Glycated hemoglobin levels are mostly dependent on nonglycemic parameters in 9398 Finnish men without diabetes.
BACKGROUND
Determinants of the variance in glycated hemoglobin (HbA1c) among individuals without type 2 diabetes remain largely unknown.


OBJECTIVE
We investigated the determinants of HbA1c, fasting plasma glucose, and 2-hour glucose in an oral glucose tolerance test and the associations of these glycemic markers with insulin sensitivity and insulin secretion in Finnish men without type 2 diabetes.


METHODS
The design and setting were the cross-sectional population-based Metabolic Syndrome in Men study including 10 197 Finnish men, aged 45-70 years, and randomly selected from the population register of Kuopio, Eastern Finland.


METHODS
Participants were a total of 9398 men without type 2 diabetes or with newly diagnosed type 2 diabetes at baseline (mean age 57 ± 7 y; body mass index 27.0 ± 4.0 kg/m(2), mean ± SD) in the Metabolic Syndrome in Men study cohort.


METHODS
The intervention included an oral glucose tolerance test.


METHODS
Glycemic and nonglycemic determinants of the variance in HbA1c among participants without type 2 diabetes and the association of HbA1c with insulin secretion and insulin sensitivity were measured.


RESULTS
Age, fasting plasma glucose, and high-sensitivity C-reactive protein were the strongest determinants of HbA1c, explaining 12% of the variance in HbA1c levels in participants without type 2 diabetes. Disposition index (insulin secretion) and the Matsuda insulin sensitivity index (insulin sensitivity) explained only less than 2% of the variance in HbA1c in the participants without type 2 diabetes.


CONCLUSIONS
The variance in HbA1c among men without type 2 diabetes was largely determined by nonglycemic factors and only weakly by impaired insulin sensitivity and insulin secretion.
Institute of Clinical Medicine (M.F., A.S., H.C., J.K., M.L.), Department of Internal Medicine, University of Eastern Finland, and Institute of Clinical Medicine (H.C., J.K., M.L.), Department of Internal Medicine, University of Eastern Finland, Kuopio, and Kuopio University Hospital, 70210 Kuopio, Finland; Department of Medicine (C.L., S.M.H.), University of Texas Health Science Center, San Antonio, Texas 78229.
Maria
M
Fizelova
Alena
A
Stančáková
Carlos
C
Lorenzo
Steven M
SM
Haffner
Henna
H
Cederberg
Johanna
J
Kuusisto
Markku
M
Laakso
D000367:Age Factors; D000368:Aged; D001786:Blood Glucose / Q000032:analysis*; D015992:Body Mass Index; D003430:Cross-Sectional Studies; D003924:Diabetes Mellitus, Type 2 / Q000097:blood*; D005387:Finland; D005951:Glucose Tolerance Test; D006442:Glycated Hemoglobin / Q000032:analysis*; D006801:Humans; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance; D008297:Male; D008875:Middle Aged
D001786:Blood Glucose; D006442:Glycated Hemoglobin; D007328:Insulin