A robust proof-of-concept study has found it may be possible to predict a person’s risk of dying more than a decade in advance by analyzing their gut bacteria composition. The research points to a novel microbial signature that was associated with an increased risk of mortality across a 15-year follow-up period.
The new study, published in the journal Nature Communications, analyzed data from a large ongoing population-health survey in Finland called FINRISK. Fecal samples were analyzed from 7,211 adults, of an average age of 50. The samples were gathered in 2002 and the cohort’s health records were then tracked for the next 15 years.
"Finnish population studies are unique in their extent and scope even on a global scale,” explains Leo Lahti, corresponding author from the University of Turku. “With new data science methods, we are now able to study more closely the specific connections between microbiota and, for example, aging and incidence of common diseases.”
The research used a machine learning algorithm to detect microbial species in fecal samples that correlated with death over the long follow-up period. A strong link was identified between microbes in the Enterobacteriaceae family and increased mortality risk from gastrointestinal and respiratory causes.
Higher volumes of Enterobacteriaceae have been linked with colorectal cancer and inflammatory bowel disease, however, it is still unclear whether the relationship is causal. One study has found inflammation can promote the overgrowth of Enterobacteriaceae, so at this point it is not known whether this particular microbial signature simply offers an early sign of disease or whether it actively contributes to the development of disease.
"Many bacterial strains that are known to be harmful were among the enterobacteria predicting mortality, and our lifestyle choices can have an impact on their amount in the gut,” says Teemu Niiranen, another author on the new research. “By studying the composition of the gut microbiota, we could improve mortality prediction, even while taking into account other relevant risk factors, such as smoking and obesity. The data used in this research make it possible for the first time to study the long-term health impact of the human gut microbiota on a population level.”
The researchers are cautious to note they are nowhere near developing a microbiome test that can predict death. They state, “extensive research is still warranted” before the microbiome can be used to predict, prevent or treat any kind of human disease.
Nevertheless, this study is the first to link microbiome composition with long-term mortality outcomes and the findings offer researchers more clues to help direct future investigations into the relationship between our general health and the trillions of microbes living inside of us.
The new study was published in the journal Nature Communications.
Source: University of Turku