The effects of estrogen and selective estrogen receptor modulators on cardiovascular risk factors

Raloxifene, a selective estrogen receptor modulator, favorably alters several markers of cardiovascular risk in healthy postmenopausal women. While many of its effects are similar to those of conventional hormone replacement therapy (HRT), there are also important differences. Raloxifene lowered low-density lipoprotein cholesterol levels similarly to estrogen. However, raloxifene lacked the potentially beneficial effects of HRT on high-density lipoprotein cholesterol levels and plasminogen activation inhibitor-1, as well as the potentially adverse effects of HRT on triglycerides and C-reactive protein. Raloxifene also had a potentially beneficial fibrinogen-lowering effect not seen with conventional HRT. The net effect of these differences is unclear. Proof that raloxifene or HRT reduces the risk of heart disease must await the results of ongoing clinical trials with cardiovascular event end points.

Differential metabolism of human VLDL according to content of ApoE and ApoC-III

We studied the metabolism of very low density lipoprotein (VLDL) and intermediate density lipoprotein (IDL) particles that did or did not have apolipoprotein E (apoE) in 12 normolipidemic women by endogenously labeling plasma apolipoprotein B. The plasma was separated into bound (E+) and unbound (E-) fractions by use of a monoclonal antibody (1D7), and the fractions were ultracentrifuged to yield E+ and E- subfractions of light and dense VLDL and IDL. VLDL E+ and IDL E+ were produced mainly by the liver. VLDL E+ and IDL E+ had lower fractional catabolic rates and much higher apolipoprotein C-III (apoC-III) content than did the corresponding E- particles. Most light VLDL apoE+ underwent lipolysis to dense VLDL E+ with reduced apoC-III content, which was removed from the circulation without conversion to IDL. In contrast, most light VLDL apoE-, poor in apoC-III, was removed from the circulation, and a smaller proportion underwent lipolysis to dense VLDL E-. Most dense VLDL E- underwent lipolysis to IDL E-. The rate constant for lipolysis of dense VLDL to IDL was greater for E- than for E+, and the rate constant for clearance from plasma was greater for dense VLDL E+ than for E-. In conclusion, metabolism of human VLDL particles is influenced by their content of apoE, further modulated by the coexistence of apoC-III.

Effects of raloxifene and hormone replacement therapy on markers of serum atherogenicity in healthy postmenopausal women

OBJECTIVE

To determine the effect of raloxifene (RLX) and hormone replacement therapy (HRT) on non-high density lipoprotein cholesterol (non-HDL-C) levels and the apolipoprotein-B/apolipoprotein-A1 (apo-B/apo-A1) concentration ratio, markers of serum atherogenicity, in postmenopausal women.

METHODS

Three hundred and ninety healthy postmenopausal women aged 45-72 years were enrolled in a double-blind, randomized, placebo-controlled, parallel trial at eight outpatient sites in the United States. Women were randomly assigned to receive continuous combined HRT (0.625 mg/day conjugated equine estrogen and 2.5 mg/day medroxyprogesterone acetate), 60 or 120 mg/day raloxifene, or placebo for 6 months. Serum concentrations of non-HDL cholesterol and the apo-B/apo-A1 concentration ratio were measured in serum samples obtained at baseline and at 6 months of treatment.

RESULTS

At 6 months, non-HDL-C and apo-B/apo-A1 were significantly reduced by 60 mg/day RLX (10 and 11%, respectively), 120 mg/day RLX (9 and 12%, respectively) and HRT (10 and 12%, respectively), compared with placebo. The effect of all treatments to lower non-HDL-C and apo-B/apo-A1 was greatest in women with hypercholesterolemia (total-C>240 mg/dl) at baseline. Among women with undesirable (>160 mg/dl) non-HDL cholesterol at baseline, RLX and HRT lowered the percentage of these women remaining above this threshold after 6 months (placebo, 89%; 60 mg/day RLX, 61%; 120 mg/day RLX, 74%; HRT, 58%). Similar results were observed for women with high (>190 mg/dl) non-HDL cholesterol at baseline.

CONCLUSION

In healthy postmenopausal women, RLX and HRT lower serum non-HDL-C and apo-B/apo-A1, indicators of serum atherogenicity, to a similar extent.

Comparison of alendronate and intranasal calcitonin for treatment of osteoporosis in postmenopausal women

This study compared the effects of oral alendronate and intranasal calcitonin for treatment of osteoporosis in postmenopausal women. Women at least 5 yr postmenopause (n = 299) were randomized to either 10 mg alendronate, matching alendronate placebo, or open-label intranasal calcitonin 200 IU daily for 12 months. Hip and spine bone mineral density (BMD) and markers of bone turnover were measured, and safety and tolerability were assessed. Alendronate produced greater increases in BMD than calcitonin at 12 months at the lumbar spine (5.16% vs. 1.18%; P < 0.001), trochanter (4.73% vs. 0.47%; P < 0.001), and femoral neck (2.78% vs. 0.58%; P < 0.001). Changes in BMD with calcitonin were greater than with placebo at the femoral neck, but were not different from placebo at either the trochanter or lumbar spine. Greater decreases in bone turnover were seen with alendronate than with calcitonin (serum bone-specific alkaline phosphatase, 43% vs. 9%, P < 0.001; urinary N-telopeptide, 62% vs. 11%, P < 0.001). Similar percentages of patients in each group reported an adverse experience during the study. We conclude that, in postmenopausal women with osteoporosis, 12 months of therapy with alendronate produced significantly greater increases in BMD of the hip and spine and greater decreases in bone turnover than intranasal calcitonin.

