Inverse correlations between age and the M value (A), between age and NOx FSR (B), and between age and either ADMA (C) or SDMA (D) concentrations. Inverse correlations between age and the M value (A), between age and NOx FSR (B), and between age and either ADMA (C) or SDMA (D) concentrations. A two-order polynomial model was used for the correlation analysis and the linear fit. The multiple R2 regression values are reported. The P values for significance are also reported. Paolo Tessari et al. Diabetes 2013;62:2699-2708 ©2013 by American Diabetes Association