Serum galectin-3 as a biomarker of metabolic syndrome, cardiovascular risk, and total mortality

Galectin-3 (gal-3), a beta-galactose binding protein, involved in chronic inflammation and fibrosis, has been associated with cardiovascular diseases (CVDs), chronic kidney disease (CKD), diabetes (DM), female sex and older age, and proposed as a biomarker for CVD- and total mortality. We aimed to examine cross-sectional associations of serum gal-3 with CVD-related factors and morbidity (n = 600, age 62–68 years, 50% female), and longitudinal associations with mortality, in subjects with and without CVDs, DM or CKD, over a nearly 10-year follow-up. We observed positive associations of gal-3 with older age, female sex, reduced kidney function, higher circulating inflammatory marker concentrations, greater cardiovascular morbidity and increased risk of total- and CVD mortality. The observed associations were almost entirely attenuated in subjects without baseline CVDs, CKD or DM, where higher gal-3 concentrations were only associated with higher BMI and greater waist circumference. Gal-3 concentrations are strongly mediated by demographic factors and morbidities such as CVDs, CKD and DM. Although higher gal-3 concentrations are associated with greater mortality risk, the association is not independent of key established risk factors. These findings suggest gal-3 levels primarily reflect total morbidity and overall risk, rather than acting as an independent marker for total- or CVD mortality.