The effects of hormone replacement therapy and raloxifene on C-reactive protein and homocysteine in healthy postmenopausal women: a randomized, controlled trial

C-Reactive protein and homocysteine are independent risk factors for the development of cardiovascular disease. This study compared the effects of hormone replacement therapy (HRT) and raloxifene on serum C-reactive protein and homocysteine levels as markers of cardiovascular risk in healthy postmenopausal women. Healthy postmenopausal women (n = 390) were enrolled in a double blind, randomized, placebo-controlled, 6-month trial at eight out-patient sites in the United States. Women were randomly assigned to receive continuous combined HRT (0.625 mg/day conjugated equine estrogen and 2.5 mg/day medroxyprogesterone acetate), raloxifene (60 or 120 mg/day), or placebo for 6 months. C-Reactive protein and homocysteine were measured in baseline and 6-month serum samples. HRT increased C-reactive protein levels by 84% (P<0.001), whereas raloxifene (60 and 120 mg/day) had no significant effect (-6% and -4%;, respectively; P>0.2). Raloxifene (60 and 120 mg/day) significantly lowered serum levels ofhomocysteine by 8% (P = 0.014) and 6% (P = 0.024), respectively, similar to the 7% (P = 0.014) reduction obtained with HRT. We conclude that HRT and raloxifene lower serum homocysteine levels to a comparable extent in postmenopausal women. Whereas cardiovascular risk predicted by C-reactive protein in healthy postmenopausal women is not influenced by raloxifene, the relationship between elevated C-reactive protein levels with HRT and cardiovascular disease events requires further study.

A 12-month comparative study of raloxifene, estrogen, and placebo on the postmenopausal endometrium

OBJECTIVE

To determine the effects of a selective estrogen receptor modulator, raloxifene, on postmenopausal endometrium.

METHODS

Healthy postmenopausal women (n = 415) were randomly assigned to one of the following four groups: 60 or 150 mg/day raloxifene hydrochloride, 0.625 mg/day conjugated equine estrogens, or placebo, and treated for 1 year. Endometrial biopsies were obtained in a blinded fashion at baseline and every 6 months after the ultrasound studies. Transvaginal ultrasound, with uterine size measurements, was done at baseline and at 3-month intervals. Saline-infusion sonohysterography was done at baseline and every 6 months.

RESULTS

There were no statistically significant differences in baseline characteristics. Mean endometrial thickness, measured by transvaginal ultrasound, was unchanged from baseline to end point in the placebo and raloxifene groups, whereas in the estrogen group it was significantly thicker by 5.5 mm (P < .001). Mean uterine volume, calculated from transvaginal ultrasound measurements, was higher in the estrogen group only (22 cm3, P < .001). Of the 358 women with paired biopsies, endometrial hyperplasia was present in 2.1%, 0%, and 26.1% of the end-point biopsies in the placebo, raloxifene, and estrogen groups, respectively (P < .001). Proliferative endometrium was present in 2.1% of the end-point biopsies in the placebo group, 1.7% in the combined raloxifene groups, and 39.8% in the estrogen group (P < .001).

CONCLUSION

Raloxifene, at 60 or 150 mg/day for 1 year, did not stimulate the postmenopausal endometrium. End-point endometrial thickness, morphology, and uterine volume in the raloxifene groups were similar to those observed at baseline and in the placebo group.

Addition of alendronate to ongoing hormone replacement therapy in the treatment of osteoporosis: a randomized, controlled clinical trial

Alendronate and estrogen are effective therapies for postmenopausal osteoporosis, but their efficacy and safety as combined therapy are unknown. The objective of this study was to evaluate the addition of alendronate to ongoing hormone replacement therapy (HRT) in the treatment of postmenopausal women with osteoporosis. A total of 428 postmenopausal women with osteoporosis, who had been receiving HRT for at least 1 yr, were randomized to receive either alendronate (10 mg/day) or placebo. HRT was continued in both groups. Changes in bone mineral density (BMD) and biochemical markers of bone turnover were assessed. Compared with HRT alone, at 12 months, alendronate plus HRT produced significantly greater increases in BMD of the lumbar spine (3.6% vs. 1.0%, P < 0.001) and hip trochanter (2.7% vs. 0.5%, P < 0.001); however, the between-group difference in BMD at the femoral neck was not significant (1.7% vs. 0.8%, P = 0.072). Biochemical markers of bone turnover (serum bone-specific alkaline phosphatase and urine N-telopeptide) decreased significantly at 6 and 12 months with alendronate plus HRT, and they remained within premenopausal levels. Addition of alendronate to ongoing HRT was generally well tolerated, with no significant between-group differences in upper gastrointestinal adverse events or fractures. This study demonstrated that, in postmenopausal women with low bone density despite ongoing treatment with estrogen, alendronate added to HRT significantly increased bone mass at both spine and hip trochanter and was generally well tolerated.

