Glycemic variability predicts inflammation in adolescents with type 1 diabetes

Background: Adolescents with type 1 diabetes (T1D) have increased risk of cardiovascular disease as well as elevations in biomarkers of systemic inflammation, plasma protein oxidation and vascular endothelial injury. It is unclear whether hyperglycemia itself, or variations in blood glucose are predictors of these abnormalities. Methods: This study was designed to determine the relationship of inflammatory (C-reactive protein, CRP), oxidative (total anti-oxidative capacity, TAOC) and endothelial injury (soluble intracellular adhesion molecule 1, sICAM1) markers to glycemic control measures from 3 days of continuous glucose monitoring (CGM) and to hemoglobin A(1c) (HbA(1c)), and HbA(1c) x duration area under the curve (A1cDur). Results: Seventeen adolescents (8 F/9M; age, 13.1 +/- 1.6 years (mean +/- SD); duration, 4.8 +/- 3.8 years, BMI, 20.3 +/- 3.1 kg/m(2); A1c, 8.3 +/- 1.2%) were studied. Log CRP but was not related to age, duration, body mass index (BMI), HbA(1c), or A1cDUR. TAOC increased as logA1cDUR increased (n = 13, r = 0.61, p = 0.028). CRP and sICAM were not related to CGM average glucose but log CRP increased as 3 day glucose standard deviation increased (r = 0.66, p = 0.006). TAOC increased as glucose standard deviation increased (r = 0.63, p = 0.028). Conclusions: Increased glucose variability is associated with increased inflammation in adolescents withT1D. Increased TAOC with increasing variability may be an effort to compensate for the ongoing oxidative stress.