Renal Decline Following Lung Transplant

Purpose Renal decline is common after organ transplant and is often attributed to nephrotoxic immunosuppression drugs. We aim to assess for additional risk factors of renal decline and the impact on survival following lung transplant. Methods This was a retrospective review from 2012-2018. Patients under age 18 and with missing creatinine data were excluded. The glomerular filtration rate (GFR) was estimated using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation. Postoperative acute kidney injury (AKI) and chronic kidney disease (CKD) were calculated by the Kidney Disease Improving Global Outcomes (KDIGO) criteria and CKD Staging System, respectively. The primary outcome was renal decline at one year. Renal decline was defined as the development of CKD or progression in stages for those with underlying CKD. Results A total of 471 patients met inclusion criteria, with an overall 30-day mortality rate of 2.1% (n=10). There were 224 (47.6%) patients that experienced an AKI in the immediate post-operative period: 145 KDIGO Stage 1 (30.8%), 52 KDIGO Stage 2 (11.0%), and 27 KDIGO Stage 3 (5.7%). The overall rate of renal decline within one year was 47% (n=222). In total, 23 (4.9%) patients required hemodialysis at one year. Predictors of renal decline were age (HR 1.06; 95% CI 1.04-1.08), male sex (HR .42; 95% CI .28-.65), eGFR (HR .98; 95% CI .98-.99), and AKI (1.71; 95% CI 1.12-2.59). Renal decline was not associated with long-term mortality on Cox regression. There was no difference in long-term mortality between patients who did and did not experience renal decline (Figure 1A). When stratified by CKD stages at one year post operatively, only CKD stage 5 was associated with long-term mortality (Figure 1B). Conclusion Renal decline is common after lung transplantation but is not associated with long-term mortality except in its most severe form.