Estradiol with or without progesterone and ambulatory blood pressure in postmenopausal women

The purpose of this study was to determine whether transdermal estradiol and intravaginal progesterone given in doses to mimic the premenopausal state would lower blood pressure (BP) in postmenopausal women. Fifteen healthy postmenopausal women were studied in each of 3 conditions: on placebo, after 8 weeks of transdermal estradiol 0.2 mg twice per week, and again 2 weeks after addition of intravaginal progesterone 300 mg/d. Women were studied at each point after 2 days of 100 mmol/d sodium intake. Twenty-four-hour ambulatory BP monitoring was performed, and blood was assayed for estradiol, progesterone, and hormones of the renin-angiotensin-aldosterone system (RAAS). ANOVA with pairwise comparisons was used for analysis. Urinary sodium excretion was similar at each time point. Levels of estrogen and progesterone similar to those in premenopausal women were achieved. On estradiol, nocturnal systolic BP (110+/-3 mm Hg), diastolic BP (63+/-2 mm Hg), and mean BP (77+/-2 mm Hg) fell significantly (P<0.02) compared with placebo systolic BP (116+/-2 mm Hg), diastolic BP (68+/-2 mm Hg), and mean BP (82+/-2 mm Hg). Daytime BP followed the same trend but was significantly lower only for mean BP. There was no activation of the RAAS. The addition of progesterone resulted in no further fall in BP but a significant activation of the RAAS. Thus, contrary to what is often assumed, administration of estradiol with or without progesterone not only did not raise BP but rather substantially lowered BP. This BP-lowering effect may be responsible for the lower incidence of hypertension in premenopausal than in postmenopausal women.

Relationship between serum estradiol levels and the increases in high-density lipoprotein levels in postmenopausal women treated with oral estradiol

Postmenopausal women are prescribed a standard dose of estrogen, which is optimal for a population but not for all individuals. We wished to identify if an individual's estradiol level can indicate the minimum effective dose of estrogen which maximally increases high-density lipoprotein (HDL) levels, which could be cardioprotective. We performed a prospective, double-blind crossover study in 19 healthy postmenopausal women, receiving three treatments in random order for 9 weeks each: a) placebo, b) 1 mg oral estradiol daily, and c) 2 mg oral estradiol daily. Lipoprotein and estradiol (E2) levels were measured 10-12 h after pills were taken. E2 levels with 1 mg estradiol were positively correlated with the increases in HDL levels (r = 0.70, P < 0.01). Only the eight subjects who had E2 levels < 50 pg/mL after 1 mg estradiol treatment demonstrated further increases in HDL levels by increasing the daily dose to 2 mg (by 3 +/- 5% with 1 mg estradiol and by 13 +/- 7% with 2 mg). The other 11 subjects who had E2 levels > 50 pg/mL with 1 mg estradiol had no additional benefit from increasing the estradiol dose (HDL increased by 13 +/- 9% with 1 mg, and by 17 +/- 10% with 2 mg). Thus, measurement of an E2 level the morning after taking 1 mg estradiol at bedtime identifies who may benefit from improvement in HDL levels by increasing to a 2-mg dose.

Estradiol therapy combined with progesterone and endothelium-dependent vasodilation in postmenopausal women

BACKGROUND

Epidemiological studies indicate that estrogen replacement therapy decreases the risk of cardiovascular events in postmenopausal women. Estrogen may confer cardiovascular protection by improving endothelial function because it increases endothelium-dependent vasodilation. It is not known whether progesterone attenuates the beneficial effects of estrogen on endothelial function.

METHODS AND RESULTS

Seventeen postmenopausal women with mild hypercholesterolemia were enrolled in a placebo-controlled, crossover trial to evaluate the effect of transdermal estradiol, with and without vaginal micronized progesterone, on endothelium-dependent vasodilation in a peripheral conduit artery. Brachial artery diameter was measured with high-resolution B-mode ultrasonography. To assess endothelium-dependent vasodilation, brachial artery diameter was determined at baseline and after a flow stimulus induced by reactive hyperemia. To assess endothelium-independent vasodilation, brachial artery diameter was measured after administration of sublingual nitroglycerin. During estradiol therapy, reactive hyperemia caused an 11.1+/-1.0% change in brachial artery diameter compared with 4. 7+/-0.6% during placebo therapy (P<0.001). Progesterone did not significantly attenuate this improvement. During combined estrogen and progesterone therapy, flow-mediated vasodilation of the brachial artery was 9.6+/-0.8% (P=NS versus estradiol alone). Endothelium-independent vasodilation was not altered by estradiol therapy, either with or without progesterone, compared with placebo. There was a modest decrease in total and LDL cholesterol during treatment both with estradiol alone and when estradiol was combined with progesterone (all P<0.001 versus placebo). In a multivariate analysis that included serum estradiol, progesterone, total and LDL cholesterol concentrations, blood pressure, and heart rate, only the estradiol level was a significant predictor of endothelium-dependent vasodilation.

CONCLUSIONS

The addition of micronized progesterone does not attenuate the favorable effect of estradiol on endothelium-dependent vasodilation. The vasoprotective effect of hormone replacement therapy may extend beyond its beneficial actions on lipids.

Fibrinolytic potential is significantly increased by oestrogen treatment in postmenopausal women with mild dyslipidaemia

OBJECTIVE

To study the effects of oestrogen replacement treatment on fibrinolytic potential in postmenopausal women.

DESIGN

Randomised, double blind, placebo controlled trial of oral 17 beta-oestradiol.

SETTING

Subjects were evaluated in the outpatient setting.

PATIENTS

Nineteen postmenopausal women with mild dyslipidaemia, aged 44 to 69 years (mean (SD) 55.7 (6.7)).

MAIN OUTCOME MEASURES

Fibrinolytic activity (fibrin plate assay) and tissue plasminogen activator (t-PA) antigen were measured at baseline and after three, six, and nine weeks of each treatment.

