Carotid artery intima thickness and flow velocity after discontinuation of hormone replacement therapy in postmenopausal women: follow-up study.
OBJECTIVE
To investigate the effect of discontinuation of hormone replacement therapy on the intima thickness and blood flow velocity of the common carotid artery.


METHODS
The thickness of the left common carotid artery intima and maximal systolic blood velocity were measured by real-time and Doppler ultrasonography in 75 healthy postmenopausal women starting sequential combined hormone replacement therapy. The measurements were performed at the start and after 6 and 12 months of the therapy. Thirty two women decided to discontinue the therapy after 6 months, whereas 43 continued.


RESULTS
In the group that continued with the hormone replacement therapy, a significant decrease was recorded in the mean baseline values for carotid artery intima thickness and flow velocity at 6 months (0.35+0.11 vs 0.54+0.19 mm and 0.73+0.16 vs 0.87+0.19 m/s, respectively, p?0.001) and 12 months of follow-up (0.36+0.1 mm and 0.72+0.15 m/s vs baseline, respectively, p?0.001). In women who discontinued the therapy, there were significant deviations from the baseline values in the intima thickness (0.36+0.11 vs. 0.59+0.09 mm, p=0.010) and flow velocity (0.75+0.14 vs. 0.85+0.16 m/s, p?0.001) at 6 but not at 12 months of the follow-up (0.55+0.12 mm, and 0.85+0.17 m/s vs baseline; p=0.148 and p=0.965, respectively).


CONCLUSIONS
Decreased flow velocity and reduced intima thickness were directly related to blood vessel wall dilatation after estrogen component of hormone replacement therapy. Discontinuation of the hormone replacement therapy returned the flow velocity and intima thickness to their baseline values.
Vidović
I P
IP
Department of Obstetrics and Gynecology, Sisters of Mercy University Hospital, Vinogradska c. 29, 10000 Zagreb, Croatia. ivana.pentz.vidovic@hi.hinet.hr
Demarin
V
V
Grubisić
G
G
Kuna
K
K
Huzjan
A L
AL
D000368:Aged; D000704:Analysis of Variance; D001783:Blood Flow Velocity; D017536:Carotid Artery, Common / Q000000981:diagnostic imaging*; D005260:Female; D005500:Follow-Up Studies; D020249:Hormone Replacement Therapy; D006801:Humans; D008875:Middle Aged; D017698:Postmenopause / Q000187:drug effects / Q000502:physiology*; D011336:Probability; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D017539:Tunica Intima / Q000187:drug effects / Q000648:ultrastructure*; D018608:Ultrasonography, Doppler