One in three women and one in seven men will develop dementia at some point in their lives. There is no cure yet so our best bet is to avoid as many risk factors as possible. Researchers from Oxford have listed no fewer than 161 and concluded that three are clearly the most harmful.
The learned British looked at the brain scans of 40,000 people aged 45 and older. They obtained that data because they had access to the UK Biobank. This is an extremely large and long-term health study in the United Kingdom for which at least half a million Britons have been followed for years. It is also an important source for cancer research, for example.
Air pollution, alcohol and diabetes
The Oxford scientists clustered the 161 risk factors into fifteen categories: blood pressure, cholesterol, diabetes, weight, alcohol consumption, smoking, depression, inflammation, pollution, hearing loss, sleep, social contact, diet, exercise and education level. Three factors stood out: diabetes, traffic-related air pollution and alcohol consumption.
Weak spot in your brain
To reach this conclusion, we zoomed in on a weak spot in the brain: a specific network of brain areas that is focused on so-called higher order thinking, such as analyzing, being creative and evaluating. This brain area only develops at the end of puberty and ages faster than the rest of your brain. The network is also particularly sensitive to schizophrenia and Alzheimer’s. In the new study, which in Nature appeared, the scientists investigated the genetic and adaptive influences on this fragile brain region by looking at the aforementioned brain scans.
“We know that a constellation of brain areas are more likely to deteriorate with age and in this study we have shown that these specific areas of the brain are most vulnerable to diabetes, traffic-related air pollution – a growing and major factor in dementia – and alcohol,” said lead researcher Professor Gwenaëlle Douaud.
Elusive antigen
“We have discovered that several variations in the genome affect this brain network and they are associated with cardiovascular disease, schizophrenia, Alzheimer’s and Parkinson’s, but also with the two antigens of a little-known blood group, the elusive XG antigen system, which was a completely new and unexpected finding.”
That deserves some explanation. This comes from co-researcher Professor Lloyd Elliott: “In fact, two of the seven genetic findings are in this specific area that contains the genes of the XG blood group, a very atypical part of the brain because it is shared by both X and Y chromosomes . This is very intriguing, because we don’t know much about these parts of the genome yet. Our work shows that there is benefit in further discovering this genetic terra incognita.”
Antigens
Blood group antigens are proteins on the outside of red blood cells. These antigens determine which blood group you have. The XG antigen is relatively unknown. It was only discovered in 1962 and is located on the short arm of the X chromosome
But in practice this is not of much use for the time being. We can do something with the risk factors that have been identified as the most dangerous. “What makes this study special is that we studied the unique contribution of each risk factor by looking at them all together. This allowed us to measure the resulting deterioration of the specific weak spot in the brain. This comprehensive, holistic approach, in which we have also corrected for age and gender, has identified three risk factors that are the most harmful: diabetes, air pollution and alcohol,” it reiterates.
So you can take action yourself to reduce your risk of dementia. There is not much you can do about air pollution in a densely populated country like the Netherlands. But what you can do is ensure that you do not develop diabetes by maintaining a healthy weight. You can also cut down on alcohol. Just maybe you can outsmart that nasty disease.
