Abstract 11163: Predictors of Abdominal Aortic Calcium Incidence: The Multi-Ethnic Study of Atherosclerosis
Abdominal aortic calcification (AAC) represents the early stages of subclinical atherosclerosis. AAC can be used to study the interplay between traditional and novel risk factors in development and progression of subclinical atherosclerosis before clinical cardiovascular disease becomes evident. To date, no population-based studies have assessed risk factors for incident AAC.
Methods: We assessed 648 individuals with AAC measurements by computed tomography at Exams 2 and 4 in the Multi-Ethnic Study of Atherosclerosis (MESA). Among 218 participants with no AAC at Exam 2, logistic regression was used to identify risk factors associated with the development of AAC. Standard risk factors (age, sex, ethnicity, smoking prevalence, pack years of smoking, LDL and HDL cholesterol, systolic blood pressure (SBP), body mass index (BMI), and diabetes) in addition to inflammation markers C-reactive protein (CRP), interleukin-6 (IL-6), and fibrinogen were measured at baseline.
Results: During a mean follow-up of 3.2 years, 58 subjects (26.6%) developed incident AAC. Significant risk factors for incident AAC included age, pack-years of cigarette smoking, fibrinogen, and alcohol use. Age (Odds Ratio (OR): 2.1 per 10 years, 95% Confidence Interval (CI):1.5–3.8) and pack-years of cigarette smoking (OR 2.2 per 20 pack years, 95% CI: 1.2–4.0) were positively associated, while alcohol use was inversely associated (OR 0.94 per drink/week, 95% CI: 0.88–1.00) after adjustment for gender, ethnicity, time between scans, BMI, LDL, SBP, and diabetes. Fibrinogen (OR 1.12 per 20 mg/dL, 95% CI:1.00-1.25) but not log [CRP[ (OR 1.05, 95% CI: 0.73–1.52) or log[IL-6[ (0.89, 95% CI:0.40–1.96) was associated with incident AAC when added to the above multivariable model.
Conclusions: In the MESA cohort, incident aortic calcium was independently associated with age, smoking, and fibrinogen levels while inversely associated with alcohol use. In contrast, neither CRP nor IL-6 showed a significant association with AAC incidence. These data suggest important relationships between lifestyle factors, smoking and alcohol use, and haemostatic/inflammation marker, fibrinogen, on early incident subclinical atherosclerosis.
- © 2010 by American Heart Association, Inc.