The universal blood donors with ‘O’ type blood are more protected from the risk of Alzheimer’s or memory loss compared to other blood groups, says a new study by the University of Sheffield. However, the famous case of Alzheimer’s that had caught the attention of the world was of former US President Ronald Reagan’s and incidentally, he was of ‘O’ blood group.
Of all the eight blood types in human body, A, B, AB and O with positive and negative equivalents, ‘O’ blood group is found to be protective for nervous system damage earlier than their counterparts with other blood types.
Alzheimer’s is the most common form of dementia, or memory loss and other cognitive functions as people age and about 60 to 80 percent of dementia cases are due to Alzheimer’s. Initially, it starts with mild memory loss, but with late-stage individuals lose the ability to carry on a conversation and respond to their environment.
Alzheimer’s is the 6th leading cause of death in the United States and mostly those found with later stage Alzheimer’s live for 10 to 20 years, depending on their healthcare conditions. Former US President and Hollywood fame Ronald Reagan, with ‘O’ blood group was one among those who died with Alzheimer’s disease, though the study claims that they are more protected from disease.
The new study was able to link now the blood types, which are crucial in determining the characteristics of some antigens, which fight foreign bodies including those from transfusion of other blood types necessitating a careful matching of the blood group.
The new study conducted by researchers at the University of Sheffield in collaboration with the IRCCS San Camillo Hospital Foundation in Venice has found for the first time the declining cognitive features in people with different blood groups, said Matteo De Marco and Prof. Annalena Venneri, from the University’s Department of Neuroscience, University of Sheffield. They have studied 189 Magnetic Resonance Imaging (MRI) scans from healthy volunteers of all blood groups to arrive at the revelations.
The MRI results showed that the volumes of grey matter are higher in O blood group than in others, with more grey matter in the posterior of the cerebellum in brain that helps them ward off from several brain diseases.
In their paper published in the Brain Research Bulletin, the researchers noted that the samller volume grey matter reflected more in other blood groups due to ageing, especially in temporal and limbic regions, including the left hippocampus that is the first to get affected with the onset of the Alzheimer’s disease.
Another finding is that the ‘O’ blood type people are “more protected against the diseases in which volumetric reduction is seen in temporal and mediotemporal regions of the brain like with Alzheimer’s disease for instance,” said Matteo DeMarco.
The researchers are, however, cautious to conclude saying more tests are required as the findings should be studied in association with other biological mechanisms. “What we know today is that a significant difference in volumes exists, and our findings confirm established clinical observations,” says Prof. Vennari. “We now have to understand how and why this occurs.”