Zinc As A Factor Affecting Serum Calcification Propensity in Patients With Type 2 Diabetes Mellitus

Abstract Background : Zinc inhibits vascular calcification in vivo and in vitro . Patients with type 2 diabetes mellitus show hypozincemia and are at an elevated risk of cardiovascular events. Recently, the in vitro test (T 50 -test) was developed for the determination of serum calcification propensity. This cross-sectional study investigated the association between serum zinc and T 50 in type 2 diabetes mellitus patients and the effect of zinc on T 50 in vitro. Methods : The subjects were 132 type 2 diabetes mellitus patients with various kidney function. We measured T 50 levels by the established nephelometric method. Results : The median (interquartile range) levels of T 50 and serum zinc were 306 (269 to 332) min, and 80.0 (70.1 to 89.8) µg/dL, respectively. Serum zinc level was significantly and positively correlated with T 50 (r s = 0.219, p = 0.012). This association remained significant in multivariable-adjusted analysis, and was independent of known factors including phosphate, calcium, and magnesium. Renal function and glycemic control were not significantly associated with T 50 . Finally, addition of physiological concentration of exogenous zinc chloride significantly increased the serum T 50 i n vitro . Conclusions : This is the first report to investigate the association between serum calcification propensity and zinc levels in type 2 diabetes mellitus patients. Our data suggest that serum zinc is an independent factor that inhibits serum calcification propensity .