Older adults with anemia may have a higher risk of dying after a stroke, according to new research.

Anemia, a lack of red blood cells, is common in patients with acute stroke. Anemia and low hemoglobin levels, proteins in red blood cells that carry oxygen throughout the body, are also common in older people.

Examining data of 8,013 acute stroke patients from 2003 to 2015, researchers assessed the impact of anemia and hemoglobin levels on death at different times up to one year following a stroke. They found that anemia was present in about a quarter of patients with stroke upon admission and was associated with a higher risk of death for up to one year after a clot-caused ischemic stroke or a hemorrhagic stroke caused by a ruptured blood vessel.

Elevated hemoglobin levels were also associated with poorer outcomes and a higher risk of death, mainly within the first month following a stroke.

“We found that the likelihood of dying from ischemic stroke is about two times higher in people with anemia compared to those without it, and the risk of death from hemorrhagic stroke is about one-and-a-half times higher,” said Phyo Myint, M.D., senior study author and professor of medicine of old age at the University of Aberdeen in Scotland. “So there’s the potential for a much poorer outcome if somebody comes in with stroke and they’re also anemic.”

The study reveals the need for increased awareness and interventions for stroke patients with anemia, said Raphae Barlas, coauthor of the study and a medical student at the University of Aberdeen.

“One example of an intervention might be treating the underlying causes of anemia, such as iron deficiency, which is common in this age group,” Barlas said. “As the study has convincingly demonstrated, anemia does worsen the outcome of stroke, so it is very important that we identify at-risk patients and optimize the management.”

The study published Wednesday in the Journal of the American Heart Association.