Given that age was a major predisposing factor for prognosis of ischemic stroke and serum Dkk-3 level was positively related to age in this study and the previous study [9], we adjusted age in the multivariable Cox proportional hazards regression model and performed further subgroup analysis stratified by age to weaken or even eliminate the confounding effects of age on the association between serum Dkk-3 and prognosis of ischemic stroke. Here, DKK3 is linked to ischemic stroke.