CXCL12 and diabetes mellitus: Multivariable-adjusted spline regression models showed a linear association between SDF-1 levels and recurrent stroke (Fig. 1A, P for linearity = 0.005), cardiovascular events (Fig. 1C, P for linearity = 0.02), but not all-cause mortality (Fig. 1E, P for linearity = 0.09) at one year in patients with diabetes mellitus (Fig. 1).