Meta-analysis of periodontal disease and risk of coronary heart disease and stroke

Objective. The purpose of this study was to analyze published studies and abstracts in order to provide a quantitative summary of periodontal disease as a risk factor for cardiovascular disease and to explore the possible causes for conflicting results in the literature. Study design. We searched all published literature on the Medline literature search engine since 1980. An additional search was performed with bibliographic citations from each article. Nine cohort studies (8 prospective and I retrospective), in which relative risks (Us), Cls, and P values were reported or could be calculated were included. Four researchers independently extracted RRs, Cls, and P values from each study and evaluated the degree of confounding adjustment. The combined result was calculated with weighted average, and sources of disparity were tested with regression analyses. Results. The summary RR was 1.19 (95% Cl, 1.08 1.32), indicating a higher risk of future cardiovascular events in individuals with periodontal disease compared with those without. In an analysis stratified to individuals of less than or equal to65 years of age, the RR was 1.44 (95% Cl, 1.20 to 1.73). When the outcome was restricted to stroke only, the RR was 2.85 (95% Cl, 1.78 to 4.56). In the metaregression analysis, the effects of residual confounding caused an overestimate of the results by 12.9% and, with a proxy for periodontal disease, caused an underestimate of 29.7%. Conclusion. Periodontal disease appears to be associated with a 19% increase in risk of future cardiovascular disease. This increase in RR is more prominent (44%) in persons aged less than or equal to65 years. Although the increment of risk between subjects with or without periodontal disease in the general population is modest, at around 20% because nearly 40% of population has periodontal disease, this modest increase may have a profound public health impact.