TY - JOUR

T1 - Dynamic assessment of insulin secretion and insulin resistance in Asians with prediabetes

AU - Magkos, Faidon

AU - Lee, Michelle H

AU - Lim, Maybritte

AU - Cook, Alex R

AU - Chhay, Vanna

AU - Loh, Tze Ping

AU - Chia, Kee Seng

AU - Baig, Sonia

AU - Ang, Ian Yi Han

AU - Tay, Joanne Y Y

AU - Khoo, Chin Meng

AU - Halter, Jeffrey B

AU - Toh, Sue-Anne

N1 - Copyright © 2021. Published by Elsevier Inc.

PY - 2022

Y1 - 2022

N2 - Aims/hypothesis: Prediabetes and type 2 diabetes are highly prevalent in Asia. Understanding the pathophysiology of abnormal glucose homeostasis in Asians will have important implications for reducing disease burden, but there have been conflicting reports on the relative contributions of insulin secretion and action in disease progression. In this study, we aimed to assess the contribution of β-cell dysfunction and insulin resistance in the Asian prediabetes phenotype.Methods: We recruited 1679 Asians with prediabetes (n = 659) or normoglycemia (n = 1020) from a multi-ethnic population in Singapore. Participants underwent an oral glucose tolerance test, an intravenous glucose challenge, and a hyperinsulinemic-euglycemic clamp procedure to determine glucose tolerance, β-cell responsivity, insulin secretion, insulin clearance and insulin sensitivity.Results: Participants with prediabetes had significantly higher glucose concentrations in the fasting state and after glucose ingestion than did normoglycemic participants. Insulin sensitivity (M/I ratio) was ~15% lower, acute insulin response (AIR) to intravenous glucose and β-cell responsivity to oral glucose were ~35% lower, but total insulin secretion rate in the fasting state and after glucose ingestion was ~10% greater in prediabetic than in normoglycemic participants. The decrease in β-cell function with worsening glucose homeostasis in Asians with prediabetes was associated with progressively greater defects in AIR rather than M/I. However, analysis using static surrogate measures (HOMA indices) of insulin resistance and β-cell function revealed a different pattern.Conclusions: Lower AIR to intravenous glucose and β-cell responsivity to oral glucose, on a background of mild insulin resistance, are the major contributors to the dysregulation of glucose homeostasis in Asians with prediabetes.

AB - Aims/hypothesis: Prediabetes and type 2 diabetes are highly prevalent in Asia. Understanding the pathophysiology of abnormal glucose homeostasis in Asians will have important implications for reducing disease burden, but there have been conflicting reports on the relative contributions of insulin secretion and action in disease progression. In this study, we aimed to assess the contribution of β-cell dysfunction and insulin resistance in the Asian prediabetes phenotype.Methods: We recruited 1679 Asians with prediabetes (n = 659) or normoglycemia (n = 1020) from a multi-ethnic population in Singapore. Participants underwent an oral glucose tolerance test, an intravenous glucose challenge, and a hyperinsulinemic-euglycemic clamp procedure to determine glucose tolerance, β-cell responsivity, insulin secretion, insulin clearance and insulin sensitivity.Results: Participants with prediabetes had significantly higher glucose concentrations in the fasting state and after glucose ingestion than did normoglycemic participants. Insulin sensitivity (M/I ratio) was ~15% lower, acute insulin response (AIR) to intravenous glucose and β-cell responsivity to oral glucose were ~35% lower, but total insulin secretion rate in the fasting state and after glucose ingestion was ~10% greater in prediabetic than in normoglycemic participants. The decrease in β-cell function with worsening glucose homeostasis in Asians with prediabetes was associated with progressively greater defects in AIR rather than M/I. However, analysis using static surrogate measures (HOMA indices) of insulin resistance and β-cell function revealed a different pattern.Conclusions: Lower AIR to intravenous glucose and β-cell responsivity to oral glucose, on a background of mild insulin resistance, are the major contributors to the dysregulation of glucose homeostasis in Asians with prediabetes.

KW - Faculty of Science

KW - Asian prediabetes

KW - Insulin secretion

KW - Insulin sensitivity

KW - Hyperinsulinemic-euglycemic clamp

KW - Acute insulin response

KW - Oral glucose minimal modeling

U2 - 10.1016/j.metabol.2021.154957

DO - 10.1016/j.metabol.2021.154957

M3 - Journal article

C2 - 34942192

VL - 128

JO - Metabolism

JF - Metabolism

SN - 0026-0495

M1 - 154957

ER -