Vitamin C and antioxidants play a crucial role in endothelial function and may be a link for the known interaction of periodontitis and ischemic heart disease (CAD). This pilot study evaluates the association of gingival health, periodontitis, CAD, or both conditions with salivary and serum vitamin C and antioxidant levels. The clinical and periodontal characteristics, serum, and saliva samples were collected from 36 patients with periodontitis, 35 patients with CAD, 36 patients with periodontitis plus CAD, and 36 healthy controls. Levels of vitamin C, antioxidants, and C-reactive protein (hs-CRP) were assessed with a commercially available kit. The median concentrations of salivary and serum vitamin C and antioxidants (α-tocopherol, β-carotene, lutein, and lycopene) were significantly lower in the CAD group (p < 0.001) and in the periodontitis plus CAD group (p < 0.001) compared to periodontitis patients and controls. In univariate models, periodontitis (p = 0.034), CAD (p < 0.001), and hs-CRP (p < 0.001) were significantly negatively associated with serum vitamin C; whereas, in a multivariate model, only hs-CRP remained a significant predictor of serum vitamin C (p < 0.001). In a multivariate model, the significant predictors of salivary vitamin C levels were triglycerides (p = 0.028) and hs-CRP (p < 0.001). Patients with CAD and periodontitis plus CAD presented lower levels of salivary and serum vitamin C compared to healthy subjects and periodontitis patients. hs-CRP was a significant predictor of decreased salivary and serum vitamin C levels.
Keywords: C-reactive protein; cardiovascular disease; clinical trial; ischemic heart disease; lutein; lycopene; periodontitis; retinol; vitamin C; zeaxanthin; α-carotene; β-carotene; β-cryptoxanthin; γ-tocopherol.