A number of studies have suggested a possible association between periodontal disease and cardiovascular disease. There are two main reasons why they could be related; systemic inflammation increases when moderate/severe periodontitis is present, and treatment reduces this; bacteria involved with periodontal disease may invade damaged periodontal tissues and also the cardiovascular system potential causing damage.
The aim of this Cochrane review update was to investigate the effects of periodontal therapy for primary or secondary prevention of CVD in people with chronic periodontitis.
Methods
Searches were conducted in the Cochrane Oral Health’s Trials Register, CENTRAL, Medline, Embase, CINAH, OpenGrey, Chinese BioMedical Literature Database , China National Knowledge Infrastructure, VIP,US National Institutes of Health Trials Register , World Health Organization (WHO) Clinical Trials Registry Platform and Science paper Online databases.
Randomised controlled trials (RCTs) comparing the effects of different periodontal therapies for people diagnosed with chronic periodontitis, with or without cardiovascular disease (CVD), with follow-up times of at least one year. The studies could be primary prevention studies or secondary prevention studies. Two reviewers selected studies extracted data and assessed risk of bias using standard Cochrane methodology. GRADE criteria were used to assess the certainty of the evidence. The primary outcomes considered were all-cause and CVD-related death and all cardiovascular events (angina, myocardial infarction, stroke). Risk ratios (RR) and 95% confidence intervals (CI) were calculated for dichotomous data with Peto odds ratio (Peto OR) being used if the incidence of the events observed was very low. For continuous data, mean differences (MD) or standardised mean differences (SMD) and 95% CI were calculated.
Results
- 2 studies reported in 6 publications were included.
- Both studies were considered to be at high risk of bias.
- On study (165 patients) focused on primary prevention [very low certainty evidence].
- It was not possible to determine if scaling and root planning plus amoxicillin and metronidazole could reduce incidence of all-cause death, Peto OR = 7.48 (95%CI; 0.15 to 376.98), or all CVD-related death, Peto OR = 7.48 (95%CI; 0.15 to 376.98).
- The possibility that scaling and root planning plus amoxicillin and metronidazole could increase cardiovascular events compared with supragingival scaling may increase cardiovascular events measured at 12-month follow-up could not be excluded, Peto OR = 7.77 (95%CI; 1.07 to 56.1).
- One pilot study (303 patients) focused on secondary prevention. Patients received scaling and root planning plus oral hygiene instruction (periodontal treatment) or oral hygiene instruction plus a copy of radiographs and recommendation to follow-up with a dentist (community care). Only data on 37 participants was available at 1 years follow up so the data was not robust enough to be included. The study did not evaluate all-cause death and all CVD-related death.
Conclusions
The authors concluded: –
For primary prevention of cardiovascular disease (CVD) in people diagnosed with periodontitis and metabolic syndrome, very low-certainty evidence was inconclusive about the effects of scaling and root planning plus antibiotics compared to supragingival scaling. There is no reliable evidence available regarding secondary prevention of CVD in people diagnosed with chronic periodontitis and CVD. Further trials are needed to reach conclusions about whether treatment for periodontal disease can help prevent occurrence or recurrence of CVD.
Comments
This review presents an update of the 2017 Cochrane review (Dental Elf – 10th Nov 2017) retaining the term ‘chronic’ periodontitis (pocketing ≥ 4 mm) and not adopting the new classification for periodontal diseases which will be introduced with the next update of this review.
This update includes one additional study which focuses on primary prevention of CVD. Unfortunately, both included studies are considered to be at high risk of bias and provide only very-low certainty evidence. As the authors indicate this leaves very limited evidence for assessing the impact of periodontal disease on the prevention of cardiovascular disease. The review authors highlight the need for further RCTs highlighting a number of issues that should be considered in the design of future studies. One of the main reasons for study exclusions was because the follow-up periods were shorter than 12 months so clearly longer-term follow elements will be one of the many issues that needs to be addressed with future studies.
Links
Primary Paper
Liu W, Cao Y, Dong L, Zhu Y, Wu Y, Lv Z, Iheozor-Ejiofor Z, Li C.
Periodontal therapy for primary or secondary prevention of cardiovascular disease in people with periodontitis. Cochrane Database of Systematic Reviews 2019, Issue 12. Art. No.: CD009197. DOI: 10.1002/14651858.CD009197.pub4
Other references
Cochrane Oral Health Group Blog – Treating chronic gum disease to prevent heart disease
Dental Elf – 10th Nov 2017
Treating periodontitis to prevent heart disease – evidence unclear
