of these metals using electrothermal atomic spectrophotometry and dividing the values by the urinary concentration of creatinine (creat) in each subject. The mean (SEM) values for the overall diabetics and the control group were 2.32 (0.17) and 2.62 (0.22) mumol Cr/mole of creat, 76.5 (5.5) and 73.9 (6.1) mumol Cu/mole of creat, and 3.56 (0.44) and 2.66 (0.3) mumol Mn/mole of creat, respectively. There was no correlation between the urinary excretion of any of the metals examined and age or sex of either group. While the cardiovascular or ophthalmologic diseases associated with diabetes did not influence the excretion of any of these metals, significantly higher urinary excretion of Cu was exhibited by diabetics with neuropathy (p < 0.0027) or infections (p < 0.014) than by those without. Also, diabetics with liver disorders or those who were not treated with insulin excreted significantly more Mn than did their diabetic counterparts.