title: Factors Associated with Higher Pro-Inflammatory Tumor Necrosis Factor-α Levels in Young Women with Type 1 Diabetes.
abstract: OBJECTIVE
  While cytokines play a role in the etiology of type 1 diabetes, cytokines later in the disease are less understood. We therefore investigated associations of pro-inflammatory tumor necrosis factor-α levels measured at prolonged disease duration with C-peptide at diagnosis, long-term glycemic control, diabetes duration, clinical factors, and health behaviors.
  
  
  METHODS
  Data and blood were collected during an ancillary study to the longitudinal Wisconsin Diabetes Registry, a population-based cohort followed since diagnosis of type 1 diabetes. The ancillary study was conducted at 13-18 years diabetes duration, and enrolled premenopausal women age 18-45 years (n=87).
  
  
  RESULTS
  Higher tumor necrosis factor-α levels at 13-18 years diabetes duration were independently associated with longer duration (p=0.0004) and worse current renal function (p=0.02). Additionally, diabetes duration modified both of the positive associations of tumor necrosis factor-α levels (both interactions p≤0.01) with mean glycemic control during the previous 10 years (significant only in women with longer durations) and current daily caffeine intake (significant only in women with shorter durations). In women with C-peptide measured at diagnosis (n=50), higher tumor necrosis factor-α levels at 13-18 years duration were associated with lower C-peptide (p=0.01), independent of glycemic control during the previous 10 years.
  
  
  CONCLUSIONS
  Lower residual C-peptide at diagnosis and poor long-term glycemic control independently predicted higher pro-inflammatory tumor necrosis factor-α levels years later. The novel relationship with C-peptide needs confirmation in a larger cohort. Given the association between tumor necrosis factor-α and diabetes complications, further longitudinal studies may help clarify the potentially complex associations between glycemic control, inflammatory cytokines, and complications.
authors.affiliation: Division of Transplant Surgery, College of Medicine, University of Illinois at Chicago.
authors.forename: K K
authors.initials: KK
authors.lastname: Danielson
authors.affiliation: Division of Transplant Surgery, College of Medicine, University of Illinois at Chicago.
authors.forename: R S
authors.initials: RS
authors.lastname: Monson
authors.affiliation: Department of Population Health Sciences, University of Wisconsin-Madison.
authors.forename: T J
authors.initials: TJ
authors.lastname: LeCaire
mesh_terms: D000293:Adolescent; D000328:Adult; D002096:C-Peptide / Q000097:blood*; D003922:Diabetes Mellitus, Type 1 / Q000097:blood*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008875:Middle Aged; D012042:Registries; D013997:Time Factors; D014409:Tumor Necrosis Factor-alpha / Q000097:blood*
chemical_list: D002096:C-Peptide; D014409:Tumor Necrosis Factor-alpha