RESULTS

After nine weeks of 2 mg oestradiol treatment, there was a significant increase in fibrinolytic potential compared with placebo, as indicated by an increase in fibrinolytic activity (mean (SEM), 80 (9) v 54 (5) mm2 of lysis in the fibrin plate, 2 mg v placebo, p = 0.002) and a decrease in t-PA antigen (5.8 (0.9) v 8.4 (1.2) ng/ml, 2 mg v placebo, p < 0.001). There was a similar trend with the 1 mg dose but the changes were less noticeable.

CONCLUSIONS

Hormone replacement treatment with 17 beta-oestradiol for nine weeks significantly increased fibrinolytic potential in postmenopausal women with mild dyslipidaemia. This suggests that the cardioprotective effect of oestrogen may be mediated, in part, by an increase in fibrinolytic potential.

Metabolism of Apo(a) and ApoB100 of lipoprotein(a) in women: effect of postmenopausal estrogen replacement

The metabolism in plasma of apo(a) and apoB100, the major protein components of lipoprotein(a) [Lp(a)], and the mechanism by which estrogen lowers Lp(a) concentration are both not well understood. Estrogen or placebo were administered to 12 postmenopausal women in a double-blind cross-over design; and after each treatment, apo(a) and apoB100 in Lp(a) were endogenously labeled by i.v. trideuterated leucine. After estrogen treatment, mean Lp(a) concentration decreased during estrogen, from 25 mg/dL, by 20% (P < 0.01); and the mean production rate of apo(a) decreased, from 0.31 nmol/kg.day, by 34% (P = 0.046). In contrast, the mean fractional catabolic rates of apo(a) were similar, 0.36 vs. 0.31/day (P = 0.23). In 6 women, the kinetics of apo(a) and apoB100, the two major proteins of Lp(a), were studied during estrogen and placebo periods. During both periods, the rate of appearance of tracer was similar in Lp(a)-apo(a) and Lp(a)-apoB100, as were the resulting metabolic rates and the changes during estrogen treatment. In conclusion, the findings are more compatible with intracellular synthesis of Lp(a) from nascent apo(a) and apoB100 than extracellular assembly from plasma low-density lipoproteins. Reduced flux into plasma of Lp(a), an atherogenic lipoprotein, could contribute to the lower cardiovascular disease rates in women receiving estrogen replacement therapy.

Thermal balloon and rollerball ablation to treat menorrhagia: a multicenter comparison

OBJECTIVE

To compare the clinical efficacy and safety of a thermal uterine balloon system with hysteroscopic rollerball ablation in the treatment of dysfunctional uterine bleeding.

METHODS

Two hundred fifty-five premenopausal women were treated in a randomized multicenter study comparing thermal uterine balloon therapy with hysteroscopic rollerball ablation for the treatment of menorrhagia. Preprocedural and postprocedural menstrual diary scores and quality-of-life questionnaires were obtained. Twelve-month follow-up data are presented on 239 women.

RESULTS

Twelve-month results indicated that both techniques significantly reduced menstrual blood flow with no clinically significant difference between the two groups as reflected by return to normal bleeding or less (balloon 80.2% and rollerball ablation 84.3%). Multiple quality-of-life questionnaire results were also similar, including percent of patients highly satisfied with their results (balloon 85.6% compared with rollerball 86.7%). A 90% decrease in diary scores was seen in more than 60% of patients in both groups. Procedural time was reduced significantly in the uterine balloon therapy group. Intraoperative complications occurred in 3.2% of the hysteroscopic rollerball patients, whereas no intraoperative complications occurred in the thermal balloon group.

CONCLUSION

In the treatment of dysfunctional uterine bleeding, uterine balloon therapy is as efficacious as hysteroscopic rollerball ablation and may be safer.

Effects of raloxifene on serum lipids and coagulation factors in healthy postmenopausal women

CONTEXT

Raloxifene is a selective estrogen receptor modulator that has estrogen-agonistic effects on bone and estrogen-antagonistic effects on breast and uterus.

OBJECTIVE

To identify the effects of raloxifene on markers of cardiovascular risk in postmenopausal women, and to compare them with those induced by hormone replacement therapy (HRT).

DESIGN

Double-blind, randomized, parallel trial.

SETTING

Eight sites in the United States.

PARTICIPANTS

390 healthy postmenopausal women recruited by advertisement.

INTERVENTION

Participants were randomized to receive 1 of 4 treatments: raloxifene, 60 mg/d; raloxifene, 120 mg/d; HRT (conjugated equine estrogen, 0.625 mg/d, and medroxyprogesterone acetate, 2.5 mg/d); or placebo.

MAIN OUTCOME MEASURES

Change and percent change from baseline of lipid levels and coagulation parameters after 3 months and 6 months of treatment.

RESULTS

At the last visit completed, compared with placebo, both dosages of raloxifene significantly lowered low-density lipoprotein cholesterol (LDL-C) by 12% (P < .001), similar to the 14% reduction with HRT (P < .001). Both dosages of raloxifene significantly lowered lipoprotein(a) by 7% to 8% (P < .001), less than the 19% decrease with HRT (P<.001). Raloxifene increased high-density lipoprotein-2 cholesterol (HDL2-C) by 15% to 17% (P < .05), less than the 33% increase with HRT (P < .001). Raloxifene did not significantly change high-density lipoprotein cholesterol (HDL-C), triglycerides, or plasminogen activator inhibitor-1 (PAI-1); whereas HRT increased HDL-C by 11% and triglycerides by 20%, and decreased PAI-1 by 29% (for all, P < .001). Raloxifene significantly lowered fibrinogen by 12% to 14% (P < .001), unlike HRT, which had no effect. Neither treatment changed fibrinopeptide A or prothrombin fragment 1 and 2.

