The groundbreaking early diagnosis that may revolutionize dementia treatment: A new study reveals that a simple blood test may identify women at risk of developing dementia – up to 25 years before the first symptoms appear. The researchers found a strong link between high levels of a certain protein in the blood and the future onset of cognitive decline and dementia. The findings raise hope that in the future it will be possible to enable early prevention or delay of the disease, but at this stage it is only a research tool.
The study was conducted by researchers from the University of California, San Diego and was published in the medical journal JAMA Network Open. The researchers examined blood samples collected in the late 1990s as part of a large-scale study called Women’s Health Initiative Memory Study. The study included 2,766 women aged 65 to 79 who did not suffer from cognitive decline at the beginning of the follow-up.
The researchers followed the participants for about 25 years, and examined whether the blood tests performed at the beginning of the study could predict which of them would later develop mild cognitive impairment or dementia. The central finding was a strong link between high levels of a protein called phosphorylated tau 217, or in short p-tau217, and the future risk of developing dementia.
The tau protein is one of the main components involved in the development of Alzheimer’s disease and other neurodegenerative diseases of the brain. Under normal conditions, the protein helps stabilize structures within nerve cells. When chemical changes occur in the protein, especially a process of phosphorylation, it may accumulate in the brain and create pathological structures that impair cell function.
The study found that women whose p-tau217 levels in their blood were higher at the beginning of the follow-up were at a much higher risk of developing cognitive decline or dementia later in life. The researchers found that the test was able to identify the risk many years before the first signs of the disease appeared.
The possible significance of this finding is that a relatively simple blood test may in the future serve as a tool for early identification of people at risk of the disease. Today, the diagnosis of Alzheimer’s and other dementias is based mainly on clinical symptoms, brain imaging tests, or tests of cerebrospinal fluid. These tests are more complex and sometimes invasive.
Blood tests based on biological markers are considered one of the most promising developments in dementia research. They may be more accessible and cheaper and allow large-scale screening in the population. The researchers note that such tests may also be used in the future to evaluate the effectiveness of new treatments designed to slow the progression of the disease.
The study found that the relationship between the protein and the risk of dementia was not identical across all groups of women. Women aged 70 or older who had high levels of the protein in their blood experienced worse cognitive outcomes compared to younger women. Women who carried the APOE ε4 gene, which is considered a known risk factor for Alzheimer’s disease, were also found to be at higher risk when the protein levels in their blood were high.
Another finding in the study showed that the protein was a particularly strong predictor of dementia among women who received hormone therapy that included estrogen and progestin, compared to women who received a placebo. The researchers note that further studies are needed to understand how different factors such as genetics, hormone therapy, and age-related chronic diseases affect the relationship between the biological marker and the development of dementia.
Despite the encouraging findings, the researchers emphasize that the test is not intended at this stage for routine clinical use. Blood tests for Alzheimer’s and dementia are still in the research stages, and there is currently no recommendation to perform them routinely in people without symptoms. The researchers also note that this is a study that examined older women only, and therefore it is still unclear whether the findings are also valid for men or for younger people. In addition, the study examined dementia in general and did not focus only on Alzheimer’s disease.
However, experts in the field estimate that the ability to identify biological changes associated with dementia decades before symptoms appear may in the future change the way medicine deals with the disease. Early detection may allow earlier interventions, closer medical monitoring, and perhaps also treatments that will succeed in delaying the progression of the disease.
Dementia is a general name for a group of neurodegenerative diseases of the brain that cause progressive impairment in memory, thinking, and the ability to perform daily activities. Alzheimer’s disease is the most common cause of dementia and accounts for about 60% to 70% of cases. In the early stages, memory difficulties, confusion, and disorientation in time and place usually appear. Later, language impairment, difficulty making decisions, and changes in behavior and personality may develop. The disease progresses gradually over years, and in its advanced stages patients require full assistance with basic activities such as eating, dressing, and mobility. There is currently no cure for the disease, but there are drug and rehabilitative treatments that can to some extent slow the progression of symptoms.