Inflammatory Markers Are Increased in Youth with Type 1 Diabetes: The SEARCH Case-Control Study

Abstract

Abstract Context: Increased inflammation may contribute to type 1 diabetes (T1D) complications. Objective: The objective of the study was to investigate the association of inflammation with obesity, hyperglycemia and dyslipidemia in youth with T1D. Design: This was a cross-sectional study of youth with and without T1D. Setting: The study was conducted in Colorado and South Carolina. Patients: SEARCH Case-Control participants with T1D [n = 553, mean age 15 yr (range 10–22), median duration 2.7 yr] and without diabetes [n = 215, mean age 15 yr (range 10–22)]. Intervention: This was an observational study. Main Outcome Measures: IL-6, high-sensitivity C-reactive protein (hsCRP), fibrinogen, and leptin were measured. Results: Inflammatory markers were evaluated by diabetes status, quartiles of glycated hemoglobin, and obesity using multiple linear regression analyses, adjusted for age, sex, study site, race/ethnicity, T1D duration, body mass index, and pubertal status. Compared with controls, youth with T1D had higher IL-6 and fibrinogen levels at all levels of glycemia and obesity, and hsCRP levels were significantly higher in youth with T1D in the top three quartiles of glycated hemoglobin (≥7.2%) and among normal-weight subjects. Leptin was lower in youth with poor glycemic control. Higher hsCRP and fibrinogen were correlated with higher total and LDL cholesterol, and apolipoprotein B in youth with T1D, whereas higher fibrinogen was correlated with higher LDL and apolipoprotein B in controls. Conclusions: T1D is characterized by excess inflammation, independent of adiposity and glycemic control. Even T1D youth in good glycemic control had higher levels of IL-6 and fibrinogen than controls. Elevated inflammatory markers were associated with an atherogenic lipid profile, which may contribute to accelerated atherosclerosis in youth with T1D.