This record is a critical summary produced by NHS Evidence - oral health. 



Authors’ conclusions: We did not find any direct evidence that periodontal examination would be useful for reclassifying persons classed as intermediate-risk by the Framingham risk score.
The weight of currently existing evidence suggests that there may be an important link between periodontal disease and CHD. Additional longitudinal studies with standardized measures of periodontal disease and careful adjustment for socioeconomic status as well as for traditional CHD risk factors would be useful.

Methods: A systematic review and meta-analysis of 76 prospective cohort studies. The review identified 8 papers from 7 cohorts that were relevant to periodontal disease. Database search 1966-2006 inclusive.

Quality of review: It is possible that potentially relevant papers were missed as the authors searched only one electronic database (PubMed), using very limited terms, supplemented by reference list checking. The search was further limited to English language published studies. No information is provided on the methods used to select, data extract and critically appraise included studies and the introduction of error and bias cannot be excluded. The authors used the US Preventive Services Task Force criteria to critically appraise included papers. Five were considered good quality and three were deemed fair quality

The authors note several issues including: Lack of reliability in assessment of PD. Mix of measures and self report. Also that periodontal examination requires skill with dental instruments and x-rays and the wide range of possible measures. Lack of evidence in intermediate-risk populations; particularly in ethnic groups.

Results: Follow-up ranged between 5 and 21 years. Periodontal disease was defined (and diagnosed) differently among the studies. Some studies employed dental examinations and radiographs and others relied on self report. Cardiovascular and CHD outcomes also were defined differently among the studies. Three studies were rated good quality and five were fair quality. Periodontal disease based on either self report or dental examinations was evaluated in 6 studies. Five studies showed increased risk of CHD in association with baseline periodontal disease and two showed no association, although one study found an increased risk that was not statistically significant (RR 1.5) among women. When these studies were combined in meta-analysis, the summary estimate of risk ratio was 1.24 (95% CI 1.01-1.51) for any CHD or CVD event. In subgroup analyses, the association with CHD was increased with female gender, longer follow-up times, and in studies based on dental exam rather than self-report. Gingivitis as a measure of periodontal disease was evaluated in 2 studies and both showed or suggested elevated rates of CHD death among individuals with baseline gingivitis. When combined in meta-analysis the summary estimate was 1.35 (95% CI 0.79-2.30). Bone loss was an important risk factor for subsequent CHD with 2 studies showing statistically significant relative risks from 1.36-1.90. Four studies found that tooth loss made an independent contribution to the prediction of CHD events; one fair quality study suggested increased risk but was not statistically significant. When these 4 studies were combined in meta-analysis, the summary estimate for all CHD/CVD events was 1.41 (95% CI 1.22-1.63) indicating a 41% increased risk of CHD or CVD events among individuals with 0-10 teeth at baseline.

Citation: Helfand M, Buckley DI, Freeman M, Fu R, Rogers K, Fleming C, Humphrey LL. Emerging risk factors for coronary heart disease: a summary of systematic reviews conducted for the U.S. Preventive Services Task Force. Ann Intern Med. 2009 Oct 6;151(7):496-507.