The Link Between the Oral Cavity and Stroke

Earlier this year I was honored to have the opportunity to speak to medical professionals at the University of Alabama at Birmingham (UAB) during their annual Stroke Symposium to discuss the link between the oral cavity and stroke. The correlation between oral health and systemic (full body) health is an area of ongoing research, with new correlations being found between the two as research continues to be published.

Brushing and flossing regularly have been proven to prevent gingivitis (reversible inflammation of the gums), which if left untreated, leads to periodontitis (inflammation/infection of the gums and supporting tissues of the teeth which can cause irreversible loss of bone and connective tissue). Many people have been told about these conditions by their dentist, but they may not know about the potential impact of gingivitis and periodontitis on their body or on other health conditions they may have.

How does gum disease affect the rest of the body? One key bit of information is that bacteria from your mouth has a potential pathway into your bloodstream through your gums. The part of your gums (the pink tissue around your teeth) that you can see is relatively tough because it contains keratin – a protein in our skin, nails, and many other tissues that provide protection from damage or stress. However, the part of the gums that we cannot see (that touches the teeth) is not keratinized, and therefore is much weaker, and can be more easily penetrated by bacteria. Not all bacteria are bad, but the ones that cause tooth decay and gum disease are. Bacteria entering your bloodstream, similar to high blood pressure and/or diabetes, can damage the lining of your blood vessels, which over time can contribute to heart attack or stroke.

After reviewing the currently available literature (published scientific research from reputable sources), I found several interesting points. Without getting too technical, I’ll try to go over the highlights of my findings.

– A 2011 study from the Journal of Oral Diseases found that patients with high blood pressure had a higher incidence of gum disease than patients without high blood pressure¹.

– A 2007 article reviewing many studies from the Journal of The Royal Institute of Public Health shows a link between diabetes and gum disease. Gum disease occurs more frequently in diabetic patients with elevated blood sugar levels than in non-diabetic patients. Also, there is evidence from numerous studies to support the concept that gum disease makes blood sugar more difficult to control. Diabetes is a known risk factor for stroke².

– A large 2012 meta-analysis (a study of other studies) from the Journal of Vascular Surgery found that people with gum disease were somewhere between 1.47 to 2.63 times more likely to have a stroke than people without gum disease³.

– A 2000 study from the Journal of Periodontology (gum and oral bone specialists) analyzed 50 plaques (the substance that clogs or blocks arteries) removed from the carotid artery (large artery in the neck). Almost half of these 50 plaques (44%) contained bacteria found in the mouth of people with gum disease⁴.

Currently, we cannot definitively say that gum disease causes stroke or cardiovascular disease. Correlation has been found between gum disease and stroke, not causation. And it may not be possible to outright prove causation. We cannot ask people to stop brushing and flossing and wait to see if they have a stroke – that would be dangerous and unethical. However, it is widely accepted that long-term (chronic) inflammation is not a good thing for the body. Infected gums are a potential source of chronic inflammation. It stands to reason that inflammation in the oral cavity may be a risk factor for stroke, and a healthier mouth can contribute to a healthier body.

In future posts I will share other links between the oral cavity and the rest of the body, as well as describe how we treat gum disease in our office.

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References:

1. Vidal F, Figueredo CM, Cordovil I, Fischer RG. Higher prevalence of periodontitis in patients with refractory arterial hypertension: a case-control study. Oral Dis. 2011 Sep;17(6):560–3. DOI:10.1111/j.1601-0825.2011.01800.x. Epub 2011 Feb 18. PubMed PMID 21332603.

2. Kuo LC, Polson AM, Kang T. Associations between periodontal diseases and systemic diseases: a review of the inter-relationships and interactions with diabetes, respiratory diseases, cardiovascular diseases and osteoporosis. Public Health. 2008 Apr;122(4):417-33. DOI: 10.1016/j.puhe.2007.07.004. Epub 2007 Oct 29. PubMed PMID 18028967.

3. Sfyroeras GS, Roussas N, Saleptsis VG, Argyriou C, Giannoukas AD. Association between Periodontal disease and stroke. J Vasc Surg. 2012 Apr;55(4):1178-84. DOI: 10.1016/j.jvs.2011.10.008. Epub 2012 Jan 14. PubMed PMID 22244863.

4. Haraszthy VI, Zambon JJ, Trevisan M, Zeid M, Genco RJ. Identification of Periodontal Pathogens in Atheromatous Plaques. J Periodontol. 2000 Oct;71(10):1554-60. DOI: 10.1902/jop.2000.71.10.1554. PubMed PMID 11063387.