Association between serum albumin, carotid atherosclerosis, and metabolic syndrome in Japanese individuals

Serum albumin is a maker of nutritional status and possesses antioxidative properties. Here, we have sought to investigate the mode of association between serum albumin levels, metabolic syndrome, and carotid atherosclerosis by analyzing the data of the cross-sectional data from 8143 individuals who underwent general health screening test. After adjusting for age, total cholesterol, and smoking status, the highest quartile of serum albumin (≥4.7 g/dL) was associated with increased prevalence of metabolic syndrome with an odds ratio of 1.80 (95% CI 1.41–2.23, P < 0.0001) in women, and 1.60 (95% CI 1.44–1.78, P < 0.0001) in men, when compared to the lowest serum albumin quartile (<4.3 g/dL). By contrast, when compared with the lowest quartile, the highest quartile of serum albumin was associated with reduced prevalence of carotid plaque with an odds ratio of 0.62 (95% CI 0.42–0.91, P < 0.001) in women, and 0.76 (95% CI 0.62–0.93, P < 0.01) in men, and for carotid intima-media thickening with an odds ratio of 0.57 (95% CI 0.35–0.94, P < 0.05) in women, and 0.71 (95% CI 0.55–0.92, P < 0.01) in men. Our data showed that higher serum albumin was inversely associated with the prevalence of early carotid atherosclerosis, although it was positively associated with the prevalence of metabolic syndrome. Whether these observations are in part explained by the antioxidative properties of albumin requires further investigation.