Abstract 5108: Microalbuminuria is Associated with Progression of Coronary Atherosclerosis in the Multi-Ethnic Study of Atherosclerosis (MESA)
Background: Microalbuminuria (MA) is associated with an increased risk of cardiovascular disease (CVD) but the mechanism by which microalbuminuria imparts this increased risk is not known. In this study we assessed the relationship between MA and the development and progression of atherosclerosis by measuring the incidence of new CAC and the progression of existing CAC in individuals free of clinical CVD.
Methods: The Multi-Ethnic Study of Atherosclerosis (MESA) is a prospective cohort study of 6,814 participants free of clinical CVD at entry who underwent assessment of coronary artery calcification (CAC) by computerized tomography at baseline. Overall, 6,775 individuals had data available on urinary albumin creatinine ratio (UACR); 1,109 individuals were excluded for missing data or macroalbuminuria (UACR≥300 mg/g). Incident CAC was defined as detectable CAC at follow-up among those with CAC=0 at baseline, and absolute CAC score change among those with CAC>0 at baseline. Relative risk (RR) regression adjusted for covariates; and multivariable adjusted median regression was employed to assess the independent relationship of MA with CAC incidence and progression.
Results: Of the 5,666 subjects (mean age 62±10 years, 48% males), baseline MA was seen in 424 (7%) participants, who were more likely to have CAC compared to those with normal UACR (62% vs. 48%, p<0.0001). During a mean follow-up of 2.4±0.8 years, those with MA were more likely to develop CAC (28% vs. 15%, p<0.0001) and they had a higher absolute median increase in CAC (47 vs. 29 Agatston Units, p<0.0001). After adjustment for age, gender, ethnicity, site, follow-up duration, diabetes, hypertension, smoking, family history of heart attack, total cholesterol, lipid lowering medications and body mass index; MA was associated with incident CAC (RR 1.65; 95%CI 1.41–2.48) among those with CAC=0 at baseline. Among those with CAC>0 at baseline, MA was associated with a median increase in CAC of 7.93 (95%CI 0.38 –15.47) Agatston Units in multivariable adjusted analyses (variables noted above).
Conclusion: MA is independently associated with development of incident CAC and progression of CAC in an asymptomatic multi-ethnic population, and may in part explain its associated increased risk of CVD.