Francesca Olivieri1, Chiara Zusi1, Anita Morandi1, Massimiliano Corradi1, Maria L Boselli2, Elena Fornari1, Riccardo C Bonadonna3,4, Claudio Maffeis5. 1. Pediatric Diabetes and Metabolic Disorders Unit, University Hospital of Verona, Verona, Italy. 2. Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, University Hospital of Verona, Verona, Italy. 3. Department of Medicine and Surgery, University of Parma, Parma, Italy. 4. Division of Endocrinology and Metabolic Diseases, Azienda Ospedaliero-Universitaria di Parma, Parma, Italy. 5. Pediatric Diabetes and Metabolic Disorders Unit, University Hospital of Verona, Verona, Italy. claudio.maffeis@univr.it.
Abstract
OBJECTIVE: To assess whether combining glucose shape and 2-h glucose concentration during an oral glucose tolerance test (OGTT) may help identifying normal glucose tolerant obese children/adolescents with an impaired glucose tolerant (IGT)-like metabolic profile in term of insulin sensitivity (Matsuda index) and β-cell function (disposition index: DI). SUBJECTS, METHODS, AND MAIN OUTCOME MEASURE: In total, 654 non-diabetic obese children/adolescents underwent a 2 h OGTT. The whole population was classified according to 2-hour plasma glucose ( < 100, 100-119, 120-139, 140-200 mg/dL) and glucose shape (monophasic or biphasic). Monophasic morphology was characterized by an increase in OGTT glucose concentration followed by a decline of at least 4.5 mg/dL, a biphasic response was defined as a decrease in glucose after an initial increase, followed by a second increase of ≥ 4.5 mg/dL. A subset of 69 participants had also a prolonged OGTT to estimate β-cell function in "biphasic" versus "monophasic" patients. RESULTS: Matsuda index and DI decreased across 2-h glucose categories (both p < 0.001) and were lower in monophasic compared with biphasic children, independently of 2-h glucose category (both p < 0.001, both p for glucose category×shape interaction > 0.05). Normal glucose tolerant children with 2-h glucose of 120-139 mg/dl and monophasic glucose shape did not differ from IGT children, as regards Matsuda index and DI (both p > 0.05). Among children undergoing a prolonged OGTT, those with a monophasic glucose shape had worse β-cell function, modeled as proportional control, than those with a biphasic shape (p = 0.031). CONCLUSIONS: A monophasic OGTT glucose shape is associated with unfavorable glucose metabolism independently of 2-h glucose concentration. Children combining monophasic shape and normal-high 2-h glucose have an IGT-like glucose metabolism.
OBJECTIVE: To assess whether combining glucose shape and 2-h glucose concentration during an oral glucose tolerance test (OGTT) may help identifying normal glucose tolerant obesechildren/adolescents with an impaired glucose tolerant (IGT)-like metabolic profile in term of insulin sensitivity (Matsuda index) and β-cell function (disposition index: DI). SUBJECTS, METHODS, AND MAIN OUTCOME MEASURE: In total, 654 non-diabetic obesechildren/adolescents underwent a 2 h OGTT. The whole population was classified according to 2-hour plasma glucose ( < 100, 100-119, 120-139, 140-200 mg/dL) and glucose shape (monophasic or biphasic). Monophasic morphology was characterized by an increase in OGTT glucose concentration followed by a decline of at least 4.5 mg/dL, a biphasic response was defined as a decrease in glucose after an initial increase, followed by a second increase of ≥ 4.5 mg/dL. A subset of 69 participants had also a prolonged OGTT to estimate β-cell function in "biphasic" versus "monophasic" patients. RESULTS: Matsuda index and DI decreased across 2-h glucose categories (both p < 0.001) and were lower in monophasic compared with biphasic children, independently of 2-h glucose category (both p < 0.001, both p for glucose category×shape interaction > 0.05). Normal glucose tolerant children with 2-h glucose of 120-139 mg/dl and monophasic glucose shape did not differ from IGT children, as regards Matsuda index and DI (both p > 0.05). Among children undergoing a prolonged OGTT, those with a monophasic glucose shape had worse β-cell function, modeled as proportional control, than those with a biphasic shape (p = 0.031). CONCLUSIONS: A monophasic OGTT glucose shape is associated with unfavorable glucose metabolism independently of 2-h glucose concentration. Children combining monophasic shape and normal-high 2-h glucose have an IGT-like glucose metabolism.