Journal of Periodontology; Copyright 2015 DOI: 10.1902/jop.2015.150353 1 Salivary Lipid Peroxidation in Patients With Generalized Chronic Periodontitis and Acute Coronary Syndrome Thuy T. Nguyen, DDS *† ; Lan Q. Ngo, DDS, PhD ‡ ; Ananya Promsudthi, DDS, MS § ; Rudee Surarit, PhD * * Department of Oral Biology, Faculty of Dentistry, Mahidol University, Bangkok, Thailand. † Department of Periodontology, Faculty of Odonto-stomatology, University of Medicine and Pharmacy – Ho Chi Minh City, Ho Chi Minh City, Vietnam. ‡ Department of Dental Basic Sciences, Faculty of Odonto-stomatology, University of Medicine and Pharmacy – Ho Chi Minh City, Ho Chi Minh City, Vietnam. § Department of Oral Medicine and Periodontology, Faculty of Dentistry, Mahidol University, Bangkok, Thailand. Background: Lipid peroxidation is a major consequence of oxidative stress and could be evaluated via malondialdehyde (MDA) levels. The present study aimed to assess MDA levels in the saliva of patients with chronic periodontitis (CP) and acute coronary syndrome (ACS) and to establish their correlation to periodontal clinical parameters, serum high sensitivity C-reactive protein (hsCRP), and plasma fibrinogen. Methods: The study enrolled 64 patients (32 men and 32 women, aged from 33 to 74 years) stratified into four age- and sex-matched groups as follows: 16 with both ACS and CP (the ACSCP group), 16 with ACS only (the ACS group), 16 with CP only (the CP group), and 16 healthy controls. All patients were examined, their periodontal clinical parameters recorded, and saliva and blood samples collected. Salivary MDA levels were measured using a spectrophotometric assay. A quantitative turbidimetric test was used for the measurement of serum hsCRP levels, whereas plasma fibrinogen levels were determined using an automatic analyzer. Results: Salivary MDA levels were significantly higher in patients with both ACS and CP than in those with only ACS or CP and in healthy controls (p<0.05). There were significantly positive correlations between salivary MDA levels and periodontal clinical parameters as well as biomarkers for cardiovascular events (p<0.001). Conclusions: This study was the first to investigate salivary MDA levels in ACS patients and their correlations to serum hsCRP and plasma fibrinogen levels. Our results indicated that salivary MDA level could be a biomarker for cardiovascular and/or periodontal diseases. KEY WORDS: saliva, lipid peroxidation, malondialdehyde, chronic periodontitis, acute coronary syndrome, biomarker Periodontitis is an inflammation of the gum that extends deep into the tissues, causing loss of supporting connective tissue and alveolar bone. 1 Bacteria in the biofilm are the primary etiologic factor of the disease, whereas environmental, behavioral, and genetic factors as well as host immune response are involved in the disease progression. 2 Chronic periodontitis (CP) is a common form of destructive periodontal diseases (PD) in adults and has been widely suggested to associate with numerous systemic diseases. 3 Recent studies have attempted to delineate the relationship between periodontitis and coronary heart disease (CHD) as implied by prior results. 4-7 Among different manifestation levels of CHD, acute coronary syndrome (ACS) represents a spectrum of events ranging from unstable angina pectoris to acute myocardial infarction (AMI), with or without ST elevation. 8 C-reactive protein (CRP) and fibrinogen are thought to have predictive values for ACS. 9,10 Although the clinical understanding of ACS pathophysiology has significantly improved in