Results showed that the 2,714 individuals who tested positive had a higher risk for death from CRC (HR 7.79, 95% CI 6.13-9.89, P < 0.0001) and from all non-CRC causes (HR 1.58, 95% CI 1.45-1.73, P < 0.0001), than those who tested negative.
“What we found that is that if you had a positive test, you were more likely to die from colorectal cancer, which is what we expected, but we also found that all-cause mortality was higher,” Dr. Steele said. “We then linked this data with specific causes of death and found that the risk of dying from a series of other diseases such as heart attacks, circulation disorders, respiratory disease, and many other cancers was also higher.”
Why would fecal occult blood be associated with, say, a heart attack? It’s not clear why or how just yet, Dr. Steele said. “But we think that it might be related to levels of inflammation throughout the body as this is a marker of general ill health, and chronic inflammation is a driving factor behind whole series of whole host of other diseases,” he said. “In any event, if someone is found to have unexplained blood in their feces, it may mean that they are at risk of developing chronic disease and may benefit from attention to their lifestyle.”
The next step in this line of research will be prospective studies to find a link between lifestyle diseases and fecal bleeding. “If hemoglobin in feces is a risk factor for all-cause death, it may have potential as a modifiable biomarker that could be used to assess the efficacy of both lifestyle and drug interventions to reduce the risk of premature mortality,” Dr. Steele and coauthors predicted.
This study was funded by the Chief Scientist Office of the Scottish Government Health Department.