Your stool can reveal your risk of cardiovascular disease

A new study from Monash University has linked the presence of certain faecal proteins to deadly cardiovascular conditions like heart failure, finding they can be used as an early indicator of risk and outcomes. This is a breakthrough in the early prevention and diagnosis of conditions that could otherwise go hidden until they become fatal, as revealed in the journal Gut Microbes.

“Unless you have gastrointestinal diseases, you might never have tests that allow us to determine what is happening inside the human gut, as these are expensive and invasive,” said Monash Professor Francine Marques.

“But if it were as simple as collecting a sample when you go to the toilet, more people would be in a position to find out their risk factors earlier and be in a position to take preventative steps.”

Researchers used a method known as metaproteomics to look at the proteins contained in the faecal samples. They studied samples from 63 people from Melbourne and Shepparton who were not known to suffer from gastrointestinal or cardiovascular diseases and 27 samples from patients with heart failure.

“We often sequence DNA to identify microbial genetic make-up, but this is the first time we have studied the proteins in faecal samples instead,” Marques said.

Using this method, the team identified both human and microbial proteins. These proteins were compared with over 34,000 samples from healthy people who were followed up over a period of 15–20 years, with the team ultimately finding that they could be used to predict the long-term risk of having a heart attack or a stroke.

“Finding out our risk early means we can address the causes, like diet or lifestyle, and give ourselves the best chance of healthy aging,” Marques said.

The news comes some months after a separate, Monash-led study found a surprising connection between constipation and an increased risk of major adverse cardiac events (MACE) — including heart attacks, strokes and heart failure — with their results published in the American Journal of Physiology-Heart and Circulatory Physiology.

The research team analysed data from 408,354 participants in the UK Biobank, identifying 23,814 cases of constipation. Their findings showed that individuals suffering from constipation were more than twice as likely to suffer from a major cardiac event as those without constipation.

Moreover, the study highlighted a particularly concerning link between constipation and hypertension. Hypertensive individuals who also suffered from constipation were found to have a 34% increased risk of subsequent cardiac events compared to those with hypertension alone.

“Our research suggests that constipation may exacerbate the cardiovascular risks associated with high blood pressure, further increasing the likelihood of heart attacks and strokes,” said Marques, who led the study.

The research also explored the genetic links between constipation and cardiovascular disease. According to Monash’s Dr Leticia Camargo Tavares, co-first author of the study, “Positive genetic correlations were identified between constipation and various forms of MACE, indicating that shared genetic factors may underlie both conditions.”

With constipation affecting an estimated 14% of people, Marques says a significant portion of the population may be at an increased risk of cardiovascular disease due to their bowel health. Further research will be needed to explore the causal relationship between constipation and MACE and to identify the specific biological pathways involved.

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