EFFECTS OF ESTROGEN AND PROGESTERONE ON AGE-RELATED-CHANGES IN ARTERIES OF POSTMENOPAUSAL WOMEN

1. Hormone replacement therapy (HRT) with oestrogen or oestrogen plus progestin may have different effects on arterial structure and functio n, To examine this question, carotid artery intima-medial thickness (I MT) and indices of systemic and carotid arterial compliance were measu red in groups of older men, postmenopausal women not on HRT (non-HRT) and those women on long-term HRT with oestrogen alone (HRT-E) or oestr ogen plus progestin (HRT-EP). 2. Sixty men, 90 postmenopausal women ta king HRT and 91 not taking HRT participated in the study, The groups w ere similar for age, body mass index, numbers of smokers, physical act ivity, alcohol intake and blood pressure. 3. Plasma total cholesterol was reduced and high-density lipoprotein-cholesterol was increased in the HRT group compared with the non-HRT group; low-density lipoprotein -cholesterol, triglyceride and lipoprotein (a) values were similar in these two groups, Results for HRT-E and HRT-EP subgroups were similar, 4. Carotid TMT was significantly reduced in the HRT group compared wi th men and non-HRT groups, Results for HRT-E and HRT-EP subgroups were similar, 5. Mean systemic arterial compliance (SAG) was significantly greater in men than in women and was related to age; SAC was higher i n both HRT-E and HRT-EP groups compared with the non-HRT group, Indice s of carotid stiffness were similar in men and in non-HRT groups, The HRT-EP group showed increased carotid stiffness compared with the HRT- E group, 6. There is an apparent protective effect of long-term oestro gen therapy on carotid IMT and age-related changes in arterial stiffne ss, Progestin does not alter the WIT effects but may adversely influen ce arterial stiffness.