More than three million people in the U.S. each year are diagnosed with anemia. Previous research has shown that the condition is independently associated with increased mortality in patients with chronic kidney disease, heart failure and acute coronary syndromes.
A recent study found that the presence of anemia might also lead to worse outcomes for stroke patients. The meta-analysis, published in the Journal of the American Heart Association, included more than 29,000 adults who suffered strokes.
Among patients who had an ischemic stroke, the presence of anemia was associated with a 97 percent increased risk of mortality. Of those with a hemorrhagic stroke, the presence of anemia was associated with a 46 percent increased risk of mortality.
Although this meta-analysis included patients from various countries and high-quality studies, the researchers acknowledged more work needed to be done before determining how to treat patients with anemia following their strokes.
“The optimal treatment option in this patient group is unclear,” they wrote. “Studies are required to examine the clinical and cost-effectiveness of interventions in this patient population in an acute stroke setting.”
The results added to the conflicting literature on stroke and anemia, which is characterized by a lack of healthy red blood cells or hemoglobin in the blood. The researchers noted that some early studies found no association between anemia and stroke outcomes, while others found low and high hemoglobin levels were associated with increased mortality.
It’s also unclear whether interventions for patients with anemia would improve their outcomes following strokes. The researchers mentioned that one observational study found patients with anemia and hemorrhagic stroke benefited from packed red blood cell transfusions, while another found the transfusions did not help. They also could not identify any studies that have evaluated the effect of packed red blood cell transfusions on patients with anemia and ischemic stroke.
“Because of the paucity of evidence, guidelines have been unable to specify hemoglobin targets or optimal management options,” the researchers wrote. “A randomized controlled trial is required to gauge the impact of transfusions and to establish optimum hemoglobin ranges in patients with acute stroke.”