Association of circulating cellular adhesion molecules with menopausal status and hormone replacement therapy - Time-dependent change in transdermal,but not oral estrogen users

The incidence of coronary heart disease is lower in premenopausal than in p ostmenopausal women, and estrogen use may be cardioprotective among postmen opausal women. Cellular adhesion molecules (CAM) are involved in the early stage of atherosclerosis, and short-term administration of oral estrogen de creased plasma concentrations of their soluble forms in postmenopausal wome n. However, data evaluating transdermal estrogen are sparse and long-term e ffect of hormone replacement therapy (HRT) on CAM is unknown. Therefore, we have investigated the association of circulating CAM (cCAM) with menopausa l status and long-term HRT. Plasma levels of intercellular adhesion molecul e-1 (cICAM-1), vascular cell adhesion molecule-1 (cVCAM-1), P-selectin, E-s electin, C-reactive protein (CRP), and fibrinogen were measured in 74 preme nopausal women, 60 postmenopausal women not using HRT, 30 postmenopausal wo men using opposed oral estrogen therapy, and 30 postmenopausal women using opposed transdermal estrogen therapy. All women were apparently healthy and aged between 45 and 54 years. Duration of HRT ranged from 3 to 96 months. Postmenopausal women not receiving HRT had 24% higher mean levels of cICAM- 1 than premenopausal women (318 vs. 255 ng/ mi, P<.001). In postmenopausal women, users of oral estrogen had 16% lower, and users of transdermal estro gen had 17% lower mean levels of cICAM-1 than non-users (268 and 264 vs. 31 8 ng/ml, P=.001 for both comparisons). Furthermore, in users of transdermal route, the lowering effect of estrogen on cICAM-1 was dependent on treatme nt duration, while no time-dependent effect was seen in oral estrogen users . Users of transdermal estrogen had lower cVCAM-1 and P-selectin levels tha n postmenopausal non-users (327 vs. 364 ng/ml (P=.05) and 18 vs. 23 ng/ml ( P=.05). There was no difference in CRP and E-selectin levels between the gr oups. Adjustment for age and body mass index (BMI) made no substantial chan ge in the results. These data suggest that oral and transdermal estrogen ma y play a long-term cardioprotective role through favourable changes in endo thelial function. (C) 2001 Elsevier Science Ltd. All rights reserved.