Postoperative acute kidney injury and early and long-term mortality in acute aortic dissection patients: A meta-analysis

OBJECTIVE: To evaluate the impact of postoperative acute kidney injury (AKI) on early and long-term mortality in patients with acute aortic dissection by conducting a meta-analysis. METHODS: An extensive literature search was performed in PubMed and Embase databases until February 15, 2020. Observational studies that reported the associations between postoperative AKI and early (in-hospital and within 30 days) or long-term mortality in patients with acute aortic dissection were included. RESULTS: Seven studies comprising 1525 acute aortic dissection patients were identified. A random effect meta-analysis showed that postoperative AKI was significantly associated with higher risk of long-term mortality (risk ratio [RR] 2.32; 95% confidence interval [CI] 1.50–3.59). Subgroup analysis revealed that the pooled RR of long-term mortality was 1.42 (95% CI 0.90–2.22) for stage 1 AKI, 1.72 (95% CI 0.95–3.12) for stage 2 AKI, and 4.46 (95% CI 2.72–7.32) for stage 3 AKI, respectively. Furthermore, postoperative stage 3 AKI was associated with an increased risk of early mortality (RR 11.3; 95% CI 4.2–30.5). CONCLUSIONS: This meta-analysis provided clinical evidence that postoperative stage 3 AKI is associated with higher risk of early and long-term mortality, even after adjusting important confounding factors. However, the current findings should be interpreted with caution due to the retrospective nature and limited number of studies analyzed.