Periodontal Disease and Coronary Heart Disease Karen Geismar,* Kaj Stoltze,* Bjarne Sigurd, † Finn Gyntelberg, ‡ and Palle Holmstrup* Background: Several epidemiological studies have demon- strated an association between periodontal disease and coro- nary heart disease (CHD). The association could be a result of confounding by mutual risk factors. The present study was undertaken in a Danish population to reveal the significance of common risk factors. Methods: The investigation was conducted as a case-control study comprising 250 individuals: 110 individuals with verified CHD from a Department of Cardiovascular Medicine and 140 control individuals without CHD from the Copenhagen City Heart Study. Information on diabetic status, smoking habits, alcohol consumption, physical activity, school attendance, household income, body weight and height, triglyceride, and serum cholesterol was obtained. Full-mouth probing depth (PD), clinical attachment loss (CAL), bleeding on probing (BOP), and alveolar bone level (ABL) on radiographs were registered. ABL was stratified into ABL1 = ABL £2 mm; ABL2 = ABL >2 to £4 mm; and ABL3 = ABL >4 mm. Multiple logistic regression models with stepwise backward elimination were used allowing variables with P <0.15 to enter the multi- variate analysis. Results: The CHD group had a significantly lower out- come with respect to PD, BOP, CAL, and ABL. For participants <60 years old, only risk factors such as smoking and diabetic status entered the multivariate analysis. For the ABL3 group, there was a significant association with CHD for participants <60 years old, the odds ratio being 6.6 (1.69 to 25.6). For par- ticipants ‡60 years old, there was no association. Conclusions: The present study showed a positive associa- tion between periodontal disease and CHD in agreement with several other studies. The association was highly age depen- dent and could only be attributed to diabetes and smoking to some extent. J Periodontol 2006;77:1547-1554. KEY WORDS Case-control study; coronary heart disease; periodontal disease; risk factors. W ithin the past decade, epi- demiological studies have re- peatedly shown an association between periodontal disease and coro- nary heart disease (CHD). Periodontal disease and CHD are widespread condi- tions, and, therefore, an association be- tween them is an important scientific subject from a preventive point of view. Several studies have been conducted using cohort, cross-sectional, or case- control designs with varying conclusions on the strength of the association as re- viewed by Holmstrup et al. 1 Most of the results reporting a lack of association between periodontal disease and CHD are from prospective studies. In earlier studies, the measurement of periodontal disease has ranged from self- reported periodontal disease, partial recording of attachment, the number of teeth left, and the Russell plaque index to clinical attachment loss (CAL) and al- veolar bone level (ABL), but no studies have been based on full-mouth registra- tion of CAL and registration of ABL to our knowledge. It has been suggested that the spread of bacteria and bacterial products from the periodontal lesion to the bloodstream may contribute to arteriosclerosis and CHD. 2,3 However, whether an associa- tion between periodontal disease and CHD could be causal is still uncertain. Another explanation for the observed as- sociation could be that the two disease entities share common risk factors. For CHD, several modifiable and non-modifiable factors, such as elevated * Department of Periodontology, School of Dentistry, Faculty of Health Science, University of Copenhagen, Denmark. † Department of Cardiovascular Medicine, Rehabilitation Unit, Bispebjerg University Hospital, Copenhagen, Denmark. ‡ Clinic of Environmental and Occupational Medicine, Bispebjerg University Hospital. doi: 10.1902/jop.2006.050405 J Periodontol • September 2006 1547