The Link Between Hemoglobin and Dementia

The level of hemoglobin in most healthy people is stable. Hemoglobin plays a vital role in the transport of oxygen in the body. If the level of hemoglobin was to drop, the person would have difficulty providing the tissues with oxygen. In some cases, the hemoglobin levels may be too high, and that could be due to blood transfusions, certain medical disorders and use of the hormone, erythropoietin. 

Low levels of hemoglobin indicate anemia which could be due to acute blood loss, failure of the bone marrow to make red blood cells, exposure to radiation, the toxicity of certain drugs and disorders like sickle cell anemia and thalassemia. Anemia or low hemoglobin is a very common clinical problem seen in patients of all ages and affects nearly 1.6 billion individuals worldwide.

Over the years, it has been established that low levels of hemoglobin are associated with poor health outcomes, including the development of heart attacks and strokes. But there is very little data on how hemoglobin levels may impact dementia. One early study showed that low levels of hemoglobin were linked to dementia, but the study was criticized as it only followed the participants for 3 years. 

But a new study that was conducted recently shows that people who have lower than normal or higher than normal levels of hemoglobin may have a high risk of developing dementia with advanced age. Researchers from Erasmus Medical Center in Rotterdam, the Netherlands conducted a study to determine if there was a link between levels of hemoglobin, dementia, and anemia. The results of the study are published in the journal Neurology.

These researchers obtained data from 12,300 participants with an average age of 65. None of the participants had been diagnosed with dementia at the start of the study. The hemoglobin levels of the patients were checked before the study, and only 6.1% or 745 participants had anemia. They followed the patients for 12 years and noted that 1,520 individuals developed dementia. In addition, the researchers also looked at brain imaging studies of 5,319 participants which allowed them to determine the cause of dementia (e.g., stroke, bleeding). The researchers also took into account many other variables like smoking, gender, alcohol consumption, kidney function, diabetes, obesity and cholesterol levels.

What they noted was that participants with either low or high levels of hemoglobin had a higher risk of dementia compared to participants with normal levels of hemoglobin. Participants with dementia also had a greater number of changes in the white matter and other areas of the brain related to dementia. Also, it was noted that people with low hemoglobin were more likely to have at least one small bleed in the brain compared to participants with no anemia.

Unfortunately, this study cannot prove that the hemoglobin levels cause anemia because they also noted changes in the blood vessels in the brain. However, more evidence is accumulating which indicates that low levels of hemoglobin are associated with less oxygen delivery to the brain, which may lead to tissue damage.

Categories:
Blog Popular
Tags