An inflammation score is better associated with basal than stimulated surrogate indexes of insulin resistance.

ABSTRACT

Most studies describe the association between one particular inflammatory marker and insulin resistance (IR), features of the metabolic syndrome, or progression to type 2 diabetes. We aimed to build an Inflammation Score as a tool to measure IR-associated inflammatory activity and to evaluate the ability of different surrogate indexes of IR to reflect the inflammatory state. We studied 81 subjects, aged 47.7 +/- 12 yr with a body mass index of 28.3 +/- 4 kg/m(2). The Inflammation Score was composed of white blood cell count, erythrocyte sedimentation rate, C-reactive protein, and soluble fraction of TNF-alpha receptors 1 and 2. All the subjects underwent a frequently sampled iv glucose tolerance test, an oral glucose tolerance test, and surrogate indexes of IR were calculated. Each increase in the Inflammation Score was associated with a progressive increase in IR. We found significant differences across categories (0-1, 2, 3, and 4-5 points in the score) in age (P = 0.048), waist circumference (P = 0.015), body mass index (P = 0.013), blood pressure (P = 0.005), and uric acid (P = 0.031). The Inflammation Score was significantly associated with all but three of the surrogate IR indexes [2-h insulin glucose ratio, Gutt's insulin sensitivity (SI) index, and Avignon's 2-h SI index]. Surrogate indexes obtained from basal values showed a similar correlation with the Inflammation Score than the SI from frequently sampled iv glucose tolerance test. In summary, the Inflammation Score is a useful tool in the evaluation of IR-associated inflammatory activity. The surrogate indexes obtained using fasting glucose and insulin appear to better reflect this inflammatory state. Basal rather than stimulated indexes should be used in the evaluation of therapeutic measures aimed at modifying IR-associated inflammatory activity.