GDF-15 Levels in Gouty Arthritis and Correlations with Decreasing Renal Function: A Clinical Study.

Background/Objectives: Gouty arthritis (GA) is a chronic inflammatory disorder frequently linked to systemic inflammation and impaired kidney function. Growth differentiation factor-15 (GDF-15) has been suggested as a potential biomarker involved in both inflammatory responses and renal dysfunction. Studies on GDF-15 serum levels and renal function decline in GA patients are limited. This study aimed to investigate serum GDF-15 levels in patients with GA and to evaluate the relationship between GDF-15 and renal function parameters. Methods: This prospective case-control study included 60 (intercritical group: 30; acute attack group: 30) patients with gout arthritis and 60 healthy controls, matched for body mass index and sex. The enzyme-linked immunosorbent assay measured serum GDF-15, and renal function and inflammatory markers were also assessed. Group comparisons used non-parametric tests, Spearman's analysis evaluated correlations, and receiver operating characteristic (ROC) analysis assessed diagnostic performance. Results: Serum GDF-15 levels were significantly higher in GA patients than controls (p < 0.001), especially during acute attacks. GDF-15 correlated moderately with renal function markers. ROC analysis showed high diagnostic accuracy for both acute (area under the curve (AUC) = 0.98) and intercritical gout phases (AUC = 0.96). Conclusions: Serum GDF-15 levels are increased in patients with gouty arthritis and are associated with impaired renal function. GDF-15 may serve as a helpful biomarker for disease activity and renal involvement in GA, but its interpretation should be considered in conjunction with other clinical and laboratory parameters.