Periodontitis and diabetes: a two-way street

The reciprocal relationship

Based on the evidence, we can confidently say that the two diseases affect each other. In terms of how diabetes affects periodontal diseases, the key factor is how the hyperglycaemia is controlled and how the pathophysiology of the diabetes affects both the immune system and the tissues. There is evidence that periodontal tissues are affected and that these tissues have receptors for proteins or lipids known as advanced glycation end-products, that could make the periodontal tissues more susceptible to glycemia. This promotes inflammatory response in local tissues as we see increased susceptibility to periodontal inflammation and increased severity of the existing disease.

When we talk about how periodontal disease affect diabetes, the key factor is the systemic inflammation. Local inflammation disseminates to the systemic level, and then systemic circulation inflammation can make an individual more susceptible to developing diabetes or can diabetes management worse.

We cannot say that this is a causal relationship. It is more a question of the biological plausibility that the pathways interact with each other. Furthermore, there are some shared risk factors involved in both diseases, such as smoking and poor diet.

When we put all this together, we can confidently say that diabetes affects the periodontal tissues and periodontitis affects or can change the course of diabetes, especially when it comes to the complications of diabetes.

This reciprocal relationship is not just about the onset of diabetes or periodontitis, or about how one can affect the other. It also involves the response to treatment. There is evidence that someone who has diabetes—especially non-controlled diabetes—will not respond to periodontal treatment in the same way as someone who does not have diabetes.

For periodontists, there are several things to consider when we have a diabetic patient. Not just that they are more prone to develop periodontitis, but also that they are less likely to have a good response to periodontitis treatment. We can also say this the other way around: that being able to control periodontitis might lead to a better control of diabetes.

Can treating periodontitis well improve someone’s diabetes? The answer is probably yes. Ten years ago, it would not have been possible to say that. But we now have enough evidence in the literature to say that improving periodontitis can also improve diabetes control. In recent years, some studies have suggested a reduction of HbA1c levels of around 0.4% three or four months after periodontal treatment. This reduction of HbA1c levels has been compared to adding a second drug for controlling diabetes. This is a very powerful message.

It has been shown that a one-percent increase in HbA1c would cause a threefold increase in diabetic complications and vice versa—a one-percent decrease in HbA1c would significantly reduce the diabetic complications, especially all-cause mortality, cardiovascular disease, and other life-threatening diabetic complications.

Even a small change in HbA1c because of periodontal treatment would represent a big benefit to diabetes management.

Raising patient awareness of diabetes and pre-diabetes

As well as performing periodontal treatment, periodontists can also raise their patients’ awareness of diabetes and pre-diabetes. Periodontists and oral-health providers can be part of a team that increases the ability to control diabetes both by periodontal treatment and by encouraging improvements in lifestyle that help both periodontal disease and diabetes.

Informing the patient is very important because often they have never been told about the association between periodontal disease and diabetes, and often they do not have any symptoms suggestive of diabetes.

This connection needs to be explained to them and, if they have not been checked for diabetes, this moment would be a good opportunity. As dentists or dental professionals, we are often the first people who can start having that conversation.

Many studies have shown that a very large proportion of people (between 20% and 40% depending on the studies and settings) who present with periodontal disease have diabetes or pre-diabetes, and many of them were not aware of this, especially those who were pre-diabetic.

This is where there is an opportunity for us as dental professionals to help with detection and kickstart that process, which involves not only taking better care of their gums but also improving their lifestyle and eventually improving their overall health.

People often visit dental professionals more often than other medical professionals, so there is an opportunity to use this to identify potential diabetes patients and point them in the right direction. You could use very simple detection systems like the finger-prick test and then direct the patient to their family doctor depending on what you find.

How to educate patients

We need to listen to patients and understand how they receive this information and what is the most effective way of delivering it, so that they do not feel like you are telling them off or giving them a lecture, but rather that you are giving them helpful information they can use.

We are not experts in nutrition, but we can give them some ideas about the food they should or should not be eating, based on recent research. Even if the amount of information we can give is fairly limited, we can point them in the right direction and motivate them to lose weight and to have a healthy diet.

But this is not easy, particularly when there is so much easily available cheap junk food, while healthy food may be much more expensive.

Another element concerning diet is that people with advanced periodontitis have wobbly teeth and lose teeth. So, they often end up eating food that is less healthy because it is easier to chew and bite, rather than fresh vegetables that may be more difficult to chew.

Towards integrated healthcare

Integrated care is not just about dentists sending patients to the general practitioner but also in the other direction—if a doctor has someone with uncontrolled diabetes, they should ask for the patient to have a dental assessment because it is highly likely they will have a dental disease, particularly periodontitis.

The number of medical professionals who understand the importance of oral health is increasing, which is excellent. But there is still a lot of work to do.

The first step is to establish early-screening tools and protocols that might become a standard within the professions, and then implement them in the daily practice of dental and medical colleagues. The second step is to create interprofessional teams and integrated systems, so that when the dentist looks at a patient’s chart they can see when the patient last saw the endocrinologist, when they saw the dietician for counselling, and when they had had an eye exam. And, likewise, the medical person can see when they had a dental visit and when they received dental care.