Researchers examined data on 17,676 patients admitted to 57 hospitals from January 1, 2000, through December 31, 2008. All patients had a diagnosis of acute MI; none had anemia at admission. The investigators found that more than 20% of patients developed moderate-to-severe hospital-acquired anemia (HAA), and the amount of blood taken for diagnostic purposes from these patients was about 90 mL greater than from those who didn't develop HAA