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 1 retrospective), in which relative risks (RRs), CIs, and P values were reported or could be calculated were included. Four researchers independently extracted RRs, CIs, 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% CI, 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 </=65 years of age, the RR was 1.44 (95% CI, 1.20 to 1.73). When the outcome was restricted to stroke only, the RR was 2.85 (95% CI, 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%.
Conclusions: 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 </=65 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.