Circulating levels of fibroblast growth factor 21 in early-stage diabetic kidney disease

Aims/purpose: Fibroblast growth factor 21 (FGF21), a hepatoadipokine with pleiotropic metabolic regulatory actions, is emerging as a novel biomarker of progressive nephropathy. We sought to evaluate circulating FGF21 and its association with clinical and biochemical characteristics as well as the urinary albumin excretion (UAE) rates in a population of patients with type 2 diabetes (T2D) with or without microalbuminuria and their matched healthy controls. Methods: Cross-sectionally, 130 consecutive individuals comprising patients with T2D with (n = 44) or without (n = 44) microalbuminuria and their healthy controls (n = 42) were recruited for analysis. Various demographic, clinical and biochemical parameters were assessed. Results: Serum FGF21 levels were significantly elevated in patients with microalbuminuria [median (interquartile range, IQR): 269.50 (188.50) pg/mL] compared to their normoalbuminuric peers with T2D [median (IQR): 103.50 (75.75) pg/mL] and nondiabetic people [median (IQR): 99.00 (126.75) pg/mL]. While serum FGF21, diastolic blood pressure and duration of diabetes mellitus (DDM) were independently associated with microalbuminuria in the baseline logistic regression model, FGF21 and DDM emerged as significant correlates in the multivariate adjusted model (OR for FGF21 = 1.060, 95% CI = 1.011–1.110, P < .016). Conclusions: Serum FGF21 level is strongly associated with early-stage diabetic kidney disease in the high-risk population of patients with T2D (particularly with circulating FGF21 values rising above 181 pg/mL). The association of serum FGF21 with subclinical stages of diabetic nephropathy may unearth perspectives on early detection and prevention of the advanced stages of chronic diabetes microvascular complications through effective FGF21-targeted therapy.