Researchers led by the University of Sheffield are urging the National Institute for Health and Care Excellence (NICE) to review dental antibiotic prophylaxis guidelines to protect those at high risk of developing a serious heart infection.

The research found that dental patients at high risk of infective endocarditis, a life-threatening infection of the heart valves that causes heart failure and strokes, should be given antibiotics before undergoing invasive treatment such as extractions or oral surgery. The University of Sheffield says the study provides evidence that current UK guidelines could be putting high-risk patients at unnecessary extra risk when undergoing invasive dental procedures.

Infective endocarditis (IE) is a serious heart infection which can be fatal. Thirty per cent of people will die within one year of diagnosis. In around 30-40 per cent of cases it is caused by bacteria that come from the mouth either from poor oral hygiene or during invasive dental procedures.

To prevent this, patients at increased risk of IE - those who have undergone cardiac interventions such as prosthetic heart valves, valve repairs and congenital heart disease repairs - were recommended to have antibiotic prophylaxis (AP) cover before undergoing invasive dental treatment.

However, in 2008, NICE recommended against the use of antibiotic prophylaxis (AP) because there was a lack of evidence for efficacy and concerns about the possibility of adverse reactions to the antibiotics used.

Although guideline committees around the world had similar concerns, they continued to recommend AP for those patients at highest risk of developing IE because they felt the risks of developing IE far outweighed any risks of giving AP to this group of patients.

Despite considerable new evidence that AP is safe, effective and would result in significant cost savings and health benefits, NICE has not reviewed their recommendation against the use of AP since 2015.

A study led by the University of Sheffield’s School of Clinical Dentistry in collaboration with Bernard Prendergast, a consultant cardiologist at St Thomas’ Hospital and Cleveland Clinic London UK, Mark Dayer, a professor and consultant cardiologist at the Cardiovascular Research Institute in Ireland, Ash Frisby, an endocarditis patient advocate, and Larry Baddour, a professor of medicine at the Mayo Clinic College of Medicine, and published in The Lancet Regional Health found:

  • The risk of IE in high-risk patients following invasive dental procedures as a whole is one in 1,000 - this falls to one in 3,333 if AP is given before the procedure.
  • The risk of IE in high-risk patients following extractions is one in 100 - this falls to one in 1,000 if AP is used.
  • The risk of IE following oral surgery is one in 40 - this falls to one in 500 if AP is used.

In contrast, the risk of a significant adverse drug reaction following amoxicillin AP is only one in 250,000 prescriptions, and none of these would be fatal while three in 10 people with IE would die within one year.

Martin Thornhill, from the University of Sheffield’s School of Clinical Dentistry and lead author of the study, said, “Infective endocarditis is a rare but devastating heart infection in which around 30 per cent of people die within the first year of developing it.

“All major guidelines committees around the world, such as The American Heart Association and the European Society for Cardiology, recommend that those at high-risk of infective endocarditis should receive antibiotic prophylaxis before undergoing invasive dental procedures. We are urging NICE to review its guidance so that high-risk patients in the UK receive the same protection against IE that is afforded to patients in the rest of the world.

“There are currently 400,000 people at high-risk of developing IE in the UK and this number is increasing each year due to the growing number of patients having cardiac interventions.

“Our previous study showed that prescribing antibiotic prophylaxis would be cost-effective if it prevented just 1.4 high-risk patients per year from developing infective endocarditis. So, by preventing between 40 and 260 cases per year antibiotic prophylaxis would be highly cost effective and would likely save the NHS in excess of £5.5m annually as well as generating substantial health gains for those at risk of endocarditis.”

Author: