A routine blood test that most patients undergo during regular check-ups may hold significantly more health information than previously utilized, according to groundbreaking research published in Nature. Scientists have discovered that the complete blood count (CBC) could serve as a powerful tool for early disease detection and risk assessment across multiple conditions.
Researchers from Massachusetts General Hospital analyzed blood samples from more than 25,000 patients and determined that each individual has unique "set points" for various blood components measured in a CBC. These personalized baselines could help physicians identify early-stage diseases in otherwise seemingly healthy individuals.
"Complete blood counts are common tests, and our study suggests CBCs vary a lot from person to person even when completely healthy, and a more personalized and precision medicine approach could give more insight into a person's health or disease," explained Dr. John Higgins, a pathologist at Massachusetts General Hospital and senior researcher on the study.
Disease Indicators in Blood Components
The study identified several specific correlations between blood components and disease risks:
- Lower hemoglobin concentration was associated with increased risk of heart attack, stroke, and heart failure
- Elevated white blood cell counts correlated with higher type 2 diabetes risk
- Red blood cell size variations could help assess osteoporosis and irregular heart rhythm risk
- The percentage of red blood cells in blood showed potential for detecting kidney disease
Perhaps most striking was the finding that extremely high or low blood count set points in apparently healthy individuals were associated with an absolute 10-year mortality risk that varied by more than 5%.
"Set points seem to identify large fractions—more than 20%—of healthy adults in our study population with more than 2% to 5% increase in absolute 10-year risk of all-cause mortality or diagnosis of major diseases, including cardiovascular disease and diabetes and other conditions for which early intervention can be effective," the researchers wrote.
Alcohol Consumption Biomarker Shows Promise
In a parallel development, researchers from the University of California, San Francisco have identified another blood biomarker that could transform how physicians assess alcohol consumption and related liver damage.
Their study, published in the American Journal of Gastroenterology, found that a blood-borne byproduct of alcohol metabolism called phosphatidylethanol (PEth) accurately reflects alcohol consumption levels and correlates strongly with liver damage.
"This is a more direct way to measure the harm that alcohol is causing in the body than asking patients," said Judy Hahn, a professor in UCSF's Division of HIV, Infectious Diseases and Global Medicine. "We don't ask someone how much fatty food they eat. We measure their cholesterol. We don't ask people how much they think they weigh. We weigh them."
The UCSF team pooled data from 12 previous studies conducted across the United States, Russia, Uganda, and South Africa, involving more than 4,600 adults. Their analysis revealed that elevated PEth levels tracked closely with liver disease scores, while self-reported drinking habits did not show strong correlation with actual liver damage.
Clinical Implications and Future Directions
These findings suggest that blood testing could be refined to provide more comprehensive health assessments during routine check-ups. For the CBC analysis, researchers noted that the approach produces "a 2- to 4-fold relative risk stratification, which is comparable to that provided by common disease screening factors including family history and some genetic mutations."
The PEth testing could be particularly valuable given the prevalence of alcohol misuse in the United States. According to CDC data, about 24% of U.S. adults binge drink, and more than 6% are heavy drinkers—numbers that increased during the pandemic.
"To prevent and manage liver fibrosis, we need to know how much a person is drinking," said Pamela Murnane, an assistant professor of epidemiology and biostatistics with UCSF. "We clearly don't have a good grasp on that with self-report."
Both research teams suggest that incorporating these advanced blood analyses into standard medical practice could significantly improve early disease detection and intervention. For conditions like liver scarring, which can be slowed or even reversed through lifestyle modifications, early identification is critical.
While further research is needed to fully understand the mechanisms behind these associations, the studies represent significant steps toward more personalized and precise medical assessments using readily available blood testing technology.