CONCLUSIONS

Raloxifene favorably alters biochemical markers of cardiovascular risk by decreasing LDL-C, fibrinogen, and lipoprotein(a), and by increasing HDL2-C without raising triglycerides. In contrast to HRT, raloxifene had no effect on HDL-C and PAI-1, and a lesser effect on HDL2-C and lipoprotein(a). Further clinical trials are necessary to determine whether these favorable biochemical effects are associated with protection against cardiovascular disease.

Effect of estrogen on very low density lipoprotein and low density lipoprotein subclass metabolism in postmenopausal women

Estrogen decreases low density lipoprotein (LDL) particle size, and smaller LDL particles are associated with coronary atherosclerosis. To understand the metabolic basis for this change, we studied the effect of oral 17 beta-estradiol (2 mg/day) on apolipoprotein B-100 (apoB) metabolism, in eight healthy postmenopausal women. The study was a randomized, double blinded, placebo-controlled, cross-over trial with intervention sequences of 6 weeks each. ApoB in very low density lipoprotein, intermediate density lipoprotein, and LDL subclasses was endogenously labeled with [D3]L-leucine, and metabolic rates were calculated by computer modeling. The overall effect of oral estrogen therapy on apoB metabolism was to accelerate the fractional catabolic rates of all particles studied and production rates of all except IDL. For light LDL (density = 1.019-1.036 g/mL), estrogen increased the mean fractional catabolic rate by 63% from 0.59 to 0.96 pools/day (P = 0.02), whereas the production rate increased by a lesser amount (42%) from 575 to 817 mg/day (P = 0.10). These metabolic changes reduced light LDL cholesterol and apoB concentrations by 26% (P = 0.005) and 19% (P = 0.03), respectively. In contrast, dense LDL (density = 1.036-1.063 g/mL) cholesterol and apoB concentrations were unchanged by the intervention, as both the apoB fractional catabolic rate and production rate were significantly increased by similar amounts, 39% (from 0.41 to 0.57 pools/day, P = 0.01) and 38% (from 434 to 601 mg/day; P = 0.003), respectively. Estrogen decreased the predominant LDL peak particle size from 273 to 268 A (P = 0.04). Thus, estrogen therapy increases the clearance of both light and dense LDL, counteracting increases in production rates. The reduced plasma residence times of light and dense LDL both may be antiatherogenic, even though, for dense LDL, the concentration did not change.

Estrogen absorption and metabolism in postmenopausal women with end-stage renal disease

Women with end-stage renal disease (ESRD) have a higher rate of death from heart disease than women with normal renal function. Because estrogen replacement therapy may significantly decrease the incidence of death due to cardiovascular disease in postmenopausal women with normal renal function, their use has been considered for women with ESRD. However, the pharmacokinetics of estrogen have not been studied in postmenopausal women with ESRD to determine the optimal estrogen dose. Six postmenopausal women with ESRD receiving maintenance hemodialysis and six controls matched for body mass index were admitted to the in-patient Clinical Research Center. A 1- or 2-mg oral estradiol (E2) pill was given while subjects fasted. Blood sampling was performed over the next 24 h for measurement of E2, estrone (E1), albumin, and sex hormone-binding globulin (SHBG). Three weeks later, the subjects were given the other E2 dose under identical conditions. At baseline, total and free E2 levels were higher in the subjects with ESRD than in controls (P = 0.0005 and 0.0035, respectively). After ingestion of 1 and 2 mg E2, total and free E2 levels remained significantly higher in the ESRD subjects from 2-8 h after treatment (P < or = 0.05). After 1 mg oral E2, total serum E2 peaked at 65 pg/mL at 4 h in ESRD subjects and at 27 pg/mL in control subjects at 8 h. After 2 mg oral E2 treatment, total serum E2 peaked at 8 h in both ESRD and control subjects, with levels of 99 and 37 pg/mL, respectively. E1 was higher in the subjects with ESRD than in the control subjects at baseline (P < 0.05). After ingestion of 1 mg E2, E1 concentrations were not significantly higher in ESRD than in control subjects, peaking at 180 and 121 pg/mL, respectively (P = 0.3). E1 concentrations were higher in ESRD than in control subjects after the ingestion of 2 mg E2, with peak levels of 376 and 201 pg/mL, respectively (P = 0.03). Total and free E2 levels are higher in patients with ESRD than in control subjects at baseline and after E2 ingestion, indicating that renal failure alters the pharmacokinetics of both endogenous and exogenous E2. Therefore, conventional E2 doses used in individuals with normal renal function may be excessive for patients with ESRD.

Sex hormones, lipoproteins, and vascular reactivity

The HDL-raising effect of estrogen replacement is mediated by an increase in HDL-apolipoprotein A-I production and not by a decrease in the clearance rate. Large-scale clinical trials have shown that medroxyprogesterone acetate removes most of the HDL-raising effects of concomitant estrogen treatment. Testosterone decreases HDL levels in both men and women. Lipoprotein (a) levels are reduced by estrogen replacement, but are not affected by medroxyprogesterone. The acute systemic administration of estrogen to postmenopausal women improves the endothelium-dependent vasodilation of coronary arteries and forearm resistance vessels. Usual doses of oral estrogen replacement therapy improve the endothelium-dependent and endothelium-independent vasodilator responses in the forearm in women who have risk factors for atherosclerosis. These effects may be mediated by an antioxidant action of estrogen.

