Free inulin growth factor-I and vacular endothelial growth factor in the vitreou fluid of patient with proliferative diabetic retinopathy

PURPOE: To invetigate the relationhip between inulin-like growth factor-I (IGF-I) and vacular endothelial growth factor (VEGF) in the vitreou fluid of diabetic patient with proliferative diabetic retinopathy (PDR). DEIGN: Obervational cae-control tudy. METHOD: In a propective tudy, 37 conecutive diabetic patient with PDR (14 type I and 23 type II diabete mellitu) in whom a vitrectomy wa performed were compared with 21 nondiabetic patient with other condition requiring vitrectomy (control group). Free IGF-I and VEGF were meaured by ELIA. REULT: Vitreal level of both free IGF-1 and VEGF were higher in diabetic patient with PDR than in control ubject (P < .01, and P < .0001, repectively). After adjuting for total intravitreou protein concentration, VEGF (ng/mg of protein) remained ignificantly higher in diabetic patient with PDR than in the control group (P < .0001), wherea free IGF-I (ng/mg of protein) wa lower in diabetic patient than in control ubject (P < .0001). The vitreou concentration of VEGF were higher in patient with active PDR than in patient with quiecent PDR (P < .005), wherea vitreou free IGF-I wa not related to PDR activity. Finally, we did not oberve a correlation between the vitreal level of free IGF-I and VEGF. CONCLUION: We conclude that free IGF-I and VEGF are both increaed, but not related, within the vitreou fluid of diabetic patient with PDR. In addition, our reult upport the current concept that VEGF i directly involved in the pathogenei of PDR, wherea the precie role of free IGF-I remain to be etablihed.