Changes in pituitary-ovarian hormones across the menopausal transition have multiple physiological consequences. However, little is known about how the major types of postmenopausal hormone therapy (HT) affect pituitary-ovarian hormonal relationships. This study evaluated these relationships in recently menopausal women (52.45 ± 2.49 yr of age) in the Kronos Early Estrogen Prevention Study (KEEPS) who were compliant to randomized, double-blinded treatment with oral conjugated equine estrogen (o-CEE; n = 109), transdermal 17β-estradiol (t-E2; n = 107), or placebo ( n = 146). Androstenedione, testosterone, 17β-estradiol, estrone, follicle-stimulating hormone (FSH), and luteinizing hormone (LH) were measured in serum before (baseline) and 48 mo after randomization to treatment. Descriptive summaries of hormone levels were performed, and multiple regression analyses were used to examine the effects of o-CEE, t-E2, and placebo on these hormone levels at 48 mo, adjusting for baseline levels. A network analysis examined the covariance of changes in hormone levels over the 48 mo within treatment groups. As expected, at 48 mo of treatment, hormone levels differed between women in the two active treatment groups compared with placebo, and network analysis indicated stronger relationships among hormone levels in the t-E2 and o-CEE groups compared with placebo. Associations among testosterone, 17β-estradiol, FSH, and LH differed between the o-CEE group compared with t-E2 and placebo groups. Thus, two common HT regimens differentially alter pituitary-ovarian hormone levels, altering feedback cycles and interhormonal associations in recently menopausal women. These interactions provide the basis for future studies investigating the impact of hormonal modulation of aging, including cognitive decline in women.
The Kronos Early Estrogen Prevention Study (KEEPS): what have we learned?
Abstract Objective: The Kronos Early Estrogen Prevention Study (KEEPS) was designed to address gaps in understanding the effects of timely menopausal hormone treatments (HT) on cardiovascular health and other effects of menopause after the premature termination of the Women's Health Initiative. Method: The KEEPS was a randomized, double-blinded, placebo-controlled trial to test the hypothesis that initiation of HT (oral conjugated equine estrogens [o-CEE] or transdermal 17β-estradiol [t-E 2 ]) in healthy, recently postmenopausal women ( n = 727) would slow the progression of atherosclerosis as measured by changes in carotid artery intima-media thickness (CIMT). Results: After 4 years, neither HT affected the rate of increase in CIMT. There was a trend for reduced accumulation of coronary artery calcium with o-CEE. There were no severe adverse effects, including venous thrombosis. Several ancillary studies demonstrated a positive effect on mood with o-CEE, and reduced hot flashes, improved sleep, and maintenance of bone mineral density with both treatments. Sexual function improved with t-E 2 . There were no significant effects of either treatment on cognition, breast pain, or skin wrinkling. Variants of genes associated with estrogen metabolism influenced the age of menopause and variability in effects of the HT on CIMT. Platelet activation associated with the development of white matter hyperintensities in the brain. Conclusions: KEEPS and its ancillary studies have supported the value and safety of the use of HT in recently postmenopausal women and provide a perspective for future research to optimize HT and health of postmenopausal women. The KEEPS continuation study continues to pursue these issues.
Effects of Oral vs Transdermal Estrogen Therapy on Sexual Function in Early Postmenopause
Effects of oral versus transdermal menopausal hormone treatments on self-reported sleep domains and their association with vasomotor symptoms in recently menopausal women enrolled in the Kronos Early Estrogen Prevention Study (KEEPS)
Abstract Objective: This study determined whether two different formulations of hormone therapy (HT): oral conjugated equine estrogens (o-CEE; 0.45 mg/d, n = 209), transdermal 17β-estradiol (t-E2; 50 μg/d, n = 201) plus cyclic progesterone (Prometrium, 200 mg) or placebo (PBO, n = 243) affected sleep domains in participants of the Kronos Early Estrogen Prevention Study. Methods: Participants completed the Pittsburgh Sleep Quality Index at baseline and during the intervention at 6, 18, 36, and 48 months. Global sleep quality and individual sleep domain scores were compared between treatments using analysis of covariance, and correlated with vasomotor symptom (VMS) scores using Spearman correlation coefficients. Results: Global Pittsburgh Sleep Quality Index scores (mean 6.3; 24% with score >8) were similar across groups at baseline and were reduced (improved sleep quality) by both HT (average change −1.27 [o-CEE] and −1.32 [t-E2]) when compared with PBO (−0.60; P = 0.001 [o-CEE vs PBO] and P = 0.002 [t-E2 vs PBO]). Domain scores for sleep satisfaction and latency improved with both HT. The domain score for sleep disturbances improved more with t-E2 than o-CEE or PBO. Global sleep scores significantly correlated with VMS severity (r s = 0.170, P < 0.001 for hot flashes; r s = 0.177, P < 0.001 for night sweats). Change in scores for all domains except sleep latency and sleep efficiency correlated with change in severity of VMS. Conclusions: Poor sleep quality is common in recently menopausal women. Sleep quality improved with both HT formulations. The relationship of VMS with domains of sleep suggests that assessing severity of symptoms and domains of sleep may help direct therapy to improve sleep for postmenopausal women.
Longitudinal changes in menopausal symptoms comparing women randomized to low-dose oral conjugated estrogens or transdermal estradiol plus micronized progesterone versus placebo: the Kronos Early Estrogen Prevention Study
Abstract Objective: The objective of the present study was to compare the efficacy of two forms of menopausal hormone therapy in alleviating vasomotor symptoms, insomnia, and irritability in early postmenopausal women during 4 years. Methods: A total of 727 women, aged 42 to 58, within 3 years of their final menstrual period, were randomized to receive oral conjugated estrogens (o-CEE) 0.45 mg (n = 230) or transdermal estradiol (t-E 2 ) 50 μg (n = 225; both with micronized progesterone 200 mg for 12 d each mo), or placebos (PBOs; n = 275). Menopausal symptoms were recorded at screening and at 6, 12, 24, 36, and 48 months postrandomization. Differences in proportions of women with symptoms at baseline and at each follow-up time point were compared by treatment arm using exact χ 2 tests in an intent-to-treat analysis. Differences in treatment effect by race/ethnicity and body mass index were tested using generalized linear mixed effects modeling. Results: Moderate to severe hot flashes (from 44% at baseline to 28.3% for PBO, 7.4% for t-E 2 , and 4.2% for o-CEE) and night sweats (from 35% at baseline to 19% for PBO, 5.3% for t-E 2 , and 4.7% for o-CEE) were reduced significantly by 6 months in women randomized to either active hormone compared with PBO ( P < 0.001 for both symptoms), with no significant differences between the active treatment arms. Insomnia and irritability decreased from baseline to 6 months postrandomization in all groups. There was an intermittent reduction in insomnia in both active treatment arms versus PBO, with o-CEE being more effective than PBO at 36 and 48 months ( P = 0.002 and 0.05) and t-E 2 being more effective than PBO at 48 months ( P = 0.004). Neither hormone treatment significantly affected irritability compared with PBO. Symptom relief for active treatment versus PBO was not significantly modified by body mass index or race/ethnicity. Conclusions: Recently postmenopausal women had similar and substantial reductions in hot flashes and night sweats with lower-than-conventional doses of oral or transdermal estrogen. These reductions were sustained during 4 years. Insomnia was intermittently reduced compared with PBO for both hormone regimens.