The effects of ethanol on the clearance of estradiol in postmenopausal women

OBJECTIVE

To determine whether acute alcohol ingestion affects the pattern of decline of circulating E2 levels after removal of transdermal E2 patches.

DESIGN

A randomized, placebo-controlled, crossover study.

SETTING

The study was performed in the Clinical Research Center of the Brigham and Women's Hospital.

PARTICIPANTS

Twelve healthy postmenopausal women were enrolled.

INTERVENTIONS

Transdermal E2 patches, 0.15 mg, were applied 13 hours before subjects ingested alcohol (1 mL/kg 95% ethanol) or carbohydrate placebo punch. The patches were removed immediately after drink ingestion.

MAIN OUTCOME MEASURES

Estradiol, estrone (E1), and ethanol levels were measured.

RESULTS

Serum samples were obtained for 40 minutes before drink ingestion and 5 hours after drink ingestion and E2 patch removal. At the time of patch removal, E2 levels rose acutely over 10 minutes and then decreased rapidly, suggesting a bolus effect that was more marked after ethanol ingestion. After ethanol ingestion and patch removal the half-life of E2 was calculated to be 378 minutes, and after carbohydrate punch and patch removal 245 minutes. There were no significant changes in E1 concentrations over the time course of the study between groups.

CONCLUSIONS

Ethanol ingestion may decrease E2 clearance after removal of transdermal E2 patches.

The effect of acute ethanol ingestion on estrogen levels in postmenopausal women using transdermal estradiol

OBJECTIVE

To determine whether acute alcohol ingestion raises estradiol (E2) and estrone (E1) levels in a randomized, controlled, crossover study on postmenopausal women using transdermal E2.

METHODS

Healthy, non-smoking postmenopausal women (n = 7) using no medications were enrolled. Transdermal E2, 0.15 mg, was applied 13 hours before the subjects ingested alcohol (1 mL/kg 95% ethanol) or isocaloric carbohydrate punch. Serum samples were obtained for 40 minutes before drink ingestion and 6 hours after drink ingestion and were assayed for E2 and E1.

RESULTS

Ethanol levels peaked 60 minutes after the start of ethanol-drink ingestion, at 25.4 mmol/L (117 mg/dL). Estradiol levels rose significantly above the mean baseline of 657 pmol/L (179 pg/mL) after ethanol-drink ingestion (P < or = .01), with a mean peak of 804 pmol/L (219 pg/mL) 35 minutes after the start of drink ingestion, and were significantly greater than the E2 levels that followed the carbohydrate drink (P < or = .0001). There were no significant changes in E2 or E1 levels after carbohydrate-drink ingestion.

CONCLUSIONS

We conclude that ethanol ingestion may acutely raise circulating E2 concentrations in women using transdermal E2.

Effect of acute ethanol ingestion on prolactin in menopausal women using estradiol replacement

Epidemiologic studies suggest that women who consume ethanol are at an increased risk for developing breast cancer. Two randomized, crossover studies were performed to examine the effects of ethanol on prolactin in menopausal women using transdermal estradiol. In study 1, transdermal estradiol patches (0.15 mg) were administered to menopausal women (n = 7) the day before ethanol administration. At 8.00 h, the women ingested ethanol (1 ml/kg, 95% ethanol) or an isocaloric carbohydrate drink. Prolactin levels were measured frequently for 6.3 h. Serum ethanol levels reached a broad peak from 40 to 100 min after initiation of ethanol ingestion. Serum prolactin levels were significantly higher after ethanol ingestion than after the isocaloric carbohydrate drink ingestion (p < 0.03). Study 2 was identical to study 1 except that the transdermal estradiol patches were removed after completion of ethanol or carbohydrate ingestion. In study 2, serum prolactin was greater after ethanol ingestion than after carbohydrate ingestion (p < 0.001). In menopausal women using transdermal estradiol, acute ethanol ingestion is associated with an increase in serum prolactin.

Estrogen improves endothelium-dependent, flow-mediated vasodilation in postmenopausal women

OBJECTIVE

To assess the effect of estrogen replacement therapy on endothelium-dependent vasodilation in postmenopausal women.

DESIGN

Double-blind, placebo-controlled, crossover trial.

SETTING

University medical center.

PATIENTS

13 postmenopausal women aged 44 to 69 years (average age, 55 +/- 7 years).

INTERVENTION

Patients were randomly assigned to receive placebo, oral estradiol at a dose of 1 mg/d, and oral estradiol at a dose of 2 mg/d. Each treatment phase lasted 9 weeks.

MEASUREMENTS

High-resolution ultrasonography was used to measure vascular reactivity in a peripheral conduit vessel, the brachial artery. Endothelium-dependent vasodilation was determined by measuring the change in brachial artery diameter during increases in flow induced by reactive hyperemia. Endothelium-independent vasodilation was measured after sublingual nitroglycerin was administered.

RESULTS

Flow-mediated, endothelium-dependent vasodilation of the brachial artery was greater when patients received estradiol (13.5% and 11.6% for 1-mg and 2-mg doses, respectively) than when patients received placebo (6.8%; P < 0.05 for each dose compared with placebo). In contrast, estrogen administration had no effect on endothelium-independent vasodilation as assessed by sublingual nitroglycerin.

