Background: Urinary liver-type fatty acid-binding protein (L-FABP) is a promising diagnostic and prognostic biomarker for both acute and chronic kidney injury. Furthermore, this protein has been shown to possess antioxidant properties and appears to provide a prognostic value for cardiovascular morbidity and mortality in different clinical settings. The aim of the current study was to evaluate its relationship to inflammation and arterial stiffness in coronary artery disease (CAD) patients without reduced kidney function and in healthy controls.

Methods: We studied 52 patients with CAD (age 63.2 ± 9.2 years) and 41 clinically healthy controls (age 60.1 ± 7.2). Urinary L-FABP, serum adiponectin and resistin levels were measured using the enzyme-linked immunosorbent assay method. The technique of applanation tonometry was used for non-invasive pulse wave analysis and pulse wave velocity assessments.

Results: Higher carotid-femoral pulse wave velocity (cf-PWV) was observed in the CAD patients as compared to the controls (9.7 ± 2.6 vs. 8.2 ± 1.7 m/s; P=0.003). The two groups also differed in adiponectin (5701 ± 2890 vs. 7081 ± 3612; P=0.045) and resistin (3.4 (2.6–4.5) vs. 2.8 (2.4–3.5); P=0.043) levels. There was a positive relationship between log-L-FABP and cf-PWV (r=0.46, P=0.001) in subjects with CAD, which remained significant after adjustment for potential confounders. Log-L-FABP also correlated with serum adiponectin levels in the patient group (r=0.35, P=0.015).

Conclusions: Our findings suggest that urinary L-FABP might be independently associated with aortic stiffness and adiponectin in individuals with CAD.