Cardiovascular Risk Factors and Acute-phase Response in Idiopathic Ascending Aortitis: a Case Control Study

Introduction: Idiopathic aortitis is a rare condition characterized by giant cell or lymphoplasmacytic inflammation of the aorta. The purpose of this study was to describe risk factors for the development of idiopathic aortitis.

Methods: We conducted a case control study of 50 patients who were age-matched with two control subjects with non-inflammatory ascending aortic aneurysms. We examined whether the prevalences of gender, hypertension, hyperlipidemia, diabetes mellitus, smoking, family history of any aortic aneurysms, and elevated inflammatory markers differed between cases and controls.

Results: The mean age of cases was 71.6 +/- 8.9 years and that of controls was 71.1 +/- 8.9 years. We found female gender (odds ratio [OR] 2.41, 95% confidence interval [CI] 1.20 to 4.85; P = 0.014) and active smoking (OR 3.37, 95% CI 1.12 to 10.08; P = 0.03) to be associated with idiopathic aortitis. The association with smoking persisted after adjustment for gender (OR 3.24, 95% CI 1.05 to 9.96; P = 0.04). There was a trend toward lower prevalence of diabetes mellitus in cases (OR 0.39, 95% CI 0.11 to 1.43; P = 0.16) but no difference in prevalences of other risk factors. The median pre-operative erythrocyte sedimentation rate (ESR) was 20 mm/hour in cases (n = 13) and 9 mm/hour in controls (n = 22). The median pre-operative C-reactive protein (CRP) levels were 12 mg/L in cases (n = 8) and 3 mg/L in controls (n = 6) (normal: <8 mg/L). A higher proportion of cases versus controls had elevations in ESR (38% versus 9%; P = 0.075) and CRP (62% versus 0%; P = 0.031).

Conclusions: Gender and smoking may interact in complex mechanisms with immune and proteolytic pathways in older, less distensible thoracic aortas. Elevated acute-phase reactants as a marker of systemic inflammation may be present in some patients.