CONCLUSION

Short-term estrogen replacement therapy improves flow-mediated endothelium-dependent vasodilation in postmenopausal women. This improvement may be mediated by a direct effect of estrogen on vascular function or may be induced through modification of lipoprotein metabolism.

Effects of postmenopausal hormone replacement with oral and transdermal estrogen on high density lipoprotein metabolism

Estrogen treatment raises plasma high density lipoprotein (HDL) levels, which may reduce cardiovascular risk. To identify the responsible mechanisms as well as the importance of the route of administration, we treated eight healthy postmenopausal women in a double-blind crossover study with three treatments for 6 weeks each: oral estradiol, 2 mg daily; transdermal estradiol, 0.1 mg twice weekly; and placebo. At the end of each treatment, apoA-I of HDL2 (d 1.063-1.125 g/ml) and HDL3 (d 1.125-1.210 g/ml) was endogenously labeled by a constant intravenous infusion of trideuterated leucine. HDL2 and HDL3 were separated by preparative ultracentrifugation. The pool sizes and enrichment curves of HDL apoA-I were used to calculate production rates and fractional catabolic rates (FCR). Oral estradiol increased the levels of HDL2 apoA-I by 37% (P < 0.005) and of HDL3 apoA-I by 11% (P < 0.05). These increased apoA-I levels resulted entirely from increased production, by 36% for HDL2 (P < 0.01), and by 19% for HDL3, (P < 0.05) as their FCRs were unchanged (0.20 pool/d with placebo and 0.21 with estradiol for HDL2, and 0.19 with placebo and 0.21 with estradiol for HDL3). The isotopic enrichment curves of HDL2 apoA-I and HDL3 apoA-I were identical, implying that apoA-I rapidly cycles between HDL particles, or that rapid interconversion of these subfractions occurs. The changes in HDL apoA-I metabolic rates were positively correlated with changes in VLDL-apoB metabolic rates measured previously. Transdermal estradiol, with systemic potency similar to that of oral estradiol, had no significant effect on HDL levels or metabolic rates. Thus, the "first pass" effect of oral estradiol on the liver and/or intestine appears to increase HDL apoA-I levels (particularly in HDL2) by increasing HDL apoA-I production, and not by reducing HDL apoA-I catabolism.

Sex hormones and lipoprotein metabolism

Previous findings of increased production of large VLDL particles by estrogen have been confirmed in a trial using estrogen-dominant oral contraceptives. Estrogen has been found to have LDL subclass-specific effects and to shift the distribution of apolipoprotein (apo)E from HDL to VLDL. Several recent studies document decreases in lipoprotein (a) [Lp(a)] levels, but the metabolic mechanism is yet unknown. The effects of progestational agents on lipoprotein metabolism remain unclear in view of conflicting reports.

Effect of postmenopausal estrogen replacement on plasma Lp(a) lipoprotein concentrations

BACKGROUND

Women who receive postmenopausal estrogen replacement experience a lower rate of coronary heart disease than women who do not receive these hormones. Evidence suggests that mechanisms in addition to decreases in plasma low-density lipoprotein levels and increases in high-density lipoprotein concentrations are responsible for the apparent beneficial effect of estrogens. Therefore, we studied the effect of estrogen on plasma Lp(a) lipoprotein, newly suggested to be a risk factor for coronary heart disease in postmenopausal women.

METHODS

The 31 healthy, normolipidemic subjects received placebo and conjugated equine estrogens (0.625 and 1.25 mg/d) for 3-month periods in a randomized, double-blind, crossover trial.

RESULTS

The mean Lp(a) lipoprotein concentration was 20.4 +/- 14.6 mg/dL during placebo treatment; it decreased by 14% (P < .01) with 0.625 mg of conjugated estrogens and by 16% (P < .005) with 1.25 mg. The Lp(a) lipoprotein concentration during placebo treatment was not significantly correlated with the responses to either dose of estrogen. There was no effect of estrogen on the plasma concentration of cholesterol ester transfer protein, suggesting that this protein is not involved in estrogen-induced changes in very-low-density lipoprotein or high-density lipoprotein concentrations and composition.

CONCLUSIONS

Estrogen decreases the plasma Lp(a) lipoprotein concentration, which could explain some of the protective effect of estrogen replacement therapy on coronary heart disease.

Differential effects of estrogen on low-density lipoprotein subclasses in healthy postmenopausal women

The use of estrogen by postmenopausal women decreases plasma low-density lipoprotein (LDL) cholesterol levels. To determine whether LDL subclass profiles influence this response, we studied 31 healthy postmenopausal women who were administered two doses (0.625 and 1.25 mg/d) of conjugated equine estrogen in a placebo-controlled double-blind crossover study. Lipid-stained gradient gels were used to categorize LDL subclass patterns. All women were classified as LDL subclass pattern A (predominant LDL peak > or = 260 A). Within the pattern A classification, there were 12 women during placebo treatment with LDL subclass I pattern (predominant LDL peak > 271 A) and 19 women with LDL subclass II pattern (predominant LDL peak < or = 271 and > or = 260 A). Postmenopausal women with LDL subclass I on placebo treatment had significantly lower LDL cholesterol levels compared with women having LDL subclass II (126 +/- 28 v 147 +/- 23 mg/dL, P < .03). Postmenopausal women with LDL subclass I also had significantly (P < .05) lower very-low-density lipoprotein (VLDL) cholesterol, VLDL triglyceride, and VLDL apo B levels and significantly higher (P < .05) high-density lipoprotein 2 (HDL2) cholesterol, HDL3 cholesterol, and HDL2 apo A-I levels. Estrogen replacement significantly (P < .05) decreased LDL cholesterol levels and increased VLDL and LDL triglyceride, HDL2 and HDL3 cholesterol and apo A-I, and HDL2 apo A-II levels to a similar extent in postmenopausal women with LDL I or II subclass patterns.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of low dose oral contraceptives on very low density and low density lipoprotein metabolism

