Plasma adiponectin, IL-6, hsCRP, and TNF-α levels in subject with diabetic foot and their correlation with clinical variables in a North Indian tertiary care hospital

Abstract

Aim: Pro- and anti-inflammatory processes are crucial in different phases of wound healing and their disturbances interfere with tissue homeostasis after the manifestation of ulcers, leading to chronic non-healing wounds. However, data on the association between infl ammation and acute foot syndrome are scarce.

Materials and methods: Circulating levels of acute-phase reactants and cytokines were measured in diabetic patients with ulcer (n = 162) and without ulcer (n = 162) in a case control study.

Results: Of the patients, 85.1% had type 2 diabetes. Subjects with diabetic foot ulcer showed lower median plasma level of adiponectin [8.4 (7.1-9.2) ng/ml vs. 13.4 (12.1-14.2) ng/ml], and higher median plasma levels of interleukin-6 (IL-6) [32.5 (9.4-44.8) ng/ml vs. 6.7 (4.6-14.6) ng/ml], high-sensitivity C-reactive protein (hsCRP) [12.6 (11.2-13.6) mg/ml vs. 8.4 (7.1-9.2) mg/ml], and tumor necrosis factor-alpha (TNF-α) [99.4 (79.9-121.5) ng/ml vs. 4.9 (4.5-5.6) ng/ml]. A positive correlation was found between body mass index (BMI) (r = -0.088, P < 0.264) and retinopathy (r = 0.249, P < 0.001) for adiponectin. For IL-6, it was between grade of ulcer (r = 0.250, P < 0.001), BMI (r = -0.161, P < 0.04), low density lipoprotein-cholesterol (LDL-C) (r = -0.155, P < 0.049), triglycerides (r = -0.165, P < 0.035), retinopathy (r = -0.166, P < 0.035), nephropathy (r = -0.199, P < 0.011), and smoking (r = -0.164, P < 0.036). For hsCRP: grade of ulcer (r = 0.236, P < 0.002), BMI (r = -0.155, P < 0.048), LDL-C (r = -0.174, P < 0.026), triglycerides (r = -0.216, P < 0.005), retinopathy (r = -0.165, P < 0.037), nephropathy (r = -0.028, P < 0.007), and smoking (r = -0.164, P < 0.036), while total cholesterol (r = -0.209, P < 0.007) and neuropathy (r = 0.141, P < 0.072) for TNF-α.

Conclusions: This study demonstrates that diabetic subjects with various grades of diabetic foot ulcer showed a higher IL-6, hsCRP, TNF-α, and lower adiponectin plasma levels in comparison with diabetes without foot ulcer, independent of the concomitant infections. It would be interesting to fi nd out whether an activation of immune system precedes the development of foot ulcer and whether anti-infl ammatory therapies might be effective in improving the outcome in such patients.

Keywords: Correlation; India; diabetic foot ulcer; inflammatory marker.