Mandy Ho1, Megan Gow, Louise A Baur, Paul Z Benitez-Aguirre, Charmaine S Tam, Kim C Donaghue, Maria E Craig, Chris T Cowell, Sarah P Garnett. 1. Discipline of Pediatrics and Child Health (M.H., M.G., L.A.B., K.C.D., M.E.C., C.T.C., S.P.G.), The Children's Hospital at Westmead Clinical School, University of Sydney, Westmead, NSW 2145, Australia; Institute of Endocrinology and Diabetes (M.H., M.G., P.Z.B.-A., K.C.D., M.E.C., C.T.C., S.P.G.), and Kids Research Institute (L.A.B., C.T.C.), The Children's Hospital at Westmead, Westmead, NSW 2145, Australia; The Charles Perkins Centre and School of Biological Sciences (C.S.T.), University of Sydney, Camperdown, NSW 2006, Australia; Department of Endocrinology (C.S.T.), Royal Prince Alfred Hospital, Camperdown, NSW 2006, Australia; and School of Women and Children's Health (M.E.C.), University of New South Wales, Randwick, NSW 2031, Australia.
Abstract
CONTEXT: Reduced arterial elasticity contributes to an obesity-related increase in cardiovascular risk in adults. OBJECTIVE: To evaluate the effect of fat loss on arterial elasticity in obese adolescents at risk of type 2 diabetes. DESIGN: A secondary data analysis of the RESIST study was performed in two hospitals in Sydney, Australia. PARTICIPANTS: The study included 56 subjects (ages, 10 to 17 y; 25 males) with prediabetes and/or clinical features of insulin resistance. INTERVENTION: A 12-month lifestyle plus metformin intervention. OUTCOMES: Arterial elasticity and systemic vascular resistance were measured using radial tonometry pulse contour analysis, percentage body fat (%BF) was measured by dual-energy x-ray absorptiometry, and insulin sensitivity index was derived from an oral glucose tolerance test and lipids. RESULTS: Adolescents (n = 31) with decreased %BF (mean change [range], -4.4% [-18.3 to -0.01%]) after the intervention had significant increases in the mean large arterial elasticity index (mean change [95%CI], 5.1 [1.9 to 8.2] mL/mm Hg * 10; P = .003) and insulin sensitivity index (0.5 [0.1 to 0.9]; P = .010) and a decrease in systemic vascular resistance (-82 [-129 to -35] dyne * s * cm(-5); P = .001). There were no significant changes in these parameters in adolescents who increased their %BF. Nor was there any significant change in the mean small arterial elasticity index in either group. CONCLUSION: Long-term follow-up of these adolescents is warranted to assess whether the observed changes in vascular elasticity will lead to a clinical benefit including reduced cardiovascular morbidity and mortality.
RCT Entities:
CONTEXT: Reduced arterial elasticity contributes to an obesity-related increase in cardiovascular risk in adults. OBJECTIVE: To evaluate the effect of fat loss on arterial elasticity in obese adolescents at risk of type 2 diabetes. DESIGN: A secondary data analysis of the RESIST study was performed in two hospitals in Sydney, Australia. PARTICIPANTS: The study included 56 subjects (ages, 10 to 17 y; 25 males) with prediabetes and/or clinical features of insulin resistance. INTERVENTION: A 12-month lifestyle plus metformin intervention. OUTCOMES: Arterial elasticity and systemic vascular resistance were measured using radial tonometry pulse contour analysis, percentage body fat (%BF) was measured by dual-energy x-ray absorptiometry, and insulin sensitivity index was derived from an oral glucose tolerance test and lipids. RESULTS: Adolescents (n = 31) with decreased %BF (mean change [range], -4.4% [-18.3 to -0.01%]) after the intervention had significant increases in the mean large arterial elasticity index (mean change [95%CI], 5.1 [1.9 to 8.2] mL/mm Hg * 10; P = .003) and insulin sensitivity index (0.5 [0.1 to 0.9]; P = .010) and a decrease in systemic vascular resistance (-82 [-129 to -35] dyne * s * cm(-5); P = .001). There were no significant changes in these parameters in adolescents who increased their %BF. Nor was there any significant change in the mean small arterial elasticity index in either group. CONCLUSION: Long-term follow-up of these adolescents is warranted to assess whether the observed changes in vascular elasticity will lead to a clinical benefit including reduced cardiovascular morbidity and mortality.