The effect of periodontal therapy on C-reactive protein, endothelial function, lipids and proinflammatory biomarkers in patients with stable coronary artery disease: study protocol for a randomized controlled trial

BACKGROUND: Scarce information exists regarding the preventive effect of periodontal treatment in the recurrence of cardiovascular events. Prevention may be achieved by targeting risk factors for recurrent coronary artery disease (CAD) in patients with previous history of cardiovascular events. The aim of this trial is to compare the effect of two periodontal treatment approaches on levels of C-reactive protein, lipids, flow-mediated dilation and serum concentrations of proinflammatory and endothelial markers in stable CAD patients with periodontitis over a period of 12 months. METHODS/DESIGN: This is a randomized, parallel design, examiner blinded, controlled clinical trial. Individuals from both genders, 35 years of age and older, with concomitant diagnosis of CAD and periodontitis will be included. CAD will be defined as the occurrence of at least one of the following events 6 months prior to entering the trial: documented history of myocardial infarction; surgical or percutaneous myocardial revascularization and lesion >50% in at least one coronary artery assessed by angiography; presence of angina and positive noninvasive testing of ischemia. Diagnosis of periodontitis will be defined using the CDC-AAP case definition (≥2 interproximal sites with clinical attachment loss ≥6 mm and ≥1 interproximal site with probing depth ≥5 mm). Individuals will have to present at least ten teeth present to be included. One hundred individuals will be allocated to test (intensive periodontal treatment comprised by scaling and root planing) or control (community periodontal treatment consisting of one session of supragingival plaque removal only) treatment groups. Full-mouth six sites per tooth periodontal examinations and subgingival biofilm samples will be conducted at baseline, 3, 6 and 12 months after treatment. The primary outcome of this study will be C-reactive protein changes over time. Secondary outcomes include levels of total cholesterol, LDL-C, HDL-C, triglycerides, IL-1β, IL-6, TNFα, fibrinogen, ICAM-1, VCAM-1 and E-selectin. These outcomes will be assessed at all time points over 12 months. Flow-mediated dilation will be assessed at baseline, 1, 3 and 6 months after periodontal therapy. DISCUSSION: This trial will provide new evidence regarding the effect of periodontal treatment on risk markers for recurrence of cardiovascular events in stable coronary artery disease patients. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Identifier, NCT01609725