Delayed platelet recovery after allogeneic hematopoietic stem cell transplantation: Association with chronic graft‐versus‐host disease and survival outcome

Abstract Delayed platelet recovery (DPR) despite prompt neutrophil engraftment is frequently observed after allogeneic hematopoietic stem cell transplantation (HSCT). However, few studies have evaluated the risk factors and long‐term outcome. Therefore, we retrospectively analysed 219 adult patients who underwent their first allogenic HSCT with neutrophil engraftment. Of these 219 patients, 50 (22.8%) had DPR that was defined as relapse‐free survival at day 60 after HSCT without primary platelet recovery despite neutrophil engraftment. The results of a multivariate analysis showed that a high‐risk underlying disease (odds ratio [OR], 2.38; 95% confidence interval [CI], 1.04‐5.48; P = .041) and human leukocyte antigen–mismatched HSCT (OR, 2.63; 95% CI, 1.28‐5.43; P = .009) were associated with an increased risk of DPR. In univariate analyses, the occurrence of DPR was significantly associated with inferior overall survival, high nonrelapse mortality, and a low incidence of chronic graft‐versus‐host disease (GVHD), despite a comparable relapse rate. In multivariate analyses, DPR was associated with inferior overall survival (hazard ratio [HR], 2.00; 95% CI, 1.23‐3.27; P = .005) and a low incidence of chronic GVHD (HR, 0.42; 95% CI, 0.22‐0.78; P = .002). In conclusion, DPR was a strong predictor of shorter survival but also less frequent chronic GVHD.