The predictive value of urinary vascular endothelial growth factor (VEGF) on worsening kidney function in proteinuric chronic kidney disease

Objectives: To evaluate the role of urinary vascular endothelial growth factor (VEGF) as an early predictor of chronic kidney disease (CKD) progression in patients with glomerular diseases. Methods: We prospectively included patients with proteinuria and CKD grade 1 - 5 due to glomerular disease at the time of kidney biopsy. At baseline, we collected demographics, comorbidities, smoking history, serum creatinine (sCr), proteinuria, and urinary VEGF in collected 24-hour urine. The primary outcome was a 50% increase in sCr at last follow-up. Binary regression was used to explore the impact of urinary biomarkers adjusted for baseline patient characteristics on the outcome. Results: From July 2011 to September 2012 we included 49 patients aged 45.2 +/- 14.8 years, 43% female, with different glomerular diseases. We followed them for 29 +/- 11 months. Twelve out of 49 (22%) patients met the primary outcome. The patients with a 50% increase in sCr at last follow-up had a significantly higher baseline sCr (193 +/- 101 vs. 127 +/- 84; p = 0.014) and higher urinary VEGF/creatinine in 24-hour urine (7.7 +/- 6.4 vs. 3.0 +/- 4.0; p = 0.005). When we added both sCr and urinary VEGF/creatinine to the binary regression model, the correlation with baseline sCr was not significant (OR 1.01; 95% CI 1.00 - 1.01; p = 0.184), while urinary VEGF/creatinine remained significant (OR 1.18; 95% CI 1.04 - 1.35; p = 0.008). Baseline patient characteristics, such as age, gender, body mass index, sCr, proteinuria, smoking status, histopathologic diagnosis, concomitant arterial hypertension, and time to last follow-up did not influence the primary outcome. Conclusions: The urinary VEGF/creatinine ratio in 24-hour urine seems to independently predict worsening of chronic kidney disease in patients with glomerular diseases.