The study, published in JAMA Network Open, shows that higher levels of phosphorylated tau 217 (p-tau217)—a protein linked to the brain changes seen in Alzheimer’s disease—were strongly associated with future mild cognitive impairment and dementia among older women who were cognitively healthy at baseline, meaning at the start of the study before any memory or thinking problems were detected.

“Our study suggests we may be able to identify women at elevated risk for dementia decades before symptoms emerge,” said Aladdin H. Shadyab, Ph.D., MPH, first author of the study and UC San Diego associate professor of public health and medicine at the Herbert Wertheim School of Public Health and Human Longevity Science and the School of Medicine.