Dr's Casebook: Gum disease can increase the risk of strokes and liver cancer

Dr Keith Souter writes: Researchers in Finland investigated the association between gum disease and risk of having a stroke. They did this by analysing thrombus aspirates, effectively, the clots of blood that block cerebral arteries to produce a stroke. Specialist neuro-interventional radiologists removed aspirates from 75 stroke patients as part of emergency treatment. They found that almost 80 per cent of them contained DNA from bacteria that came from the teeth and gums.

The research group has previously shown that the same oral bacteria are present in the coronary artery blockages of patients who have suddenly died. They have also found them in the thrombus aspirates of patients with lower limb thrombosis in both arteries and veins.

Another large study by researchers in Ireland analysed almost half a million people people in the UK, to examine the association between oral health conditions and the risk of a number of gastrointestinal cancers, including liver cancer. They found that poor oral health is associated with a 75 per cent increased risk of hepatobiliary cancer, the commonest type of liver cancer.

The reason why poor oral health may be strongly associated with liver cancer is uncertain. One explanation is because the liver contributes to the elimination of bacteria from the human body. When the liver is affected by diseases, such as hepatitis or cirrhosis, its function diminishes and bacteria will survive for longer. Another theory suggests that participants with a high number of missing teeth may alter their diet, consuming softer and potentially less nutritious foods, which in turn could increase the risk.

This is a very important finding, because it is believed that up to half of cases of liver cancer are preventable, with risk factors often relating to lifestyle, such as obesity, smoking and excess alcohol consumption. To that, now add the increased risk from gum disease. The research shows that oral health and good dental hygiene are of much greater importance to health than previously suspected. So, maintaining good oral health is so important.