Associations between normal range albuminuria, renal function and cardiovascular function in a population-based imaging study.

BACKGROUND AND AIMS: In patients with impaired renal function and macroalbuminuria, cardiovascular risk factors are highly prevalent, however, whether this is also present in the general population is unclear. We investigated whether normal-range albuminuria and renal function are associated with cardiovascular function in the general population.

METHODS: In this cross-sectional analysis of the NEO study, urinary albumin-creatinine ratio (UACR), estimated glomerular filtration rate (eGFR), and intima-media thickness were assessed in all participants (n = 6503), and a random subset underwent MRI for pulse wave velocity (n = 2451) and/or cardiac imaging (n = 1138).

RESULTS: Multiple linear regression analysis was performed while adjusting for sex, age, smoking, mean arterial blood pressure, total body fat, and fasting glucose. After adjustment, albuminuria and renal function were positively associated with left ventricle (LV) mass index (UACR, 0.941 g/m2 [95% CI: 0.21,1.67] p = 0.012; eGFR, 0.748 g/m2 [95% CI: 0.15,1.35] p = 0.015) and LV cardiac index (UACR, 0.056 L/min/m2 [95% CI: 0.00,0.11] p = 0.038; eGFR, 0.080 L/min/m2 [95% CI: 0.03,0.13] p = 0.001). Albuminuria showed a weak association with arterial thickness (UACR, 0.003 mm [95% CI: 0.00,0.01] p = 0.015) and arterial stiffness (UACR, 0.073 m/s [95% CI: 0.01,0.13] p = 0.036), but not with renal function. No associations were observed for LV ejection fraction and LV diastolic function.

CONCLUSIONS: Normal-range albuminuria was positively associated with LV mass index, LV cardiac index, arterial thickness and arterial stiffness. Our findings support the hypothesis that even within normal range, albuminuria is a marker of cardiovascular health.