RESUMEN
BACKGROUND: There is debate whether delayed umbilical cord clamping following delivery, the current gold standard, affects the proportion of cord blood units (CBU) suitable for public cord blood banking. This study was designed to assess the impact of delayed cord clamping on the number of CBU suitable for therapeutic uses. MATERIALS AND METHODS: To minimize variability, data from the four most active collection centers within the Programa Concordia (Spain) were included. Data on CBU collected in utero from mothers following normal vaginal deliveries from July 2018 to December 2021 were analyzed. The weight of the collection bags (as a surrogate of volume) and total nucleated cell (TNC) count were analyzed according to three defined clamping times: 30 s, 60 s and ≥120 s. The CBU were stratified as suitable for stem cell transplantation (≥110 g and ≥1,500×106 TNC/unit) or other clinical applications (≥100 g but TNC count below the threshold). RESULTS: - There were 131 (18%), 548 (76%), and 40 (5%) CBU collected at 30 s, 60 s and ≥120 s, respectively. The median weight of the CBU decreased gradually with time, with a significant difference between units collected when the cord was clamped at 30 s or 60 s (p=0.036), so significantly fewer CBU met the minimal weight criterion (100 g) at 60 s than at 30 s (p=0.002). However, this was not reflected by the TNC available, resulting in non-statistical differences in CBU eligible for banking between these times. The major predictor of collection success was the neonate's birth-weight. DISCUSSION: -Despite decreases in the volume of cord blood collected when cord clamping at 30 s or 60 s, TNC count is maintained resulting in similar numbers of CBU eligible for banking. The different clamping delays investigated in this study are, therefore, compatible with public cord blood banking needs.
RESUMEN
Individual comorbidities have distinct contributions to nonrelapse mortality (NRM) following allogeneic hematopoietic cell transplantation (allo-HCT). We studied the impact of comorbidities individually and in combination in a single-center cohort of 573 adult patients who underwent CD34-selected allo-HCT following myeloablative conditioning. Pulmonary disease, moderate to severe hepatic comorbidity, cardiac disease of any type, and renal dysfunction were associated with increased NRM in multivariable Cox regression models. A Simplified Comorbidity Index (SCI) composed of the 4 comorbidities predictive of NRM, as well as age >60 years, stratified patients into 5 groups with a stepwise increase in NRM. NRM rates ranged from 11.4% to 49.9% by stratum, with adjusted hazard ratios of 1.84, 2.59, 3.57, and 5.38. The SCI was also applicable in an external cohort of 230 patients who underwent allo-HCT with unmanipulated grafts following intermediate-intensity conditioning. The area under the receiver operating characteristic curve (AUC) of the SCI for 1-year NRM was 70.3 and 72.0 over the development and external-validation cohorts, respectively; corresponding AUCs of the Hematopoietic Cell Transplantation-specific Comorbidity Index (HCT-CI) were 61.7 and 65.7. In summary, a small set of comorbidities, aggregated into the SCI, is highly predictive of NRM. The new index stratifies patients into distinct risk groups, was validated in an external cohort, and provides higher discrimination than does the HCT-CI.