Do urinary levels of vascular endothelial growth factor predict proliferative retinopathy?

Purpose. Vascular endothelial growth factor (VEGF) is elevated in the vitre ous of patients with proliferative retinopathies (PR). Angiogenic factors l ike VEGF are elevated in the urine of subjects with cancers, including thos e distant from the genitourinary tract. We hypothesized that local increase s in VEGF in the vitreous would be reflected in the urine of subjects with PR. Methods. Urine samples were collected from adults with absent, mild, or sev ere (requiring laser photocoagulation) PR. VEGF was measured by enzyme link ed immunosorbent assay. Results. Of 42 subjects, 16 had no PR and 26 had PR (8 mild, 18 severe). Th irty subjects had diabetes mellitus; 24 of these had PR. Subjects with PR w ere older than controls. Subjects with PR tended to have higher urinary VEG F (median 123 pg/ml Cr, range 3-1738) than controls without PR (median 93 p g/ml Cr, range 2-200) (p = 0.08). None of 16 controls, but 11/15 subjects w ith PR had >200 mg VEGF/mg Cr (p = 0.003), yielding high specificity (100%) , but poor sensitivity (42%) of elevated urinary VEGF for PR. Urinary VEGF was also modestly correlated with urinary protein excretion (r(2) = 0.23). Correction of VEGF values for urinary protein abrogated any correlation wit h PR. Conclusions. Urinary levels of VEGF are associated with PR, but this relati onship may be caused by concurrent renal diseases that result in proteinuri a and/or renal VEGF production. The insensitivity of the association may pr eclude its use in screening to avoid eye examinations.