Objective: Whereas circulating levels of C-reactive protein (CRP) have been associated with, for example, arterial stiffness, subclinical atherosclerosis and metabolic syndrome, other inflammatory biomarkers with potential interest for these conditions may not be measurable systemically. The predictive value of salivary biomarkers in these contexts has remained largely unexplored. The aim of the present study was to establish the association of different salivary biomarkers of inflammation with subclinical cardiovascular disease.
Methods: Two hundred and fifty-nine individuals were included in the study. Saliva and plasma samples were collected, and each individual underwent carotid ultrasound and measures of pulse wave velocity and blood pressure. Medical history of previous cardiovascular disease, current medications and smoking were collected by questionnaire.
Results: Salivary levels of CRP, leukotriene B4 (LTB4), prostaglandin E2 (PGE2), matrix metalloproteinase 9 (MMP-9), creatinine and lysozyme were measured. Salivary levels of CRP were significantly correlated with plasma levels (r = 0.73, P < 0.0001). In an age-adjusted and sex-adjusted analysis, salivary CRP was significantly and positively correlated with mean arterial blood pressure, pulse pressure, pulse wave velocity, BMI, metabolic syndrome, waist-to-hip ratio and intima-media thickness. Increasing age and sex-adjusted salivary CRP tertiles were in addition associated with carotid plaques. In a multivariate analysis, CRP and MMP-9 were associated with intima-media thickness, LTB4 and PGE2 with arterial stiffness, and lysozyme with hypertension.
Conclusion: Saliva may represent an alternative mean for evaluation of cardiovascular risk.