PLASMA-CONCENTRATION OF IMMUNOREACTIVE VASCULAR ENDOTHELIAL GROWTH-FACTOR AND ITS RELATION TO SMOKING

We determined the plasma concentration of immunoreactive vascular endo thelial growth factor (IR-VEGF) and searched for a relationship betwee n it and the degree of microangiopathy, The plasma VEGF level was meas ured using an enzyme immunoassay in 110 non-insulin-dependent diabetes mellitus (NIDDM) patients with varying degrees of nephropathy or reti nopathy (RP) and in 39 healthy controls and 30 nondiabetic patients fo r comparison. One fourth of the control subjects, 60% of whom were cur rently smokers, had plasma levels of IR-VEGF higher than the lower lim it (15.6 pg/mL) of detection for this assay, whereas this was the case in half of the NIDDM patients, Plasma IR-VEGF was detectable in all p atients with cerebral infarction, chronic renal failure, and severe in fection, suggesting that tissue hypoxia might be a common cause for th e elevation of plasma VEGF in these disorders. The prevalence of measu rable plasma IR-VEGF levels increased in parallel with increases in th e urinary albumin excretion rate ([UAER] 35.1% for UAER <30 mg/24 h, 5 4.8% for UAER 30 to 300 mg/24 h, and 61.3% for UAER > 300 mg/24 h; P < .05 v UAER < 30 mg/24 h). The mean measurable plasma concentration te nded to increase with increasing UAER, However, there was no such corr elation with the severity of RP. Smoking caused an acute increase of p lasma IR-VEGF in only 22.6% (12 of 53) of the patients with a smoking habit. In conclusion, these findings suggest that circulating IR-VEGF may be linked to the progression of nephropathy, and smoking may facil itate this process by causing tissue hypoxia in susceptible patients. Copyright (C) 1998 by W.B. Saunders Company.