Objectives: Epidemiological studies have shown that serum fibroblast growth factor 21 (FGF21) levels were elevated in obesity and its related metabolic disorders. This prospective study assessed whether there was an independent association of serum FGF21 levels with all-cause and cardiovascular disease (CVD) mortality among patients with coronary artery disease (CAD).
Methods: A prospective cohort study of 1668 CAD patients was conducted. Their serum FGF21 levels were measured with ELISA kits. Cox regression models were used to estimate the association of serum FGF21 levels with the risk of mortality.
Results: During a median follow-up of 4.9 years, there were 194 deaths recorded and 130 of them were CVD deaths. Serum FGF21 levels positively correlated with age, body mass index, waist circumference, and adverse lipid profiles. Spline plots displayed a U-shaped association between serum FGF21 levels and all-cause as well as CVD mortality among CAD patients. Compared with serum FGF21 quartile 2, groups at quartiles 1, 3, and 4 had higher risk for all-cause and CVD mortality. Patients in the serum FGF21 quartile 4 had a 1.95-fold (95% confidence interval 1.25-3.02) risk of all-cause mortality and a 2.50-fold (95% confidence interval 1.43-4.38) risk of CVD mortality compared with those in quartile 2.
Conclusions: The present study is the first to demonstrate that both higher and lower serum FGF21 levels were associated with increased risks for all-cause and CVD mortality, independent of traditional CVD risk factors.