1. Prediabetes in youths: mechanisms and biomarkers
Ram Weiss, MD, Nicola Santoro, MD, Cosimo Giannini, MD, Alfonso Galderisi, MD, Giuseppina Rosaria Umano, MD, Prof Sonia Caprio, MD 
The Lancet Child & Adolescent Health 
Volume 1, Issue 3, Pages (November 2017)
DOI: /S (17)
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2. Figure 1 Insulin secretion during a hyperglycaemic clamp
Compared with individuals with normal glucose tolerance, those with impaired glucose tolerance have reduced first-phase insulin secretion and preserved second-phase insulin secretion. Those with type 2 diabetes have defects in both first-phase and second-phase insulin secretion.
The Lancet Child & Adolescent Health 2017 1, DOI: ( /S (17) )
Copyright © 2017 Elsevier Ltd Terms and Conditions

3. Figure 2 The disposition index across glucose tolerance categories
Data are from youths (aged 8–21 years) followed up at the Yale Obesity-Diabetes Clinic, New Haven, CT, USA (unpublished). At any given degree of insulin sensitivity, obese youths with normal glucose tolerance (body-mass index [BMI] z score 2·24 [SD 0·61]) have greater insulin secretion than those with impaired glucose tolerance (BMI z score 2·38 [0·48]) and those with type 2 diabetes (BMI z score 2·37 [0·62]). Although less prominent in insulin-sensitive individuals, at lower levels of insulin sensitivity (ie, greater insulin resistance), these differences are substantial and insulin secretion is insufficient to maintain normal glucose metabolism.
The Lancet Child & Adolescent Health 2017 1, DOI: ( /S (17) )
Copyright © 2017 Elsevier Ltd Terms and Conditions

4. Figure 3 Interplay between fat-derived hormones and cytokines
An excess of visceral adipose tissue is linked to ectopic fat deposition and abnormal secretion of adipokines. Obese patients with high visceral to subcutaneous fat ratio have decreased adiponectin and leptin concentrations, despite equivalent body-mass index and body fat percentages. Lowered adiponectin concentrations are associated with increased ectopic fat deposition in skeletal muscle and liver. Decreased leptin concentrations are associated with lower insulin sensitivity.
The Lancet Child & Adolescent Health 2017 1, DOI: ( /S (17) )
Copyright © 2017 Elsevier Ltd Terms and Conditions