The impact of platelet transfusion characteristics on posttransfusion platelet increments and clinical bleeding in patients with hypoproliferative thrombocytopenia

Abstract

Platelet characteristics, such as platelet dose, platelet source (apheresis vs pooled), platelet donor-recipient ABO compatibility, and duration of platelet storage, can affect posttransfusion platelet increments, but it is unclear whether these factors impact platelet transfusion efficacy on clinical bleeding. We performed secondary analyses of platelet transfusions given in the prospective randomized Platelet Dose Study, which included 1272 platelet-transfused hematology-oncology patients who received 6031 prophylactic platelet transfusions. The primary outcome of these analyses was time from first transfusion to first World Health Organization ≥ grade 2 bleeding. Platelet transfusion increments were assessed at 0.25 to 4 hours and 16 to 32 hours after platelet transfusion. There were 778 patients evaluable for analysis of time to bleeding. Adjusted models showed that randomized dose strategy, platelet source, ABO compatibility, and duration of storage did not predict this outcome. Platelet increments were generally higher for transfusions of apheresis platelets, ABO-identical platelets, and platelets stored 3 days versus 4 to 5 days. Thus, although platelet source, ABO compatibility, and duration of storage exert a modest impact on both absolute and corrected posttransfusion platelet increments, they have no measurable impact on prevention of clinical bleeding. This trial was registered at www.clinicaltrials.gov as #NCT00128713.

Figures

Figure 1

Kaplan-Meier plots of time from platelet transfusion to first ≥ grade 2 bleeding for each platelet characteristic. (A) Time from first platelet transfusion to first grade 2 or higher bleeding by platelet dose group. Time to bleeding was censored at the first date that any of the following occurred: missing data on whether ≥ grade 2 bleeding occurred; or end of study. Divergence of the curves after 24 days is probably the result of the small number of patients still at risk by that time. Platelet dose group was not a significant predictor of time to ≥ grade 2 bleeding (P = .77). (B) Time from first platelet transfusion to first grade 2 or higher bleeding by source of platelets. Time to bleeding was censored at the first date that any of the following occurred: transfusion of a platelet unit with a different source from the patient's initial platelet transfusion; missing data on whether ≥ grade 2 bleeding occurred; or end of study. Platelet source was not a significant predictor of time to ≥ grade 2 bleeding (P = .44). (C) Time from first platelet transfusion to first grade 2 or higher bleeding by ABO matching status. Time to bleeding was censored at the first date that any of the following occurred: transfusion of a platelet dose with a different ABO matching status from the patient's initial platelet transfusion or missing data on ABO matching status; missing data on whether ≥ grade 2 bleeding occurred; or end of study. Divergence of the curves after 15 days is probably the result of the small number of patients still at risk by that time. ABO matching status was not a significant predictor of time to ≥ grade 2 bleeding (P = .33). (D) Time from first platelet transfusion to first grade 2 or higher bleeding, by platelet storage duration, among patients whose first platelet transfusion was stored for 0 to 5 days. Time to bleeding was censored at the first date that any of the following occurred: transfusion of a platelet unit with a different storage duration from the patient's initial platelet transfusion; transfusion of a platelet unit with missing data on storage duration; transfusion of pooled WBP platelets of different storage durations; missing data on whether ≥ grade 2 bleeding occurred; or end of study. Divergence of the curves after 10 days is probably the result of the small number of patients still at risk by that time. Duration of platelet storage was not a significant predictor of time to ≥ grade 2 bleeding (P = .87).

Figure 2

Multipredictor model of the effects of platelet dose, source, storage duration, and ABO matching status on 4-hour ABSOLUTE platelet count increment. The model also adjusts for transfusion number, patient sex, patient age group, patient treatment stratum, and within-site and within-person correlation. Data shown are the adjusted means and 95% confidence intervals. N = number of prophylactic platelet transfusions analyzed.

Figure 3

Multipredictor model of the effects of platelet dose, source, storage duration, and ABO matching status on 4-hour CORRECTED platelet count increment. The model also adjusts for transfusion number, patient sex, patient age group, patient treatment stratum, and within-site and within-person correlation. Data shown are the adjusted means and 95% confidence intervals. N = number of prophylactic platelet transfusions analyzed.

Figure 4

Multipredictor model of the effects of platelet dose, source, storage duration, and ABO matching status on 24-hour ABSOLUTE platelet count increment. The model also adjusts for transfusion number, patient sex, patient age group, patient treatment stratum, and within-site and within-person correlation. Data shown are the adjusted means and 95% confidence intervals. N = number of prophylactic platelet transfusions analyzed.

Figure 5

Multipredictor model of the effects of platelet dose, source, storage duration, and ABO matching status on 24-hour CORRECTED platelet count increment. The model also adjusts for transfusion number, patient sex, patient age group, patient treatment stratum, and within-site and within-person correlation. Data shown are the adjusted means and 95% confidence intervals. N = number of prophylactic platelet transfusions analyzed.