Objective: Women with Turner syndrome (TS) face increased morbidity and mortality from congenital and acquired cardiovascular (CV) diseases. Traditional indices of unfavourable CV risk are increased in TS. However, the single most common syndrome-related feature remains estrogen deficiency. The present trial therefore aimed to investigate total CV risk in TS as expressed by ambulatory arterial stiffness index (AASI) and the influence of female sex hormone replacement therapy (HRT).

Design and Methods: Randomly recruited women with TS receiving HRT (n=26) were examined following wash-out and during 6 months of HRT in the form of cyclical estrogen and progestin. Age-matched normally menstruating female controls (n=24) were examined once. Parameters of effect were 24-hour ambulatory blood pressures, AASI in addition to various metabolic and anthropometric indices of CV risk.

Results: Besides being takykardic TS women displayed relative systolic and diastolic hypertension with diminished circadian variation, while pulse pressures were similar. HRT in TS brought on a significant fall in diastolic pressures and borderline significant reduction in diurnal pulse variability. AASI was significantly elevated in TS prior to HRT when compared to controls (T_b vs. C: 0.36 (0.02) vs. 0.26 (0.03), P=0.01) and unaffected by HRT. Individual status, i.e. being TS or not, was the major explanatory variable to AASI followed by age, insulin sensitivity and the degree of diurnal pulse variability.

Conclusion: AASI was elevated in TS following HRT wash-out which possibly indicated a syndrome-associated elevated CV risk with no direct impact of HRT during 6 months.