Elevated serum levels of soluble vascular cell adhesion molecule-1 in NIDDM patients with proliferative diabetic retinopathy

We studied 68 Japanese NIDDM patients (38 men and 30 women), aged 56.9 +/- 1.2 years (range 33-75 years), with a BMI of 23.1 +/- 0.5 kg/m(2) without h ypertension, dyslipidemia, and diabetic macroangiopathy for evaluating the relationship between serum soluble vascular cell adhesion molecule-1 (sVCAM -1) levels and the severity of diabetic retinopathy. Fundus examination was performed by an ophthalmologist using an ophthalmoscope, and the findings were graded as: (1) no signs of diabetic retinopathy (NDR), (2) background diabetic retinopathy (BDR), or (3) proliferative diabetic retinopathy (PDR) . Serum sVCAM-1 levels were measured in duplicate by enzyme-linked immunoso rbent assay using the soluble VCAM-1 KIT (R&D Systems Ltd., Ablingdon, Oxfo rdshire, UK). There was no difference in serum sVCAM-1 levels between patie nts with BDR (n = 17) and patients with NDR (n = 40) (1035.3 +/- 104.4 and 978.8 +/- 48.9 ng/ml, respectively, P = 0.8), but patients with PDR (n = 11 ) showed a significant increase of serum sVCAM-1 levels compared with patie nts with NDR (1281.8 +/- 166.3 and 978.8 +/- 48.9 ng/ml, respectively, P = 0.02). Although serum sVCAM-1 levels were correlated, nob only with age but also with the known diabetic duration (r = 0.39, P = 0.001, and r = 0.40, P = 0.0007, respectively), age-adjusted sVCAM-1 levels were still significa ntly higher in the PDR group than in the NDR group. In contrast, serum sVCA M-1 levels were not related to the presence of diabetic nephropathy or HbA( 1c) levels. Our results suggest that sVCAM-1 might be implicated in the dev elopment of the diabetic retinopathy, and measurement of serum sVCAM-1 leve ls in NIDDM patients may be clinically useful for assessing the severity an d possibly the activity of diabetic retinopathy. (C) 1998 Elsevier Science Ireland Ltd. All rights reserved.