Poster Presentation ANZOS-Breakthrough Discoveries Joint Annual Scientific Meeting 2018

Glycoprotein acetyls (GlycA) associate with BMI and co-morbidities in childhood obesity (#241)

Christoph CS Saner 1 2 , Brooke BH Harcourt 2 3 , Melissa MW Wake 2 3 , Markus MJ Juonala 2 4 , Kung-Ting KKT Kao 1 2 3 , Richard RS Saffery 1 2 3 , David DB Burgner 1 2 3 , Matthew MS Sabin 1 2 3
  1. Department of Endocrinology, Royal Children`s Hospital, Parkville, Victoria, Australia
  2. Murdoch Children's Research Institute, Parkville, Victoria, Australia
  3. Department of Paediatrics, The University of Melbourne, Parkville, Victoria, Australia
  4. Department of Medicine, University of Turku and Division of Medicine, Turku, Finland

Introduction
Childhood obesity is a pro-inflammatory state associated with metabolic and cardiovascular complications. In adults, glycoprotein acetyls (GlycA), a newly described inflammatory marker, is associated with cardiovascular disease and all-cause mortality, but there are few paediatric data. In a cohort of children attending a tertiary paediatric obesity clinic, we investigated the relationship between GlycA and obesity-related cardiometabolic co-morbidities.

Methods
Participants were enrolled in COBRA (Childhood Overweight BioRepository of Australia) between 2009-2017. Study site was at the Royal Children’s Hospital, Melbourne. Data collected included demographic (age and sex), anthropometric (weight, height, BMI, pubertal stage) and clinical (blood pressure) measures. An 8-hour fasted blood sample was collected for liver function (to assess for non-alcoholic fatty liver disease, NAFLD) and GlycA. An OGTT revealed the status for impaired glucose tolerance (IGT), insulin resistance (IR) and type 2 diabetes mellitus (T2DM). Hypertension (HTN) was determined according to current guidelines. GlycA was analyzed by NMR spectroscopy of serum. Binomial regression modeling, adjusted for age, sex, BMI and pubertal stage, assessed the relationship between GlycA and each of the dichotomized outcome variables (IGT, IR, T2DM, NAFLD and HTN).

Results
216 participants were included (52% females, mean age 11.9 years (SD±3.1), 35% post-pubertal). The mean value for BMI z-score was 2.49 (SD±0.24), and for GlycA 1.103mmol/l (SD±0.123). GlycA was associated with BMI (pearsons ρ=0.29; p<0.001). Comorbidity prevalences were: IGT:36%, IR:55%, T2DM:2%, sHTN:49%, dHTN:26%, NAFLD:38% and hyperlipidaemia:25%. In fully adjusted models, GlycA was associated with hyperlipidemia (p<0.0001), IR (p<0.05) and NAFLD (p<0.05), but not with IGT, systolic or diastolic HTN.

Conclusion
Increased GlycA, indicative of chronic inflammation, was associated with BMI and its co-morbidities in obese children. Longitudinal studies are warranted to define its role as a predictive biomarker for adverse obesity-related outcomes in childhood.