Background: Sera from patients with periodontal infections contain elevated levels of C-reactive protein (CRP) compared to periodontally healthy individuals. Most studies to date have included patients with chronic periodontitis, and few investigators have studied CRP levels in subjects with aggressive periodontitis (AgP). The purpose of this study was to determine the relative levels of serum CRP in AgP patients and periodontally healthy subjects and to examine patients' characteristics that might account for intergroup differences.
Methods: Serum samples were collected from 93 patients with generalized AgP (GAgP), from 97 patients with localized AgP (LAgP), and from 91 healthy controls (non-periodontitis [NP]). Periodontal examination consisted of plaque index, gingival index, probing depth, bleeding index, and attachment loss measurements. Current smoking was assessed by determination of serum cotinine levels by enzyme-linked immunosorbent assay (ELISA), and serum CRP levels were determined using a high-sensitivity ELISA assay.
Results: The three groups were significantly different from one another (P <0.0001). The 95% confidence interval for serum CRP concentrations were as follows: NP, 0.65919 (0.4901 to 0.8869); LAgP, 1.10138 (0.8265 to 1.468); and GAgP, 2.05318 (1.5313 to 2.7538) mg/l. CRP levels in both LAgP and GAgP subjects were significantly greater than those in NP subjects, and levels in GAgP were significantly greater than those in LAgP. Following adjustment of the data for periodontal and demographic variables and current smoking, both mean probing depth and periodontal diagnosis remained correlated with CRP levels.
Conclusions: Patients with AgP have statistically significant elevations in serum CRP levels compared to subjects without periodontitis. Elevated CRP in these subjects might represent a contribution of periodontal infections to systemic inflammation in relatively young individuals.