Red blood distribution width and heart transplantation: any predictive role on patient outcome?

Red blood cell distribution width (RDW) has been emerging as a strong predictor of mortality among patients with cardiovascular disease. The aim of this study was to verify if RDW is able to predict survival after heart transplantation (HTx).

Two hundred and eighteen recipients who underwent HTx between 2000 and 2013 were classified into three groups according to the pre-HTx RDW tertile values (14.6 and 16.4%), and their outcomes were compared. Mean follow-up was 6.6 ± 4.2 years.

RDW correlated with other markers of chronic pathological conditions, such as the Index for Mortality Prediction after Cardiac Transplantation (IMPACT) score (P = 0.002) and Charlson Comorbidity Index (P < 0.001), and with creatinine levels (P = 0.007), previous cardiac surgery (P < 0.001), diabetes mellitus (P = 0.02), haemoglobin value (P = 0.004), pulmonary capillary wedge and central venous pressures (P = 0.019 and 0.01, respectively), systolic and mean pulmonary artery pressures (P = 0.002 and 0.014, respectively). The rate of 30-day mortality from the lowest to the highest RDW tertile was 1.4, 4 and 9% (P = 0.02), respectively.Long-term mortality correlated at multivariate analysis with recipient age [hazard ratio 1.06, 95% confidence interval (95% CI) 1.02-1.09], donor age (hazard ratio 1.02, 95% CI 1.0-1.04) and RDW (hazard ratio 1.13, 95% CI 1.04-1.23). The survival probability at 4, 8 and 12 years was 90, 84 and 74% for recipients with RDW less than 14.6%, while it was 72, 60 and 42% for recipients with RDW more than 16.4% (hazard ratio 3.29, 95% CI 1.74-6.24). No differences were found between causes of death.

RDW correlated with survival in HTx recipients. This marker of blood cell size may represent a surrogate of disease and a helpful tool in the risk-assessment process.