Results of blood inflammatory markers are associated more strongly with toe-brachial index than with ankle-brachial index in patients with type 2 diabetes.

Abstract

Three blood markers of inflammation (high-sensitivity C-reactive protein [hsCRP], interleukin [IL]-6, and fibrinogen) were compared with markers of atherosclerotic cardiovascular disease (CVD) (history of stroke or cardiac ischemia and measured toe-brachial index [TBI]) to determine whether inflammatory markers are associated with atherosclerosis in patients with type 2 diabetes. Of 103 patients with type 2 diabetes, 26 had CVD. TBI was plethysmographically determined in both great toes. Serum hsCRP was immunonephelometrically determined. Plasma IL-6 was measured by an enzyme immunoassay. Both ABI and TBI were lower in diabetic patients with CVD than in those without CVD (1.05 +/- 0.19 vs. 1.14 +/- 0.09, P < 0.05, and 0.75 +/- 0.20 vs. 0.95 +/- 0.21, P < 0.001, respectively). By linear regression, right TBI but not right ABI showed a significant negative correlation with serum hsCRP (r = -0.372, P < 0.01) and plasma fibrinogen (r = -0.224, P < 0.05). Serum hsCRP was also negatively correlated with lower TBI, but not lower ABI. We found no significant correlation between plasma IL-6 and ABI or TBI. TBI was strongly associated with CVD, serum hsCRP, and plasma fibrinogen. Of these inflammatory markers, serum hsCRP may be the most promising marker for vascular inflammation.