Long-term survival after blood transfusion

Area of Science:

• Transfusion Medicine
• Epidemiology
• Public Health

Background:

• Previous studies indicated high posttransfusion mortality rates (over 50% within 2 years) in tertiary care hospital populations during the 1980s.
• A need existed to quantify the association between blood transfusion and mortality in a broader, general population.

Purpose of the Study:

• To determine the association between blood transfusion and mortality in a general county population.
• To quantify the dose-response relationship between blood components and subsequent survival.

Main Methods:

• A retrospective cohort study was conducted on 802 county residents who received blood transfusions in 1981.
• Complete follow-up data (until death or 10 years) was obtained for 93.9% of the cohort.
• Statistical analysis adjusted for age, gender, and hospitalization duration.

Main Results:

• The median survival was 95 months, with 52% mortality within 10 years post-transfusion.
• A significant dose-response relationship was observed: relative risk of death increased by 4.1% per unit of red cells, 1.2% per unit of platelets, and 7.3% per unit of fresh-frozen plasma.
• Blood transfusion independently predicted mortality, adding to the predictive value of age, gender, and prior hospitalization.

Conclusions:

• Blood transfusion receipt is an independent predictor of mortality in the general population, serving as an epidemiologic index of morbidity.
• A clear dose-response relationship exists between the volume of blood components transfused and reduced survival length.
• Posttransfusion mortality in a general population study is lower than previously reported in tertiary care look-back investigations.