In 70 nonobese inpatients with Type 2 diabetes [body mass index (BMI): 24.0 +/- 4.4 kg/m(2)], we examined circulating monocyte chemoattractant protein (MCP)-1 as a candidate marker of atherosclerosis by comparison with established markers: serum high-sensitivity C-reactive protein (hsCRP), plasma fibrinogen, and combined carotid artery intimal-medial thickness (IMT). In addition, an association was sought between circulating MCP-1 and urinary albumin excretion (UAE), reflecting diabetic renal rnicroangiopathy. Serum MCP-1 was determined by enzyme-linked immunosorbent assay (ELISA). Patients were grouped by UAE: normoalbuminuria, below 30 nig/g of creatinine (Cr); microalbuminuria, 30 to 300 mg/g Cr; or macroalbuminuria, over 300 mg/g Cr. Serum MCP-1 for all participants, men, and women was 280.0 +/- 78.9, 269.0 +/- 68.8, and 294.9 +/- 87.9 pg/ml, respectively, showing no difference between genders. No correlation was noted between MCP-1 and hsCRP, fibrinogen, or carotid artery IMT. No correlation of MCP-1 was observed with age, duration of diabetes, fasting plasma glucose (FPG), hemoglobin (Hb) A(1c), BMI, diastolic blood pressure (DBP), or serum lipid concentrations, but significant correlations were found with systolic blood pressure (SBP; R=.2723, P=.0225) and with log(10)-transformed (log) UAE (R=.3343, P=.0047). Patients with macroalbuminuria had significant higher circulating MCP-1 than did those with normo- or microalbuminuria (P=.0063 and P=.0188, respectively). By stepwise regression analysis, only log UAE independently predicted serum MCP-1 (beta =.3700, P=.0020). Thus, in nonobese Type 2 diabetic patients, MCP-1 might not be a marker of atherosclerosis and might be influenced significantly by diabetic nephropathy. (c) 2006 Elsevier Inc. All rights reserved.