Center Variation in Intention-to-Treat Survival Among Patients Listed for Liver Transplant.

ABSTRACT

In the United States, centers performing liver transplant (LT) are primarily evaluated by patient survival within 1 year after LT, but tight clustering of outcomes allows only a narrow window for evaluation of center variation for quality improvement. Alternate measures more relevant to patients and the transplant community are needed. We examined adults listed for LT in the United States, using data submitted to the Scientific Registry of Transplant Recipients. Intention-to-treat (ITT) survival was defined as survival within 1 year from listing, regardless of transplant. Mixed effects/frailty models were used to assess center variation in ITT survival. Between January 2010 and December 2016, there were 66,428 new listings at 113 centers. Overall, median 1-year ITT survival was 79.8% (interquartile range [IQR], 76.1%-83.4%), whereas 1-year waiting-list (WL) survival was 75.8% (IQR, 71.2%-79.4%), and 1-year post-LT survival was 90.0% (IQR, 87.9%-91.8%). Higher rates of ITT mortality were correlated with increased WL mortality (correlation, r = 0.76), increased post-LT mortality (r = 0.31), lower volume centers (r = -0.34), and lower transplant rate ratio (r = -0.25). Similar patterns were observed in the subgroup of WL candidates listed with Model for End-Stage Liver Disease (MELD) ≥25 median 1-year ITT survival was 65.2% (IQR, 60.2%-72.6%), whereas 1-year post-LT survival was 87.5% (IQR, 84.0%-90.9%), and 1-year WL survival was 36.6% (IQR, 27.9%-47.0%). In mixed effects modeling, the transplant center was an independent predictor of ITT survival even after adjustment for age, sex, MELD, and sociodemographic variables. Center variation for ITT survival was larger compared with post-LT survival. The measurement of ITT outcome offers a complementary method to assess center performance. This is a first step toward understanding differences in program quality beyond patient and graft survival after LT.