| Autor: |
Kanat M, Winnier D, Norton L, Arar N, Jenkinson C, Defronzo RA, Abdul-Ghani MA, Kanat, Mustafa, Winnier, Diedre, Norton, Luke, Arar, Nazik, Jenkinson, Chris, Defronzo, Ralph A, Abdul-Ghani, Muhammad A |
| Zdroj: |
Diabetes Care; Apr2011, Vol. 34 Issue 4, p1006-1010, 5p |
| Abstrakt: |
Objective: The study objective was to assess the relationship between β-cell function and HbA(1c).Research Design and Methods: A total of 522 Mexican American subjects participated in this study. Each subject received a 75-g oral glucose tolerance test (OGTT) after a 10- to 12-h overnight fast. Insulin sensitivity was assessed with the Matsuda index. Insulin secretory rate was quantitated from deconvolution of the plasma C-peptide concentration. β-Cell function was assessed with the insulin secretion/insulin resistance (IS/IR) (disposition) index and was related to the level of HbA(1c).Results: At HbA(1c) levels <5.5%, both the Matsuda index of insulin sensitivity and IS/IR index were constant. However, as the HbA(1c) increased >5.5%, there was a precipitous decrease in both the Matsuda index and the IS/IR index. Subjects with HbA(1c) = 6.0-6.4% had a 44 and 74% decrease in the Matsuda index and the IS/IR index, respectively, compared with subjects with HbA(1c) <5.5% (P < 0.01 for both indices). Subjects with normal glucose tolerance and HbA(1c) <5.7% had β-cell function comparable to that of subjects with normal glucose tolerance with HbA(1c) = 5.7-6.4%. However, subjects with impaired fasting glucose or impaired glucose tolerance had a marked decrease in β-cell function independent of their HbA(1c) level.Conclusions: The results of the current study demonstrate that in Mexican Americans, as HbA(1c) increases >6.0%, both insulin sensitivity and β-cell function decrease markedly. Performing an OGTT is pivotal for accurate identification of subjects with impaired β-cell function. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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