Table 3.

Short- and long-term relative risk of death following blood transfusion in relation to storage age of administered red-cell concentrates, among recipients of leukocyte depleted units only.

	Day 1 through 7		Day 8 through 730
Storage age	Events/ Person yrs	Hazard ratio (95% CI)*	Events/ Person yrs	Hazard ratio (95% CI)*
0-9 days	768/504	0.88 (0.79-0.97)	2,691/26,778	0.98 (0.94-1.02)
10-19 days	750/473	1.00 (ref)	2,379/20,152	1.00 (ref)
20-29 days	280/189	0.94 (0.82-1.08)	847/6,768	0.96 (0.90-1.02)
30-42 days	182/105	1.10 (0.93-1.31)	481/3,587	1.00 (0.93-1.08)
Mixed age	421/194	0.96 (0.84-1.09)	1,706/17,836	1.00 (0.95-1.04)

CI denotes confidence interval.

^*Estimated using Cox proportional hazards regression, adjusted for number of transfusions, age, sex, blood group, calendar period, season, weekday, hospital and indication.