Blood Test Gauges Age of 40+ Cell Types and Predicts Disease Risk

Overview

• A Stanford Medicine team published a Nature Medicine study reporting a blood-based method that estimates the biological age of more than 40 distinct cell types using proteomics and machine learning.
• The models were trained on more than 7,000 plasma proteins from 60,542 people across three cohorts and map circulating proteins to likely cellular origins to infer cell-level aging.
• Cellular-age signatures predicted future disease risk up to about a decade and were associated with mortality across roughly 15 years of follow-up in the cohorts studied.
• The study found strong, cell-specific links to disease risk, including extreme astrocyte aging sharply increasing Alzheimer’s risk in APOE4 carriers and aged skeletal muscle cells correlating with a 12.7-fold higher ALS risk.
• Investigators present the test as a tool to guide earlier, cell- or organ-targeted prevention and trial design, but they caution the findings are observational and require further validation before clinical use.