# Prediction value of cystatin C for postoperative acute kidney injury of acute type A aortic dissection

## TL;DR

This study shows that preoperative cystatin C levels can predict acute kidney injury after aortic dissection surgery.

## Contribution

The study identifies cystatin C as an independent predictor of postoperative acute kidney injury in ATAAD patients.

## Key findings

- Preoperative cystatin C was significantly associated with postoperative AKI (OR: 11.541, P < 0.001).
- A clinical prediction model achieved a C-index of 0.804 in the training set.
- Cystatin C combined with other risk factors improves AKI prediction in ATAAD patients.

## Abstract

This study aimed to develop an early prediction model for postoperative acute kidney injury (AKI) in patients with acute type A aortic dissection (ATAAD) undergoing total a rch replacement (TAR) combined with frozen elephant trunk (FET) implantation. Specifically, it investigated the association between preoperative cystatin C levels and postoperative AKI while incorporating other relevant risk factors into the analysis.

A single-centre case-control study was conducted, including 202 patients treated between January 2018 and December 2019. Patients were divided into an AKI group (n=73) and a non-AKI group (n = 129) based on postoperative renal outcomes.

Univariate analysis revealed that a preoperative history of hypertension (P = 0.013), white blood cell (WBC) count (P&lt; 0.001), serum creatinine (P &lt; 0.001), blood urea nitrogen (P &lt; 0.001), and cystatin C (P&lt; 0.001) were significantly associated with postoperative AKI. Postoperative variables, including duration of mechanical ventilation (P&lt; 0.001), length of ICU stay (P&lt; 0.001), acute respiratory failure (P = 0 .0 1 8 ), acute cerebrovascular events (P= 0.042), and 30-day mortality (P&lt; 0.001) also differed significantly between groups. Multivariate logistic regression incorporating preoperative variables identified cystatin C (OR: 11.541, 95% CI: 3.811 -34.953 , P&lt; 0.001), WBC count (OR: 1.122, 95% CI: 1.013-1.242, P= 0.028), and history of hypertension (OR: 3.080, 95% CI: 1.188-7.990) as independent risk factors for postoperative AKI. Survival analysis further confirmed a significant association between preoperative cystatin C levels and the incidence of AKI in both crude and subgroup analyses. A clinical prediction model was developed based on the multivariate results. Internal validation showed a concordance index (C-index) of 0.804 for the training set and 0.609 for the validation set.

Preoperative cystatin C level was identified as an independent predictor of postoperative AKI. Incorporating cystatin C with other preoperative clinical risk factors may enhance the predictive accuracy for postoperative AKI in patients with ATAAD undergoing total arch replacement with FET implantation.