The association between albuminuria and coronary atherosclerotic burden in the general population

Albuminuria predicts cardiovascular events, but its association with prevalent subclinical coronary atherosclerosis is less well defined. We examined the cross-sectional relationship between urinary albumin-creatinine ratio (UACR) and coronary atherosclerotic burden in middle-aged adults from Sweden nationwide.

UACR was measured in fasting spot urine in 9424 SCAPIS participants from Uppsala and Malmö. Coronary atherosclerosis was quantified by coronary artery calcium score (CACS; n = 9277) and coronary computed tomography angiography (CCTA; n = 9187) for stenosis. Linear regression related log(UACR) to log(CACS) with sequential adjustment: Model 1 (age, sex, ethnicity, site), Model 2 (+blood pressure, antihypertensive treatment, diabetes and antidiabetic treatment), and Model 3 (+LDL cholesterol, lipid-lowering treatment, smoking status, and eGFR). Logistic regression examined prevalent calcification (CACS>0) and stenosis; subgroup analyses excluded CKD, cardiovascular disease, hypertension, and diabetes stepwise.

Higher UACR was associated with higher CACS in the full cohort: β = 0.21 (95% CI 0.14-0.27), 0.08 (0.01-0.15), and 0.07 (0.00-0.14) in Models 1-3, respectively. Associations persisted after excluding CKD and cardiovascular disease (n = 8448): β = 0.20 (0.13-0.27), 0.19 (0.12-0.26), and 0.07 (0.00-0.15). With further exclusions, Model 3 estimates attenuated and were non-significant (no CKD/cardiovascular disease/hypertension: β = 0.06 [-0.02 to 0.14]; additionally no diabetes: β = 0.05 [-0.03 to 0.14]). In Model 1, each log-increase in UACR was associated with higher odds of CACS>0 (OR 1.08, 95% CI 1.05-1.12) and stenosis (OR 1.04, 95% CI 1.01-1.08), but associations attenuated and were non-significant in Models 2-3.

Albuminuria is associated with greater coronary calcification burden, including in broadly healthy individuals, supporting the concept that albuminuria may reflect vascular disease early in the cardiovascular disease continuum.