Calcified carotid artery atheromas in panoramic radiographs : diagnostic reliability and association to cardiovascular disease, diabetes and periodontitis

Sammanfattning: Objective: Incidental findings of Calcified Carotid Artery Atheromas (CCAA) on Panoramic Radiographs (PRs) of the jaws can be a risk marker for cardiovascular disease. The objectives for the thesis were to investigate the association between CCAA and 1) Myocardial Infarction (MI), 2) periodontitis, 3) diabetes and 4) estimated cardiovascular risk. Also 5) if patients with both CCAA and periodontitis have a higher risk of MI. The final objective was to study 6) General Dental Practitioners (GDPs) ability to detect CCAA on PRs and if a short training programme can improve their diagnostic accuracy.Materials and methods: Paper I-III were part of the Swedish, multicentre (17 hospitals) case- control study Periodontitis and Its Relation to Coronary Artery Disease (PAROKRANK). The study included 1610 individuals, 805 cases (151 women) diagnosed with first acute MI, and 805 controls matched for age, sex and residential area. Seventeen participants were not examined with PR and an additional 111 were excluded due to inadequate quality. As a result, 90 participants lost their match. Paper I and II had a case-control design that only included matched cases (n = 696) and controls (n = 696). Paper II and III used a cross-sectional design to evaluate all included cases (n = 738) and controls (n = 744) separately. All participants in PAROKRANK went through a detailed medical and oral health examination, including e.g., oral glucose tolerance, an extensive blood panel, and 4-point pocket probing. All PRs were assessed both for the presence of CCAA and signs of poor oral health, including marginal bone loss. The results from the medical examination were used to estimate risk of future cardiovascular events and death using Systematic COronary Risk Evaluation (SCORE) and Framingham Risk Score (FRS). The results from the oral health examination were used to classify the degree of periodontitis both according to bone loss and clinical periodontal disease index (CPDI). Paper IV used a pre-post design to evaluate 14 GDPs diagnostic accuracy regarding assessment of CCAA on PR before and after participation in a short training programme. The GDPs were evaluated at baseline, 2 weeks and 1 year after training. Comparisons were made with the consensus of 2 experienced oral and maxillofacial radiologists.Results: Paper I: CCAA on PRs was more common among cases with recent first MI, (33.8% with CCAA), compared to controls (27.6%; P = 0.012). Paper II: CCAA and CPDI were associated among cases (OR 1.51; 95% CI, 1.09 to 2.10; P = 0.02) and controls (OR 1.70; 95% CI, 1.22 to 2.38; P < 0.01). No association was found between CCAA and the degree of bone loss on PR. MI had a stronger association to CCAA combined with periodontitis, than to either condition alone (OR 1.75; 95% CI, 1.11 to 2.74; P = 0.01). Paper III: Elevated risk of a future cardiovascular event estimated with FRS was associated with CCAA, both among cases (OR 1.89; 95% CI: 1.31–2.73, P = 0.001) and controls (OR 1.64; 95% CI: 1.03–2.64, P = 0.04). Elevated risk of cardiovascular death according to SCORE was associated with CCAA among controls (OR 1.58; 95% CI: 1.12–2.23, P < 0.01) but not among cases. Diabetes was more common among controls with than without CCAA (18.0% vs. 11.7%), but this association was not statistically significant after adjustments. Paper I-III included a sex- stratified analysis revealing that the results were mainly applicable on men. Paper IV: An improvement in diagnostic accuracy was observed among GDPs after a short training programme for diagnosing CCAA on PR. The sensitivity increased (41.8% to 55.7%, P = 0.02) without a decrease in specificity. The kappa values also increased (0.66 to 0.71, P = 0.04). At 1 year follow up, the improvements compared to baseline remained.Conclusions: There is an association between CCAA on PR and MI. Clinically diagnosed periodontitis is associated with CCAA on PR, and among participants with both periodontitis and CCAA there is a higher probability of having had MI than among participants with either condition alone. An increased estimated risk of future cardiovascular events and death according to FRS and SCORE is associated with CCAA on PR. These conclusions are mainly applicable on men. Diabetes was not independently associated with CCAA on PR, possibly due to selection bias. A short training programme can significantly and sustainably improve GDPs diagnostic accuracy regarding CCAA. This indicate that GDPs could contribute to prevention of cardiovascular events and death by detecting CCAA on PR and, should be encouraged to refer patients without previous treatment of cardiovascular disease for further medical attention, and if other cardiovascular risk factors are identified, necessary treatment.