ESPE Abstracts (2014) 82 P-D-1-1-199

Associations of Vascular Biomarkers and the Somatotrophic Axis with Carotid Ultrasound and Echocardiography Findings in Relation to Turner Arteriopathy

Ahmet Uçara, Fahrettin Özb, Firdevs Başa, Hüseyin Oflazb, Kemal Nişlic, Melike Tuğrula, Feyza Darendelilera, Nurçin Sakaa, Şükran Poyrazoğlua & Rüveyde Bundaka

aPediatric Endocrine Unit, Istanbul Medical Faculty, Istanbul University, Istanbul, Turkey; bDepartment of Cardiology, Istanbul Medical Faculty, Istanbul University, Istanbul, Turkey; cPediatric Cardiology Unit, Istanbul Medical Faculty, Istanbul University, Istanbul, Turkey

Background: Turner syndrome (TS) is associated with increased arterial stiffness. To date, factors associated with the ontogeny of Turner arteriopathy remain unclear.

Objective and hypotheses: To assess the associations of vascular biomarkers and the somatotrophic axis with arterial stiffness indices, and left heart size, in normotensive ‘dipper’ TS.

Method: Sixty-one patients with uncomplicated normotentensive ‘dipper’ TSwith a mean age of 12.6 years (range 6.6–27.3 years) and body surface area (BSA) of 34 matched with healthy peers were compared using carotid ultrasound and echocardiography. We derived several arterial stiffness and left heart size indices in association with vascular biomarkers (high sensitivity C-reactive protein (hsCRP), B-type natriuretic peptide (BNP), Atrial NP (ANP), aldosterone/plasma renin activity (PRA)), IGF1 and IGF-binding protein 3 after correcting for metabolic syndrome antecedents such as obesity, insulin resistance (IR), dyslipidemia, and hypertension.

Results: TS patients had higher BMI and waist circumference than controls. The frequencies of dyslipidemia and homeostasis model assessment-insulin resistance were similar in both groups. The TS patients had higher hsCRP, BNP, and ANP levels than controls. Plasma aldosterone/PRA ratios, IGF1 and IGFBP3 were similar in both groups. The carotid intima media thickness (cIMT) SDS, β-index SDS, incremental modulus of elasticity (Einc) SDS, BSA corrected left ventricle mass (LVM) and left atrial volume (LAV) were higher, and the distensibility coefficient (DC) SDS was lower in TS than in controls. Multivariable regression analyses revealed that BNP was associated with cIMT SDS (β=0.17, P<0.01), β-index SDS (β=0.62, P<0.01), EincSDS (β=0.39, P=0.01) and DC SDS (β=−0.53, P<0.01). IGF1 SDS was associated with cIMT SDS (β=0.81, P<0.01), β-index SDS (β=0.17, P<0.01). hs-CRP was associated with DC SDS (β=−0.16, P<0.01). LVM and LAV were not associated with biomarkers and IGF1 after correction for multiple testing. When the whole cohort was evaluated, TS was independently associated with increased arterial stiffness indices and LVM (β=0.420–3.424, P<0.001 for all, R2=0.06–0.31).

Conclusions: Normotensive TS ‘dippers’ have increased arterial stiffness when compared with healthy controls. BNP, and to a variable extent, IGF1 and hsCRP are associated with arterial stiffness indices in TS. Further research is needed to clarify the causal inference of these relationships.