Bicuspid Aortic Valve is associated with increased arterial stiffness in adult women with Turner Syndrome
JE Ostberg1, AE Donald2, C Storry2, N Lloyd2, C McCarthy1, J Halcox2 & GS Conway1
Cardiovascular disease, which may be structural or ischaemic, is the major cause of morbidity and mortality for women with Turner Syndrome (TS). This study investigated arterial augmentation index (AI%) and pulse wave velocity (PWV) as measures of arterial stiffness in adults with TS. A more positive AI% and greater PWV indicate increased arterial stiffness.
66 women with TS and 8 normal women, median (range) ages 32.8 (19.2-56.0) and 31.3 (20.5-41.7) years, and median (range) heights 1.46 (1.33-1.60) and 1.57 (1.49-1.64) metres respectively, were assessed. AI% (measured at the right radial artery) and PWV (right carotid to right femoral arteries) were correlated with clinical parameters, plasma renin activity (PRA), lipids, karyotype and history of smoking, oestrogen and growth hormone use, and echocardiographic findings, including presence of a bicuspid aortic valve (BAV), found in 20% of the TS women. This study was approved by the UCLH/GOS Ethics Committees.
The higher AI% in TS (mean (SD) 23.6 (13.0)%) compared with controls (18.8 (12.2)%) did not achieve significance (p=0.33); AI% was highest in those TS women with a BAV (31.3 (10.5)% vs 21.5 (13.1)%, p<0.05). There was also a strong correlation between AI% and age (Spearman's rho=0.49, p<0.01), blood pressure (systolic r=0.45, p<0.01; diastolic r=0.53, p<0.01), height (r=0.49, p<0.01) and previous GH therapy (r=-0.29, p<0.05). PWV did not differ between TS and control women but was associated with age (r=0.25, p<0.05) and BP (systolic r=0.36, p<0.01; diastolic r=0.34, p<0.01). PRA, lipids, karyotype, oestrogen and smoking history were not associated with AI%/PWV.
Age and BAV are the strongest independent predictors of AI% in women with TS. These findings suggest that structural abnormalities (BAV) may be associated with arterial stiffness. BP is the most important modifiable risk factor and should be a treatment priority.