Vitamin C in plasma and leucocytes in relation to periodontitis

Aim
To test the hypothesis that vitamin C concentrations in plasma, polymorphonuclear neutrophilic leucocytes (PMNs) and peripheral blood mononuclear cells (PBMCs) are lower in periodontitis patients compared with healthy controls.

Methods
Twenty-one untreated periodontal patients and 21 healthy controls matched for age, gender, race and smoking habits were selected. Dietary vitamin C intake was assessed by a self-administered dietary record. Fasting blood samples were obtained and analysed for vitamin C concentrations in plasma, PMNs and PBMCs by means of high-pressure liquid chromatography (HPLC).

Results
Plasma vitamin C was lower in periodontitis patients compared with controls (8.3 and 11.3 mg/l, respectively, p = 0.03). Only in the control group a positive correlation was present between vitamin C intake and plasma values. No differences could be assessed between patients and controls regarding vitamin C dietary intake and levels in PMNs and PBMCs. In the patient group, pocket depth appeared to be negatively associated with the vitamin C concentration in PMNs.

Conclusion
Although the relationship between low plasma vitamin C levels and periodontitis is clear, the disease cannot be explained by insufficient vitamin C storage capacity of leucocytes; the question remains through which mechanism low plasma vitamin C levels are related to periodontitis.