Relationship between genetics and smoking

Smoking per se increases the risk of developing periodontitis. If this habit also coincides with an existing IL-1 polymorphism, the risk is magnified. It is all the more important to be aware of this.

A woman smoking a cigarette

Smoking is considered as one of the main risk factors for developing periodontal disease. The reduced blood flow to the tissue resulting from tobacco consumption and the associated reduction in immune competence can cause lasting damage to the periodontal apparatus. Smokers are therefore not only at increased risk of developing periodontitis. Periodontal treatments are also less effective in smokers than in non-smokers. According to studies, smoking is associated with a 2.9x increase in the risk of periodontitis.

Genetic factors increase the risk

The hereditary IL-1-mediated tendency to inflammation also has a major influence on the development and course of periodontitis. The increase in the risk of developing periodontitis is similar in a patient with variations in the IL-1 gene (2.7x) to that in a smoker (2.9x). If a genetic predisposition is compounded by the presence of additional risk factors, the effects of the latter are thus increased synergistically. If a patient who smokes also exhibits an IL-1 gene variation, this is associated with an approximately 8-fold increase in the risk of periodontal diseases.

What do these associations mean in practice?

It should be made very clear to the patient that the risk of periodontitis is greatly increased if he/she smokes despite IL-1 polymorphism. The patient should also be encouraged to maintain a particularly careful and regular oral hygiene routine. This is because, in such cases, even small quantities of bacteria may be sufficient to trigger severe inflammation. Existing evidence of IL-1 polymorphism can therefore help to motivate patients to give up nicotine and improve their oral hygiene habits. If the patient is unable to stop smoking, particularly careful monitoring is required, based on a regular recall schedule.