Simultaneous Liver Kidney Transplant in Elderly Patients With Chronic Kidney Disease: Is There an Appropriate Upper Age Cutoff?

Background. The aging of liver transplant (LT) recipients, the weighting of the model for end-stage liver disease score, and the increased prevalence of nonalcoholic steatohepatitis has led to an increased number of older LT recipients with pre-LT chronic kidney disease (CKD). There are limited data on the impact of increased recipient age on post-simultaneous liver-kidney (SLK) transplant outcomes among patients with CKD, leading some centers to employ subjective age cutoffs for potential SLK recipients. Methods. We evaluated United Network for Organ Sharing data of adult SLK recipients from February 27, 2002, to December 31, 2018, restricted to recipients with >= 90 days of waiting time and CKD (estimated glomerular filtration rate persistently <60 mL/min/1.73 m2 for >= 90 d using the modification of diet in renal disease-4 equation). We fit mixed-effects Cox regression models (center as random effect) to evaluate the association of recipient age and patient survival. Results. Among 3146 SLK recipients with CKD, nearly two-thirds were 50-64 years of age, while 465 (14.8%) and 93 (3.0%) were 65-69 years and >= 70 years, respectively. Compared with nondiabetic SLK recipients aged 50-59 years, SLK recipients >= 70 years of age without diabetes (hazard ratio, 1.97; 95% CI, 1.20-3.23; P = 0.007) and with diabetes (hazard ratio, 1.90; 95% CI, 1.16-3.09; P = 0.01) had higher mortality compared with the reference group. In absolute terms, SLK recipients >= 70 years of age had 25% lower patient survival at 5 years compared to recipients aged 40-49 years. Conclusions. Although careful selection is required of any SLK recipient, especially those with increased comorbidities, there are no objective data to justify a specific age cutoff <70 years among potential SLK recipients with CKD.