High-risk patients should be given antibiotics after receiving invasive dental treatment to reduce the risk of life-threatening heart infection, according to a study from the University of Sheffield.
The study, led by Professor Martin Thornhill from the University’s School of Clinical Dentistry, suggested that current UK guidelines recommending against the use of antibiotics are placing patients at unnecessary risk. Thornhill’s findings validate guidance from the USA, Europe, and elsewhere that recommends antibiotics are given to those at risk of heart infection.
“Infective endocarditis is a rare but devastating heart infection in which around 30% of people die within the first year of developing it. We know that 30-45% of IE cases are caused by bacteria that derive from the mouth, but what has been unclear and disputed until now is whether there is a strong link between invasive dental procedures, such as tooth extractions, and IE in patients who are at high risk of developing the infection,” explained Thornhill.
This is the largest study ever to examine the association between infective endocarditis (IE) – a life-threatening heart infection caused by bacteria in the mouth – and invasive dental procedures. The study was carried out in the USA where patients at high risk of heart infection (those with artificial or repaired heart valves or a history of IE) are provided with antibiotics before dental surgery. The results of the study found patients who received the prophylaxis antibiotic (AP) had a lower risk of heart infection.
Current guidelines could be leaving people at risk of heart infection
Guidelines recommending the use of AP for people at risk of heart infection have been in place since the 1950’s. However, until now, there has not been any robust research supporting the link between dental procedures and increased risk of heart infection.
“Results from our study validate for the first time the guidance of the major guideline committees around the world, such as The American Heart Association and the European Society for Cardiology, which recommend that those at high IE risk should receive AP before undergoing invasive dental procedures,” said Thornhill.
Due to the lack of previous research guideline committees have been reluctant to recommend AP amid concerns it could promote antibiotic-resistant bacteria. In most countries, AP only was recommended to be given to those at high risk of heart infection. In the UK, The National Institute for Health and Care Excellence (NICE) went further, stating: Antibiotic prophylaxis against infective endocarditis is not recommended routinely for people undergoing dental procedures.”
Analysing the data
The study analysed the medical records of nearly eight million people in the USA over a period of 16 months. Within this number, 36,773 of these individuals were at high risk of heart infection. The researchers examined whether patients who had invasive dental treatment went on to develop heart infections over the next 30 days and whether they had been given AP prior to the procedure.
They found that in 3,774 of those studied went on to develop IE within 30 days of their treatment. They also found that the risk of developing heart infection was 160 times greater in those at high IE-risk than in the general population.
The association between dental procedures and heart infection was particularly strong for tooth extractions and oral surgical procedures. For patients at high IE-risk, the risk of developing heart infection was one in every 250 extractions and one in every 100 oral surgery procedures without the use of AP.
However, the study found that only 32.6% of high IE-risk patients received AP before invasive dental procedures, allowing the researchers to study the effectiveness of AP. They found that the risk of developing heart infection was nearly 10 times higher when dental extractions were performed in high-risk patients without antibiotics, than with.
“It is reassuring for patients, cardiologists, and dentists that our data validates the American, European and other guidelines from around the world that recommend that patients at high risk for IE should receive AP before invasive dental procedures,” concluded Thornhill.