Oral Presentation Australasian Diabetes in Pregnancy Society Annual Scientific Meeting 2016

High ferritin concentrations are associated with inflammation and increased risk of gestational diabetes mellitus but offer no clinical value as a diagnostic test. (#26)

Amina Khambalia 1 , Katie Powell 1 2 , Natasha Nassar 1 , Aidan McElduff 3 , Vitomir Tasevski 2 , Jonathan Morris 1 , Christine L Roberts 1
  1. Kolling Institute of Medical Research, University of Sydney, Sydney, NSW, Australia
  2. Pathology North, NSW Health Pathology , Royal North Shore Hospital, Sydney, NSW, Australia
  3. Northern Sydney Endocrine Centre and the University of Sydney , Royal North Shore Hospital, Sydney, NSW, Australia

Background: High serum ferritin levels have been associated with gestational diabetes (GDM). Previous studies have been unable to determine whether high ferritin levels result from excess body iron or inflammation or ascertain the clinical relevance of high ferritin in identifying women with GDM.

Objectives: To determine whether high ferritin levels reflect excess body iron or inflammation and its clinical relevance for improved diagnosis of GDM.

Methods:  Women with archived first trimester serum samples (2007-2009) were linked to birth and hospital records for data on maternal characteristics and GDM diagnosis. Blood was analysed for iron biomarkers: ferritin, soluble transferrin receptor (sTfR) and hepcidin and inflammatory biomarkers: C-reactive protein (CRP) and interleukin-6 (IL-6).  Associations between iron and inflammatory biomarkers and GDM were assessed using multivariate logistic regression. Receiver operating curves (ROC) curves were used to evaluate biomarkers as a diagnostic test for GDM.

Results: Of 10, 844 women, 368 (3.4%) had GDM. Adjusted analyses found risk of GDM was associated with higher ferritin (adjusted odds ratio (AOR): 1.35; 95% CI: 1.16, 1.58) and CRP (AOR 1.29, 95% CI: 1.14, 1.46) but not sTfR (p=0.46), IL-6 (p=0.51) or hepcidin (p=0.09) concentrations.  Increased ferritin levels were associated with increased CRP, IL-6 and hepicidin levels and decreased sTfR levels (all tests p<0.0001). All biomarkers had poor diagnostic test accuracy (area under curve ranged from 0.51-0.60). 

Conclusions: High ferritin levels in early pregnancy are associated with inflammation and increased risk of GDM but add little clinical value in accurately discriminating between women with and without GDM.