Variability in serum creatinine is associated with waitlist and post-liver transplant mortality in patients with cirrhosis

Background and Aims Kidney function in patients with cirrhosis is dynamic. After controlling for the presence of chronic kidney disease (CKD) and acute kidney injury (AKI), we investigated the impact of variation in clinical function on pre-liver transplantation (LT) and post-LT outcomes. Approach and Results We included adults listed for LT from 2011 through 2018. We excluded those with any exceptions, those on hemodialysis at listing, and those with fewer than three clinical updates in the United Network for Organ Sharing database. Our primary exposure was the serum creatinine coefficient of variation (sCr CoV). Logistic regression determined the associations between our exposures and higher sCr CoV. Competing risk regression determined the associations between our exposures and waitlist mortality, accounting for LT as a competing risk. Cox regression determined the associations between our exposures and either listing for kidney transplant or death. We divided our cohort into tertiles of sCr CoV: low variability, 8.8% (interquartile range [IQR], 6.6%-10.8%); intermediate variability, 17.4% (IQR, 14.8%-20.4%); high variability, 36.8% (IQR, 29.5%-48.8%). We demonstrate that women, those with CKD, and those with advanced liver disease were more likely to have a greater sCr CoV. Compared to those with low variability, those with high variability had significantly higher waitlist mortality (34.7% vs. 19.6% vs. 11.7%, p < 0.001). We highlight that the sCr CoV was associated with higher waitlist and post-LT mortality-an association independent of baseline sCr, the degree of underlying liver disease, the presence of AKI, or the presence of CKD. Conclusion This study informs the long-term impact of the variation in kidney function we all see in clinical practice. These data highlight that all fluctuations in sCr are associated with worse pre-LT and post-LT outcomes.