ABC | Volume 114, Nº2, February 2020

Original Article Rocha et al. Association between periodontitis, polymorphisms and CAD Arq Bras Cardiol. 2020; 114(2):268-272 Table 1 – Variables analyzed by chi-square with CAD as outcome Analyzed variables CAD n = 80 OR CI (95%) p Present (%) Absent (%) Min. Max. Age ≥ 60 years 31 (59.6) 10 (35.7) 2.65 1.02 6.87 0.04 ≤ 59 years 21 (40.4) 18 (64.3) Gender Male 32 (61.5) 9 (32.1) 3.37 1.28 8.9 0.01 Female 20 (38.5) 19 (67.9) Overweight and obesity BMI ≥ 25 30(57.7) 22 (78.6) 2.68 0.93 7.73 0.35 BMI ≤ 24 22 (42.3) 6 (21.4) Ethnicity White 45 (86.5) 22 (78.6) 1.75 0.52 5.84 0.06 Non-White 7 (13.5) 6 (21.4) Periodontitis Present 26 (50%) 6 (21.4) 3.66 1.27 10.5 0.01 Absent 26 (50%) 22 (78.6) CRP +1444 C>T RS 1130864 T Allele 43 (82.7) 12 (42.9) 6.37 2.25 17.9 0.001 Non T allele 9 (17.3) 16 (57.1) IL6-174 G>C RS 1800795 C Allele 30 (57.7) 9 (32.1) 2.87 1.09 7.55 0.029 Non C allele 22 (42.3) 19 (67.9) CAD: coronary artery disease; OR: Odds Ratio, CI: confidence interval, significant when the range does not contain the unit. significant p-value < 0.05. Source: The author. regarding the association between periodontitis and CAD, with the influence of other independent covariates, it was decided to keep them, in view of the contribution of adjustments in logistic regression models. The presence of periodontitis in the bivariate analysis was significantly associated with CAD (p = 0.013; OR = 3.66 CI (95%) 1.27-10.5). This association has been studied for decades. A cross-sectional study with 60,174 participants that analyzed the association between periodontitis and CAD found a statistically significant association between the two conditions with an odds ratio of 1.59 and CI (95%) between 1.31 and 1.81, after adjustment for confusion factors. 23 In the present study we verified the association between periodontal inflammation and polymorphisms (IL6 and CRP) aiming to verify its possible association with CAD. We observed a strong association (p = 0.001) between the presence of the PCR + 1444 C > T polymorphism, risk allele T and the case group with OR = 6.37; (95%) 2.25 - 17.9, which contradicts authors who analyzed five studies, totaling 18,637 participants, where the PCR + 1444 C > T polymorphism was adjusted for confounding factors and compared regarding the presence of CAD, but found no association between this polymorphism and coronary disease. 24 It is possible to infer that this association may arise from CRP serum levels maintained by chronic periodontitis over several years. The presence of this association is corroborated by studies comparing the size of atherosclerotic plaques in relation to the PCR polymorphism at this SNP (+1444 C > T) in 196 patients with CAD from a database of studies evaluating the use of nitrates (ENCORE) in Switzerland, concluding that the carriers of this polymorphism were independently prone to larger plaque volumes. 15 These results lead us to believe that somehow the presence of this polymorphism, probably through CRP serum levels, acts directly in the atherosclerotic process, as indicated by recent studies. 25,26 The IL6 -174G>C polymorphismwas statistically associated with the presence of CAD (p = 0.025, OR = 2.87 CI (95%) Table 2 – Variables adjusted by logistic regression Variables Chi-square Logistic regression p OR CI (95%) p OR CI (95%) Min. Max. Min. Max. Age ≥ 60 years 0.04 2.65 1.02 6.87 0.02 3.6 1.14 11.3 Male gender 0.01 3.37 1.28 8.91 0.37 1.71 0.51 5.67 Periodontitis present 0.01 3.66 1.27 10.5 0.16 2.47 0.68 8.9 CRP +1444 polymorphism 0.001 6.37 2.25 17.9 0.014 4.31 1.34 13.8 IL6 -174 polymorphism 0.029 2.87 1.09 7.55 0.06 2.94 0.94 9.19 Significant p-value < 0.05; OR: Odds Ratio; CI: confidence interval, significant when the range does not contain the unit. Source: The author. 270