Anemic adults may have a higher risk of death after stroke

Anemic adults may have a higher risk of death after stroke

Anemia, a lack of red blood cells, may be linked to a higher risk of death in older adults after suffering a stroke, according to new research from the University of Aberdeen, published in Journal of the American Heart Association, the Open Access Journal of the American Heart Association/American Stroke Association.

Anemia is common in patients with acute stroke. Both anemia and low hemoglobin levels, which are proteins in red blood cells that carry oxygen throughout the body, are also common in older people,said Phyo Myint, senior study author and Professor of Medicine of Old Age at the University of Aberdeen in Scotland.

Researchers examined data from 8,013 hospital patients at an average age of 77 years old admitted with acute stroke between 2003 and 2015. They assessed the impact of anemia and hemoglobin levels on death at different time points up to one year following stroke.

Researchers 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 following either ischemic (clotted blood vessel) or hemorrhagic (ruptured blood vessel) stroke.

Additionally, elevated hemoglobin levels were associated with poorer outcomes and a higher risk of death, mainly within the first month following stroke, meaning both low and high levels of hemoglobin could be associated with a higher risk of death after stroke.

“We found that the likelihood of dying is about two times higher for ischemic stroke in people with anemia compared to those without it, and it’s about 1.5 times higher for a hemorrhagic stroke,” said Professor Myint. “So there’s the potential for a much poorer outcome if somebody comes in with stroke and they’re also anemic.”

In addition to the UK Regional Stroke Registry, researchers systematically reviewed the relevant literature published to date in this topic and used 20 previous studies to conduct a larger study by compiling data from a wide range of countries, increasing the study population to 29,943 stroke patients. This also increased the generalizability of the study findings and allowed to quantify the impact of anemia in a more robust way, researchers said.

Researchers believe the study emphasises the impact of anemia on stroke outcomes and the need for increased awareness and interventions for stroke patients with anemia.

“One such example of an intervention might be treating the underlying causes of anemia such as iron deficiency which is common in this age group,” said Raphae Barlas, co-author and medical student at the University of Aberdeen who carried out the project as a summer research scholarship program (ASRS) with the team. “As the study has convincingly demonstrated, anemia does worsen the outcome of stroke, so that is very important to ensure that we identify such at risk patients and optimize the management.”

Co-authors are Raphae Barlas MA; Katie Honney, MRCP; Yoon Loke, M.D.; Stephen McCall, BSc; Joao Bettencourt-Silva, Ph.D.; Allan B. Clark, Ph.D.; Kristian M. Bowles, Ph.D.; Anthony Metcalf, MBChB; Mamas A. Mamas, DPhil; and John Potter, D.M. Author disclosures are on the manuscript.

The Norfolk and Norwich University Hospital (NNUH) NHS Foundation Trust Stroke Services and NNUH Research and Development Department funded the study.