Published 11.14
Blood tests can reveal signs of Alzheimer’s years before the disease starts, according to new findings.
– In the future, if we have effective treatments available, this could become extremely important, says Henrik Zetterberg at the University of Gothenburg.
It is American researchers who are behind the new study, which was published in the journal Lancet. They have seen that levels of, among other things, the protein phosphorylated tau, which is linked to Alzheimer’s disease, can increase already in the 60s.
In the study, the blood of 1,350 people without dementia and with an average age of 61 was examined. They also had to perform different types of cognitive tests.
Worse on tests
86 of the participants had elevated levels. These also performed worse on average on tests that show the ability to plan, focus and take on new tasks. The tests were repeated every five years and those who had elevated levels on the first occasion deteriorated faster than others.
Blood samples to identify the protein tau are already used today in some regions as part of the diagnosis of Alzheimer’s disease.
– It is a simpler way than the spinal fluid tests and brain imaging that are used today, says Henrik Zetterberg, chief physician at Sahlgrenska University Hospital and professor of neurochemistry at the University of Gothenburg.
He has been involved in developing the blood test used in Sweden.
– We have seen that in 70-year-olds, around 10 percent have an increase in these markers. Here you can see that the process probably starts earlier, he says.
No treatment available
Today, there are no approved medicines available in Sweden that target the changes that tau and another protein, betaamyloid, can cause in the brain. But development is ongoing at several pharmaceutical companies. Henrik Zetterberg believes that when more effective drugs with fewer side effects come along, early tests can be beneficial.
– Most treatments will do the most good if they are started early. But at the moment there is no reason to test widely because it risks leading to unnecessary concern, he says.
Last spring, the expert body NT Council came up with the recommendation that the healthcare system should not use the approved drug Leqembi. The council is also investigating whether another drug, Kinsunla, should be recommended or not.
Henrik Zetterberg has previously held lectures sponsored by companies that market the two drugs.
Alzheimer’s disease
Alzheimer’s is the most common dementia. In Sweden, roughly 100,000 people are affected.
A characteristic of the disease is that the brain tissue is gradually destroyed.
The most important risk factors are old age and heredity. Lifestyle also affects.
The probability of being affected increases significantly after the age of 65.
According to studies, around 40 percent of disease cases can be traced to lifestyle factors. These include high blood pressure, diabetes and other metabolic diseases, as well as physical inactivity.
Source: Alzheimer’s Foundation, Dementia Centre
