Association Between Inflammatory Markers and Progression to Kidney Dysfunction: Examining Different Assessment Windows in Patients With Type 1 Diabetes

Abstract

OBJECTIVE To determine whether biomarkers of inflammation and endothelial dysfunction are associated with the development of kidney dysfunction and the time frame of their association. RESEARCH DESIGN AND METHODS Biomarkers were measured at four time points during 28 years of treatment and follow-up in patients with type 1 diabetes in the Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications (DCCT/EDIC) cohort. In addition to traditional biomarkers of inflammation (C-reactive protein and fibrinogen), we measured interleukin-6 (IL-6) and soluble tumor necrosis factor receptors 1 and 2 (sTNFR-1/2), markers of endothelial dysfunction (soluble intracellular adhesion molecule-1, vascular cell adhesion molecule-1, and E-selectin [sE-selectin]), and fibrinolysis (total and active plasminogen activator inhibitor-1 [PAI-1]). Renal outcomes were defined as progression to incident chronic kidney disease (stage 3 or more severe) or macroalbuminuria (albumin excretion rate ≥300 mg/24 h). Prospective multivariate event-time analyses were used to determine the association of each biomarker with each subsequent event within prespecified intervals (3-year and 10-year windows). RESULTS Multivariate event-time models indicated that several markers of inflammation (sTNFR-1/2), endothelial dysfunction (sE-selectin), and clotting/fibrinolysis (fibrinogen and PAI-1) are significantly associated with subsequent development of kidney dysfunction. Although some markers showed variations in the associations between the follow-up windows examined, the results indicate that biomarkers (sTNFR-1/2, sE-selectin, PAI-1, and fibrinogen) are associated with progression to chronic kidney disease in both the 3-year and the 10-year windows. CONCLUSIONS Plasma markers of inflammation, endothelial dysfunction, and clotting/fibrinolysis are associated with progression to kidney dysfunction in type 1 diabetes during both short-term and long-term follow-up.