Prognostic significance of preoperative nutritional status for heart transplantation patients

The association between malnutrition and outcomes of heart transplantation (HTx) has not been well studied. The purpose of this article was to evaluate the prognostic value of three different nutrition indices in HTx, including CONUT (Controlling Nutritional Status), NRI (Nutritional Risk Index) and GNRI (Geriatric Nutritional Risk Index).

A total of 438 patients who underwent THx from January 2015 to December 2020 were included in this study. The nutritional status of the patients was evaluated by CONUT, NRI and GNRI. Kaplan-Meier (KM) curves were constructed to compare the difference in overall survival (OS) between the normal and malnutrition groups in each index. Cox regression analysis was used to identify the independent risk factors of OS. The predictive power was compared by time-dependent ROC and time-dependent ccurves. Logistic regression model was used to evaluate the relationship between these three nutrition indices and postoperative clinical events.

336 (76.7%), 183 (43.8%), and 190 (43.4%) patients had malnutrition according to CONUT, NRI and GNRI calculations. 102 (23.3%) patients had died at the end of follow-up. After adjustment for confounding variables, multivariate Cox analysis showed that CONUT [HR 1.286 (95%CI 1.166 ~ 1.419); p < 0.001], NRI [HR 0.942 (95%CI 0.923 ~ 0.962); p < 0.001] and GNRI [HR 0.959 (95%CI 0.939 ~ 0.979); p < 0.001] were all independent predictors for OS. The predictive power of CONUT score was higher than that of NRI (p = 0.045) and GNRI (p < 0.001). Regarding the postoperative complications, multivariate logistic regression model showed that malnutrition assessed by CONUT [HR 1.156 (95%CI 1.032 ~ 1.294); p = 0.012] and NRI [HR 1.543 (95%CI 1.008 ~ 2.362); p = 0.046] was independent risk factors for posttransplant infections.

Poor nutritional status, as assessed by CONUT, NRI and GNRI, was associated with an increased risk of mortality after HTx. CONUT displayed the highest predictive power compared to the other two indices. CONUT and NRI were also independently associated with posttransplant infections.