Can clinical factors estimate insulin resistance in type 1 diabetes?

Abstract

An insulin resistance syndrome (IRS) score was developed based on clinical risk factors in adults with childhood-onset type 1 diabetes in the Epidemiology of Diabetes Complications (EDC) Study and was validated using euglycemic-hyperinsulinemic clamp studies. Hypertension, waist-to-hip ratio (WHR), triglyceride and HDL cholesterol levels, family history of type 2 diabetes, and glycemic control were risk factors used to define the score. A score of 1 (lowest likelihood IRS) to 3 (highest likelihood IRS) was assigned for each risk f a c t o r. Eligible subjects (n = 24) were recruited from the EDC cohort based on tertile of IRS score. Subjects received an overnight insulin infusion to normalize glucose levels, then underwent a 3-h euglycemic-hyperinsulinemic (60 mU · m -2 · min -1 ) clamp. Glucose disposal rate (GDR) was determined during the last 30 min of the clamp. The GDR differed significantly by IRS group (9.65 ± 2.99, 8.02 ± 1.39, and 5.68 ± 2.16 m g · k g -1 · m i n -1 , P < 0.01). The GDR was inversely correlated with the IRS score (r = -0.64, P < 0.01). Using linear regression, the combination of risk factors that yielded the highest adjusted r 2 value (0.57, P < 0.001) were WHR, hypertension, and HbA 1 . This study found that clinical risk factors can be used to identify subjects with type 1 diabetes who are insulin resistant, and it provides validation of a score based on clinical factors to determine the extent of insulin resistance in type 1 diabetes. This score will be applied to the entire EDC population in future studies to determine the effect of insulin resistance on complications. D i a b e t e s 4 9 :6 2 6-632, 2000

Diabetic nephropathy is associated with low-grade inflammation in Type 1 diabetic patients

“…Both increased concentrations of IL-6 and CRP were associated with decreased insulin sensitivity, calculated as an estimated glucose disposal rate (eGDR) using a modified formula of another study [15]. Such tients and IL-6 showed an increase in parallel with the renal engagement.…”

“…Serum creatinine was determined using a modified Jaffe reaction. As a measure of insulin sensitivity we calculated the estimated glucose disposal rate (eGDR) with an equation developed by another study [15] and modified for HbA 1c . To define the severity of renal disease in addition to AER we estimated GFR by an equation derived from the Modification of Diet in Renal Disease (MDRD) Study [16,17] and also by a known formula [18].…”

Increased levels of mannan-binding lectin in type 1 diabetic patients with incipient and overt nephropathy

“…Serum creatinine was determined using a modified Jaffé reaction. As a measure of insulin sensitivity we calculated the estimated glucose disposal rate (eGDR) using an equation developed by Williams et al [11], modified for HbA 1 c. To define the severity of renal disease in addition to AER we estimated GFR using the Cockroft-Gault formula [12]. CRP was measured by radioimmunoassay and IL-6 by high-sensitivity enzyme immunoassay as previously described [3].…”

Changes in glycaemic control and risk of coronary artery disease in type 1 diabetes mellitus: findings from the Pittsburgh Epidemiology of Diabetes Complications Study (EDC)

“…Hypertension was defined as BP≥140/ 90 mmHg or use of medication specifically to lower BP. Estimated glucose disposal rate (eGDR), a measure of insulin sensitivity, was calculated using a regression equation derived from hyperinsulinaemic-euglycaemic clamp studies using HbA 1 , waist to hip ratio (WHR) and hypertension [19]. Fasting blood samples were taken for analysis of lipids, lipoproteins, serum creatinine and glycosylated Hb.…”