Anemia in Heart Patients Linked to Hospital Blood Tests: Study

A new study suggests that repeated blood tests on some hospital patients may increase the risk of developing anemia. 

Researchers found that the more blood that was taken from heart attack victims during their hospital stay, the more likely they were to develop anemia. The findings were reported in a study published online by the Archives of Internal Medicine.

The study looked at data from 17,676 heart attack patients from 2000 to 2008 in 57 hospitals in the United States. Moderate to severe hospital-acquired anemia developed in 20% of those patients. The patients who developed anemia tended to have more than 174 mL of blood drawn, while those who did not develop anemia or developed mild cases lost less blood.

The amount of blood drawn in the victims who developed moderate to severe anemia was equivalent to nearly half a unit of blood (a little less than one pint), the researchers reported. More than 12% of the subjects of the study had much higher blood loss; over 300 mL. The majority of the blood loss came in the first two days patients were hospitalized.

The researchers said the findings have important clinical implications, as some of the blood loss is likely preventable and reducing the amount drawn could have a positive health impact on patients. They called for further studies to look at shoring up the likelihood that minimizing blood loss due to diagnostic tests improved patient health.

Anemia involves a lack or reduction of red blood cells or hemoglobin in the blood. Hemoglobin carries oxygen throughout the body. Both chronic and hospital-acquired anemia has been associated with decreased health and increased risk of death among heart attack patients, according to the researchers involved with the study.