Cause‐specific mortality associated with leukoreduced, buffy coat–depleted, or no blood transfusion after elective surgery for colorectal cancer: a posttrial 15‐year follow‐up study

Abstract

We previously reported that both leukoreduced (LR) and buffy coat-depleted (BCD) blood transfusions had a detrimental effect on long-term overall survival in patients who underwent elective surgery for colorectal disease. This analysis investigates long-term cause-specific mortality in trial participants diagnosed with colorectal cancer (CRC). We used the Danish Civil Registration System to follow 448 trial participants with CRC, from their enrollment in 1992 to 1995 until January 2007. A total of 108 patients were transfused with BCD blood, 94 with LR blood, and 246 did not receive a transfusion (NT). We reviewed death certificates for study patients who died during follow-up. Cause-of-death data were coded according to the International Classification of Diseases (ICD-8 and -10). The Charlson Comorbidity Index was used for risk adjustment. A total of 43% of NT, 28% of BCD, and 27% of LR transfused patients were alive after 15 years of follow-up (p = 0.001 for transfused vs. NT patients). For LR-transfused versus NT patients the adjusted mortality ratio for death from rectal cancer was 1.81 (95% confidence interval [CI], 0.97-3.38), and for death from cardiovascular disease 2.12 (95% CI, 1.23-3.62). For BCD versus NT patients the adjusted mortality ratio for death from rectal cancer was 1.19 (95% CI, 0.61-2.33) and for cardiovascular disease it was 1.68 (95% CI, 0.97-2.91). LR transfusion is associated with decreased long-term survival due to death from cardiovascular disease. A similar but weaker tendency was observed for BCD transfusion.