Abstract
Objectives
To determine if low dose conjugated equine estrogens (CEE) result in a reduction of
coronary artery atherosclerosis progression, and to relate these findings to previous
studies using the traditional dose.
Methods
Adult female monkeys (Macaca fascicularis) were fed an atherogenic diet for 10 months, to induce fatty streaks and small plaques
comparable to those present in early postmenopausal women, and then ovariectomized
and treated orally with: CEE (0.30 mg/day women's equivalent dose, n = 28) or placebo (n = 25) daily for 24 months. Body weight and estradiol were measured at 3, 6, 12 and 18
months and plasma lipids were measured at baseline and every 6 months.
Results
Despite the lack of effect on plasma lipid profiles, monkeys treated with low dose
CEE had marked reductions in coronary artery atherosclerosis plaque extent (intimal
area) in all three main coronary arteries: left anterior descending artery (52% less,
0.044 mm2 versus 0.091 mm2, p = 0.04); left circumflex artery (62% less, 0.045 mm2 versus 0.119 mm2, p = 0.006) and right circumflex artery (42% less, 0.018 mm2 versus 0.031 mm2, p = 0.20). The overall mean coronary atherosclerosis extent was 52% lower in CEE treated
animals (0.042 mm2 versus 0.088 mm2, p = 0.02).
Conclusion
Low dose CEE (0.30 mg/woman/day equivalent) was effective in reducing coronary atherosclerosis and the
magnitude of the protection was comparable to previously reported studies using doses
equivalent to 0.625 mg/woman/day. This study provides an experimental basis for the assumption that low
dose CEE may be as effective as the traditional dose in inhibiting coronary atherosclerosis
progression in early postmenopausal subjects.
Keywords
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Article info
Publication history
Accepted:
February 7,
2006
Received in revised form:
January 26,
2006
Received:
October 28,
2005
Identification
Copyright
© 2006 Elsevier Ireland Ltd. Published by Elsevier Inc. All rights reserved.
