Changing age distribution of the blood donor population in the United States.

BACKGROUND: The American Red Cross has been maintaining a research database of all blood donors. Such a database provides a unique opportunity for monitoring changes over time in donor and donation patterns. STUDY DESIGN AND METHODS: Changes in age distribution among blood donors were analyzed through comparison of the volunteer donor population in 1996, 1999, 2002, and 2005, before and after adjustment for demographic changes of the general population in the United States.
RESULTS: Donations by repeat donors 50 years or older as a proportion of total donations increased from 22.1 percent in 1996 to 34.5 percent in 2005, or 1.4 percent per year, whereas donations from repeat donors of 25 to 49 years decreased from 49.1 percent in 1996 to 37.1 percent in 2005, or 1.3 percent per year. After adjusting for general population trends, the effective number of donors decreased by more than 10 percent in female and male repeat donors of age 20 to 49 years and male first-time donors of age 25 to 49 years from 1996 to 2005; female and male repeat donors of age 25 to 39 years decreased by greater than 40 percent. Prevalence rates of major infectious disease markers decreased by 3.3 percent or more per year for first-time donations and by 6.4 percent or more per year for repeat donations.
CONCLUSION: The aging patterns of blood donors suggest the need for improved recruitment and retention in the young adult and middle-aged groups. A severe shortage of blood and blood components may be forecast in the foreseeable future unless offset by significant increased supply or reduced usage of blood and blood components.