The relationship between serum FGF-21, neuregulin-4 and leptin levels and disease severity in patients with psoriasis

Abstract

BACKGROUND: Psoriasis is an immune-mediated inflammatory disease accompanied by metabolic syndrome (MetS). FGF-21, leptin, Nrg-4, and hs-CRP may reflect cardiometabolic dysfunction. OBJECTIVE: To compare MetS prevalence and biomarker levels in psoriasis versus controls and assess associations with MetS and PASI. METHODS: This case-control study included 80 patients with psoriasis and 60 age- and sex-matched controls. MetS was defined by NCEP-ATP III criteria. Metabolic parameters and biomarkers were measured. Regression models were adjusted for age, sex, and BMI. RESULTS: MetS prevalence was higher in psoriasis than controls (43.8% vs 8.3%, p = 0.001), with greater adiposity, insulin resistance, and hs-CRP and lower HDL-C. Mean FGF-21, leptin, and Nrg-4 levels did not differ between groups (all p > 0.05). Among patients with psoriasis, MetS was associated with higher FGF-21 and leptin and lower Nrg-4 (all p ≤ 0.025). In adjusted analyses, MetS was associated with FGF-21 (aOR = 1.42 per 100 pg/mL), leptin (aOR = 1.18 per ng/mL), Nrg-4 (aOR = 0.79 per ng/mL), and hs-CRP (aOR = 1.21 per mg/L) (all p ≤ 0.006). PASI correlated moderately with FGF-21 and hs-CRP (r = 0.47 for both, p < 0.01), and both remained independently associated with PASI. CONCLUSIONS: Psoriasis was associated with a higher MetS burden. Although FGF-21, leptin, and Nrg-4 did not distinguish psoriasis from controls, their associations with MetS suggest cardiometabolic dysfunction rather than psoriasis-specific alterations. FGF-21 and hs-CRP were moderately associated with PASI. These cross-sectional findings do not establish causality or prognostic value.