Heart disease sufferers at twice the risk of bowel cancer, study warns

At risk: drugs should be developed to prevent both heart disease and bowel cancer, say campaigners

And those who smoke or have a condition linked to diabetes are even more likely to end up with a bowel tumour.

Scientists looked at the prevalence of bowel cancer or pre-cancerous tumours in patients who had recently been diagnosed with coronary artery disease.

They found 34 per cent of patients with the artery problem had neoplasms in their bowel, a sign of cancer risk, and 18.4 per cent had advanced cancerous lesions, against 18.8 per cent and 8.7 per cent in those without heart problems.

The prevalence of actual cancer was 4.4 per cent among those with artery disease against 0.5 per cent in those without.

Half of the cancers found in the first group were at the early stages.

Coronary artery disease, a narrowing of arteries due to deposits of fat and cholesterol, kills more than 100,000 Britons a year and is the most common cause of death.

Bowel cancer, which is often linked to a poor diet, claims 16,000 lives a year.

The Hong Kong study, published in the Journal of the American Medical Association, found that those who smoked were even more likely to have advanced, cancerous lesions.

And those with metabolic syndrome, which causes the body to resist insulin and can lead on to diabetes, also have an increased risk.

Scientists believe the link might be that both heart disease and bowel cancer are associated with the inflammation of the gut by bacteria.

The authors said: "Inflammation is now recognised as being pivotal in coronary artery disease.

"Colo-rectal cancer is also thought to progress through the pathway of inflammation."

A spokesman for the British Heart Foundation said: "This study identifies an association between colorectal cancer and coronary heart disease, which is not the same as saying one causes another.

"It is possible that both conditions develop through the mechanism of chronic inflammation - which may account for this association.

"But the association could also be due to shared lifestyle risk factors such as smoking, physical inactivity and poor diet."

Rob Glynne-Jones, of Bowel Cancer UK, said: "This is an intriguing study which could have a lot of implications.

"If inflammation caused by a bacteria is the link between the two, it means that drugs could be developed to try to prevent both heart disease and bowel cancer.

"Prevention is a much nicer strategy than cure."