Reduction of Arterial Stiffness After Kidney Transplantation: A Systematic Review and Meta‐Analysis

BACKGROUND: End‐stage kidney disease is associated with increased arterial stiffness. Although correction of uremia by kidney transplantation (KTx) could improve arterial stiffness, results from clinical studies are unclear partly due to small sample sizes. METHOD AND RESULTS: We conducted a systematic review and meta‐analysis of before‐after design studies performed in adult KTx patients with available measures of arterial stiffness parameters (pulse wave velocity [PWV], central pulse pressure [PP], and augmentation index) before and at any time post‐KTx. Mean difference of post‐ and pre‐KTx values of different outcomes were estimated using a random effect model with 95% confidence interval. To deal with repetition of measurement within a study, only 1 period of measurement was considered per study by analysis. Twelve studies were included in meta‐analysis, where a significant decrease of overall PWV by 1.20 m/s (95% CI 0.67‐1.73, I(2)=72%), central PWV by 1.20 m/s (95% CI 0.16‐2.25, I(2)=83%), peripheral PWV by 1.17 m/s (95% CI 0.17‐2.17, I(2)=79%), and brachial‐ankle PWV by 1.21 m/s (95% CI 0.66‐1.75, I(2)=0%) was observed. Central PP (reported in 4 studies) decreased by 4.75 mm Hg (95% CI 0.78–10.28, I(2)=50%). Augmentation index (reported in 7 studies) decreased by 10.5% (95% CI 6.9‐14.1, I(2)=64%). A meta‐regression analysis showed that the timing of assessment post‐KTx was the major source of the residual variance. CONCLUSIONS: This meta‐analysis suggests a reduction of the overall arterial stiffness in patients with end‐stage kidney disease after KTx.