Periodontal disease and coronary disease risk

Both coronary heart disease and periodontal disease are common and for many decades reviews have suggested that there was an association between the two. In 2012 the American Heart Association stated that the currently available evidence was insufficient to establish a cause-and-effect relationship between periodontal disease and heart disease. The aim of this review was to evaluate the association between periodontal disease (PD) and coronary heart disease (CHD)

Methods

The databases PubMed, Web of Science and Embase were searched for prospective cohort studies investigating the association between periodontal disease and CHD. The outcome of interest was CHD-related morbidity (fatal and nonfatal) or mortality, evaluated using the relative risk (RR) or hazard ratio (HR) and their corresponding 95% confidence intervals (CIs) by a fixed-effect meta-analytical model.

Results

15 studies involving at total of 230,406 patients were included
Periodontal disease was associated with a significantly increased risk of developing CHD : RR=1.19; (95% CI; 1.13–1.26; P = 0.001).
Sensitivity analysis showed that exclusion of any individual studies did not change the results

Subgroup analysis	No. of studies	Risk Ratio (95% CI)
Adjustment for confounding factors – Weak	8	1.20 (1.11–1.29)
Adjustment for confounding factors – Strong	7	1.18 (1.08–1.29)
Assessment of Periodontal disease – dental exam	9	1.20 (1.12–1.28)
Assessment of Periodontal disease – self assessment	6	1.24 (1.04–1.49)

Cumulative analysis by the order of publication year demonstrated a stable, statistically significant

Conclusions

The authors concluded:

Our findings indicated that PD was significantly and independently associated with an increased risk of CHD. This meta- analysis of prospective cohort studies included the latest available evidence and provided up-to-date insights into the relationship of periodontal health and the risk of developing CHD. Subgroup analyses showed similar results between male and female participants. Further epidemiological studies are warranted to further establish and confirm this association, which would have significant implications on current clinical practice as to whether patients with periodontal disease should have frequent dental check-up with an emphasis on CHD assessment.

Comments

This review has searched 3 major databases for studies and focused on prospective cohort studies to assess the association between periodontal disease and CHD. The published paper lacks important detail on the methodology although as the protocol was published in PROSPERO some additional information is available. For example, two authors extracted data and study quality was assessed using the Newcastle-Ottawa Scale although it is not clear if this was done independently and the quality assessment of the individual papers is not presented.

One of the challenges with periodontal disease studies is variation the definitions and reporting of the condition and 5 of the included studies used self-reporting of periodontal disease although interestingly the subgroup analysis did show a major impact on the risk ratio. All of the included studies adjusted for 3 or more confounders with some including as many as 10. The authors dichotomised the studies into those with strong and weak adjustment based on the whether they were higher or lower than the median number of confounders.