Increased ferritin concentrations correlate with insulin resistance in female type 2 diabetic patients.
OBJECTIVE
Iron overload identified by elevated ferritin concentrations has been implicated in risks of altered glucose metabolism and diabetic complications. The relationship between ferritin and insulin resistance in different gender and ethnicities remains uncertain; this study aimed to investigate it using homeostasis model assessment (HOMA-IR), and to explore whether it is gender-specific.


METHODS
A total of 524 type 2 diabetic patients were selected cross-sectionally from a cohort participating in a diabetic control study in Taiwan.


RESULTS
Overall, tertiles of ferritin were significantly and dose-dependently associated with elevated fasting plasma glucose, hemoglobin A1c, high-sensitivity C-reactive protein, HOMA-IR levels as well as Western dietary pattern scores generated by factor analysis (all p trend <0.05). Stratified by gender, a 1-tertile ferritin increase significantly correlated with a 0.241-unit increase in HOMA-IR (beta = 0.241, p = 0.001) in female diabetes, but not in male diabetes (beta = 0.072, p = 0.232), after adjusting for demographic, dietary, clinical and inflammatory factors.


CONCLUSIONS
Iron overload, which produces elevated levels of ferritin, may augment insulin resistance in female but not in male type 2 diabetes. Longitudinal studies are warranted to establish relationships between iron stores and diabetes development in men and women of different ethnicities.
Department of Gastroenterology, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan, RO China.
Fung-Jung
FJ
Yu
Meng-Chuan
MC
Huang
Wen-Tsan
WT
Chang
Hsin-Fang
HF
Chung
Chin-Yi
CY
Wu
Shyi-Jang
SJ
Shin
Chih-Cheng
CC
Hsu
D000328:Adult; D000368:Aged; D001786:Blood Glucose / Q000032:analysis; D002097:C-Reactive Protein / Q000378:metabolism; D003430:Cross-Sectional Studies; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000503:physiopathology*; D004032:Diet; D002149:Energy Intake; D005215:Fasting; D005247:Feeding Behavior; D005260:Female; D005293:Ferritins / Q000097:blood*; D005500:Follow-Up Studies; D006442:Glycated Hemoglobin / Q000032:analysis / Q000378:metabolism; D006801:Humans; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance; D019190:Iron Overload / Q000503:physiopathology*; D016014:Linear Models; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D012737:Sex Factors; D016037:Single-Blind Method; D011795:Surveys and Questionnaires; D013624:Taiwan
D001786:Blood Glucose; D002097:C-Reactive Protein; D005293:Ferritins; D006442:Glycated Hemoglobin; D007328:Insulin