Androgenicity and venous endothelial function in post-menopausal women.
BACKGROUND
Endothelial dysfunction is one of the early signs of cardiovascular damage. High androgen levels have been related to inflammatory endothelial markers in pre- and post-menopausal women.


OBJECTIVE
This cross-sectional study aimed at investigating whether free androgen index (FAI) [estimated by dividing total testosterone (nmol/l) by SHBG (nmol/l) x 100] is related to endothelial function during post-menopause.


METHODS
Twenty-six post-menopausal women were assessed with the dorsal hand vein compliance technique. Acetylcholine (Ach) and sodium nitroprusside (SNP) dose-response curves were constructed to test endothelium-dependent and independent relaxation, respectively.


RESULTS
Mean age was 54 yr (+/-4) and median time since menopause was 6 yr (interquartile range: 3-9). Patients were stratified according to FAI levels into two groups: FAI greater than or less than the group median of 2.5. Waist-to-hip ratio (WHR) was significantly higher in the group with FAI>2.5, as well as median dose of Ach for maximal vasodilation [720 (360-3600) ng/min with FAI>2.5 vs 36 (0.36-360) ng/min with FAI<or=2.5; p=0.005]. Maximal vasodilation with SNP was similar in both groups. Positive correlations were observed between Ach doses and maximal vasodilation and FAI (r=0.473, p=0.015), waist (r=0.510, p= 0.011), and WHR (r=0.479, p=0.021). SHBG was negatively correlated with Ach doses (rs=-0.400, p=0.043).


CONCLUSIONS
This study suggests that FAI, even within normal limits, is related to early changes in endothelial function in healthy post-menopausal women. Longitudinal studies are required to determine the clinical relevance of these findings.
Maturana
M A
MA
Gynecological Endocrinology Unit, Division of Endocrinology, Hospital de Clinicas of Porto Alegre, CEP 90035-003, Porto Alegre, RS, Brazil.
Rubira
M C
MC
Consolim-Colombo
F
F
Irigoyen
M C
MC
Spritzer
P M
PM
D000109:Acetylcholine / Q000494:pharmacology; D000728:Androgens / Q000097:blood*; D015992:Body Mass Index; D003430:Cross-Sectional Studies; D004730:Endothelium, Vascular / Q000502:physiology* / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009599:Nitroprusside / Q000494:pharmacology; D017698:Postmenopause / Q000502:physiology*; D014665:Vasodilator Agents / Q000494:pharmacology; D014680:Veins / Q000033:anatomy & histology* / Q000187:drug effects / Q000502:physiology*; D049629:Waist-Hip Ratio
D000728:Androgens; D014665:Vasodilator Agents; D009599:Nitroprusside; D000109:Acetylcholine