Inverse Association between T50 Calciprotein Crystallization (Serum Calcification Propensity) and Carotid Artery...

T50 is the time required for primary calciprotein particles (CPPs) to transform into secondary CPPs in vitro, reflecting serum calcification propensity, and used as a biomarker for calcification stress. Since secondary CPPs induce inflammation and oxidative stress, they may promote atherosclerosis. We investigated whether or not T50 was associated with carotid artery intima-media thickness (IMT).

This was a cross-sectional study of 202 health examinees. T50 was measured by the established nephelometric method. Carotid artery IMT was measured by high-resolution ultrasonography. The association between T50 and IMT was evaluated by a multivariable-adjusted linear regression analysis.

In a univariate analysis, IMT was not significantly correlated with T50. A multivariable-adjusted linear regression analysis showed that IMT was independently associated with age, sex, diabetes mellitus, dyslipidemia, and fetuin-A but not with T50 in the total subjects. However, when stratified by the estimated glomerular filtration rate (eGFR), T50 was independently and inversely associated with IMT in the subgroup with an eGFR ＜60 mL/min/1.73 m² (β = -0.418, P = 0.013), whereas it was not in the subgroup with an eGFR ≥ 60 mL/min/1.73 m².

T50 was independently and inversely associated with IMT in health examinees with a reduced kidney function, suggesting a novel link between calcification stress and atherosclerosis, particularly in those with chronic kidney disease.