Blood Test May Forecast Dementia Risk in Women Decades in Advance
A groundbreaking study published in the Journal of the American Medical Association on Wednesday suggests that a simple blood test could predict the risk of dementia in women as early as 25 years before symptoms emerge. Researchers investigated the link between levels of the protein plasma phosphorylated tau 217 (p-tau217) in the blood and the likelihood of developing mild cognitive impairment (MCI) or dementia. P-tau217 is recognized as a biomarker for Alzheimer's disease, making this finding particularly significant for early detection strategies.
Study Details and Key Findings
The research involved a cohort of 2,766 women in the United States, aged 65 to 79, who showed no signs of cognitive impairment at the study's outset. Participants were recruited between 1996 and 1999 and were monitored for up to 25 years, through 2021. By the conclusion of the study, 1,311 women had developed either MCI or dementia. The analysis revealed that those with higher baseline levels of p-tau217 at the beginning were more likely to progress to these conditions.
Aladdin H. Shadyab, an associate professor of public health and medicine at the University of California, San Diego and lead author of the study, emphasized the implications. "The key takeaway is that our study suggests it may be possible to detect risk of dementia two decades in advance using a simple blood test in older women," he told Fox News Digital. "Our findings show that the blood biomarker p-tau217 could help identify individuals at higher risk for dementia long before symptoms begin."
Hormone Therapy and Demographic Factors
The study also explored other associations by randomizing participants into groups: one received estrogen hormone therapy versus a placebo, and another received estrogen plus progestin hormone therapy versus a placebo. Researchers found that the link between p-tau217 and dementia was stronger in women assigned to estrogen plus progestin therapy compared to those on a placebo. However, this association did not vary significantly in the estrogen-only versus placebo group.
Additionally, larger associations between p-tau217 and dementia or MCI were observed in women older than 70 and those carrying the APOE ε4 gene, which is known to increase Alzheimer's disease risk, according to the Cleveland Clinic.
Limitations and Subgroup Variations
Despite its promising results, the study had notable limitations. It focused exclusively on older women and did not examine dementia by subtype. Moreover, the sample size of Black women was smaller than that of white women, potentially affecting outcomes. The research indicated that p-tau217 associations with MCI or dementia were greater in white women than in Black women, and p-tau217 was not linked to incident MCI in Black women. However, similarities were found between racial groups in predicting dementia based on age and p-tau217 levels.
Ian McDonough, an associate professor at the State University of New York at Binghamton who was not involved in the study, commented to Medical News Today that "plasma biomarkers are not going to be a one-size-fits-all forecasting solution." He stressed the need to identify subgroups, such as older and middle-aged adults, for whom these markers might be most predictive, noting that in some cases, like for Black Americans, they could be misleading by suggesting low risk when actual risk is high.
Early Signs and Preventive Measures
While this study highlights a potential tool for early risk assessment, other research underscores the importance of lifestyle factors in reducing dementia risk. Physical and mental activities, along with a healthy diet, can play crucial roles in prevention. Being aware of early signs is also vital.
Dr. Stephanie Nothelle, a geriatrician and associate professor at the Johns Hopkins School of Medicine in Baltimore, previously told HuffPost that early dementia signs can vary but often include:
- Short-term memory loss
- Personality changes
- Consistent difficulty with word-finding
- Trouble with planning complex tasks
She explained that "executive functioning" involves the planning part of the brain, such as organizing a dinner party. "If you're not able to do that anymore, that can be a sign that there's something going on," Nothelle said. Overall, individuals should consult healthcare providers with any concerns about cognitive health.
