Vascular age is associated with the risk of dialysis or death in chronic kidney disease

Increased arterial stiffness is associated with progressive renal deterioration and poor clinical outcomes in patients with chronic kidney disease (CKD). Assessment of vascular age as derived from arterial stiffness parameters might be an important clinical marker of cardiovascular risks. The aim of the present study is to evaluate whether the difference (△age) between vascular age and chronological age can predict the risk of reaching dialysis or death in patients with known CKD.

This longitudinal study enrolled 94 male Chinese CKD patients, aged 40-62 years. Vascular age was calculated by brachial-ankle pulse wave velocity, and measured by an ankle-brachial index-form device. The study endpoints were the commencement of renal replacement therapy or death.

After a stepwise multivariate analysis, △age was associated independently with increased urine protein-to-creatinine ratio (β = 0.32; P = 0.001) and decreased baseline estimated glomerular filtration rate (β = -0.24; P = 0.008). During a median follow-up period of 62 (interquartile range = 55-66) months, the 4-year cumulative incidence of reaching the study endpoint in patients with △age = 0 and △age > 0 year was 4.9% and 25%, respectively (log-rank test, P = 0.009). Multivariate forward Cox regression analysis identified that higher △age (hazard ratio (HR) = 1.05; P = 0.027), lower baseline estimated glomerular filtration rate (HR = 0.93; P < 0.001), and history of cardiovascular disease (HR = 5.90; P = 0.031) were independently associated with progression to commencement of dialysis or death.

Thus, the assessment of the difference between vascular age and chronological age may provide an alternative method to identify CKD patients at a high risk of progression to dialysis or death.