Radiographic measures of chronic periodontitis and carotid artery plaque

Abstract

Background and purpose: Chronic periodontitis (CP) is associated with stroke and subclinical atherosclerosis, but clinical measurement of CP can be time consuming and invasive. The purpose of this study was to determine whether radiographically assessed CP is associated with nonstenotic carotid artery plaque as an ultrasound measure of subclinical atherosclerosis.

Methods: Panoramic oral radiographs were obtained from 203 stroke-free subjects ages 54 to 94 during the baseline examination of the Oral Infections and Vascular Disease Epidemiology Study (INVEST). CP exposure among dentate subjects was defined either categorically (periodontal bone loss > or =50% [severe] versus <50% bone loss) or via tertile formation (for dose-response investigation), with edentulous subjects categorized separately. In all subjects, high-resolution B-mode carotid ultrasound was performed. Carotid plaque thickness (CPT) and prevalence (present/absent) were recorded. Covariates included age, sex, smoking, diabetes, hypertension, low-density lipoprotein (LDL) cholesterol, and high-density lipoprotein cholesterol.

Results: Among dentate subjects with severe periodontal bone loss, mean CPT was significantly greater (1.20+/-1.00 mm versus 0.73+/-0.89 mm; P=0.003). CPT increased with more severe bone loss (upper versus lower tertile bone loss; P=0.049; adjusted for age, sex, and hypertension). This apparent dose-response effect was more evident among never-smokers. In a fully adjusted multivariate logistic regression model, severe periodontal bone loss was associated with a nearly 4-fold increase in risk for the presence of carotid artery plaque (adjusted odds ratio, 3.64; CI, 1.37 to 9.65).

Conclusions: Severe periodontal bone loss is associated independently with carotid atherosclerosis. Panoramic oral radiographs may thus provide an efficient means to assess CP in studies of atherosclerosis risk.

Figure 1

Frequency distribution of mean whole mouth periodontal bone loss score among dentate subjects (n=169). Median bone loss score 1.45 (interquartile range 1.25 to 1.91).

Figure 2

Mean carotid plaque thickness [log(CPT+1)] by periodontal bone loss tertile, and edentulous status. Normalized CPT values were significantly greater for subjects in the highest bone loss tertile versus the lowest bone loss tertile, adjusting for age, sex, smoking, and hypertension (P=0.049 by ANCOVA).

Figure 3

Normalized CPT values were significantly greater among former and current smokers, P<0.0001. Among never smokers, normalized CPT values were significantly greater for subjects in the highest bone loss tertile versus lowest bone loss tertile, P=0.015, and highest bone loss tertile versus edentulous, P=0.018, adjusted for age, sex, and hypertension.