Novel Adiponectin-Resistin Indices and Ratios Predict Increased Cardiovascular Risk in Patients with Type 2 Diabetes Mellitus.

Objectives: Adiponectin and resistin are adipokines involved in insulin resistance, glucometabolic control and adiposity. There is evidence that hypoadiponectinemia and hyperresistinemia are associated with cardiovascular disease. Whether the ratio of Adiponectin-Resistin (AR) and Insulin Resistance Adiponectin-Resistin (IRAR) indices can be used as non-invasive biomarker of cardiovascular disease needs more attention. Therefore, the aim of this study was to assess the relationships of AR and IRAR indices with adiposity, glucometabolic control and cardiovascular risk incurred by high-sensitivity C-reactive protein (hsCRP) in healthy subjects and patients with Type 2 Diabetes Mellitus.

Methods: This observational case control study was conducted in the Department of Physiology and Medicine, King Saud University, Riyadh. A total of 191 (control = 84 and diabetic = 107) subjects were recruited. Body composition was assessed by bioelectrical impendence analyzer (BIA). Fasting blood samples were analyzed for glucose, glycosylated hemoglobin (HbA1c), high-sensitivity C-reactive protein (hsCRP), lipid profile, adiponectin, and resistin levels. The AR and IRAR indices were determined by formulas.

Results: Serum adiponectin levels were significantly lower in diabetics compared to control (95.45 ± 39.27 ng/ml vs 146.64 ± 56.36 ng/ml, p < .001) while serum resistin was significantly higher in diabetic when compared to control (2.94 ± 1.30 ng/ml vs 2.40 ± 1.09 ng/ml, p = .003). Furthermore, AR and IRAR indices were significantly increased in diabetic subjects when compared to control (.82 ± .29 vs .48 ± .35, p < .001) and (.30 ± .10 vs .17 ± .12, p < .001) respectively. ROC analysis revealed that these indices predicted increased cardiovascular risk with area under the curve (AUC) for adiponectin = .717 ( p = .001), resistin = .635 ( p = .002), AR index = .740 ( p < .001), and IRAR index = .737 ( p < .001) respectively. AR index correlated positively with Triglycerides (r = .354, p < .01), hsCRP (r = .264, p < .01), HbA1c (r = .425, p < .01), fat mass (r = .164, p < .05), Waist/Hip Ratio (WHR) (r = .248, p < .01), and negatively with high density lipoprotein (r=-.327, p < .01). Furthermore, IRAR index more strongly correlated with Triglycerides (r = .409, p < .01), hsCRP (r = .268, p < .01), HbA1c (r = .508, p < .01), fat mass (r = .152, p < .05), WHR (r = .256, p < .01), and negatively with high density lipoprotein (r = -.340, p < .01).

Conclusions: AR and IRAR indices correlate significantly with adiposity, glucometabolic control and cardiovascular risk in type 2 diabetic patients and non-diabetic individuals. They may prove to be useful integrated biomarkers to predict metabolic dysregulation and cardiovascular risk.