Oral contraceptives (OC) raise plasma triglyceride and VLDL levels, which may be of concern, since some conditions characterized by elevated triglycerides are associated with atherosclerosis. To identify the responsible mechanism, we studied 11 healthy premenopausal women, 5 of whom were taking OC containing 0.035 mg ethinyl estradiol, and 6 of whom were not. Their rates of VLDL and LDL metabolism were measured by endogenously labeling apoB, the protein component of VLDL and LDL, by an intravenous infusion of deuterated leucine. OC use had the greatest effect on the large, triglyceride-rich VLDL subfraction (Sf 60-400), increasing plasma levels threefold and production rates fivefold (P < 0.05). Among OC users, small VLDL (Sf 20-60) levels were 2.2 times higher, and production rates were 3.4-fold higher (P < 0.05). The fractional catabolic rates of large and small VLDL were similar among OC users and nonusers. LDL levels and metabolic rates were not significantly different between the two groups. Thus, contemporary low dose OC substantially raise VLDL levels by increasing the production rate of large, triglyceride-rich VLDL, and not by slowing VLDL catabolism. Since VLDL catabolism is not impaired, we speculate that the hypertriglyceridemia induced by OC may be less atherogenic than that of hypertriglyceridemia resulting from impaired lipolysis. This may explain why long-term OC use does not appear to promote atherosclerosis.

Acute adrenocorticotropin stimulation of postmenopausal cigarette smokers and nonsmokers: effects on steroidogenesis

Cigarette smoking has been associated with elevated levels of A and DHEAS in postmenopausal women. One possible mechanism postulated for this effect is enzymatic blockage by components of cigarette smoke. In this study, acute ACTH stimulation of postmenopausal cigarette smokers did not result in abnormal elevations of precursor steroids. Other possible mechanisms may be operative in vivo to account for the previously reported findings.

Coagulation activation following estrogen administration to postmenopausal women

We investigated coagulation system activation following estrogen treatment in 29 healthy postmenopausal women. Study participants received conjugated estrogens at 0.625 and 1.25 mg per day, and placebo for 3-month periods in a randomized crossover protocol. Blood samples were obtained on two consecutive days at the end of each treatment period for immunoassays of F1+2 and fibrinopeptide A (FPA), markers of factor Xa action on prothrombin and thrombin action on fibrinogen in vivo, respectively. Treatment with estrogens at a dose of 0.625 or 1.25 mg resulted in significant increases in mean F1+2 levels of 40 and 98%, respectively, and in mean FPA levels of 37 and 71%, respectively. The measurements of F1+2 were significantly higher in women receiving 1.25 mg of estrogen than 0.625 mg. We also observed significant declines in the levels of antithrombin III and total protein S antigen. Immunologic levels of protein C increased modestly at only the 1.25 mg estrogen dose level. These data indicate that low doses of oral estrogens (< or = 1.25 mg per day) frequently increase the amount of thrombin generated in vivo. Our observations may help to explain the increased thrombotic risk that has been observed with higher doses of this medication (> or = 2.5 mg).

Effects of postmenopausal estrogen replacement on the concentrations and metabolism of plasma lipoproteins

BACKGROUND

Postmenopausal estrogen-replacement therapy may reduce the risk of cardiovascular disease, and this beneficial effect may be mediated in part by favorable changes in plasma lipid levels. However, the effects on plasma lipoprotein levels of postmenopausal estrogens in the low doses currently used have not been precisely quantified, and the mechanism of these effects is unknown.

METHODS

We conducted two randomized, double-blind crossover studies in healthy postmenopausal women who had normal lipid values at base line. In study 1, 31 women received placebo and conjugated estrogens at two doses (0.625 mg and 1.25 mg per day), each treatment for three months. In study 2, nine women received placebo, oral micronized estradiol (2 mg per day), and transdermal estradiol (0.1 mg twice a week), each treatment for six weeks. The metabolism of very-low-density lipoprotein (VLDL) and low-density lipoprotein (LDL) was measured by endogenously labeling their protein component, apolipoprotein B.

RESULTS

In study 1, the conjugated estrogens at doses of 0.625 mg per day and 1.25 mg per day decreased the mean LDL cholesterol level by 15 percent (95 percent confidence interval, 11 to 19 percent; P less than 0.0001) and 19 percent (95 percent confidence interval, 15 to 23 percent; P less than 0.0001), respectively; increased the HDL cholesterol level by 16 percent (95 percent confidence interval, 12 to 20 percent; P less than 0.0001) and 18 percent (95 percent confidence interval, 14 to 22 percent; P less than 0.0001), respectively; and increased VLDL triglyceride levels by 24 percent (95 percent confidence interval, 8 to 40 percent; P less than 0.003) and 42 percent (95 percent confidence interval, 26 to 58 percent; P less than 0.0001), respectively. In study 2, oral estradiol increased the mean concentration of large VLDL apolipoprotein B by 30 +/- 10 percent (P = 0.05) by increasing its production rate by 82 +/- 18 percent (P less than 0.01). Most of this additional large VLDL was cleared directly from the circulation and was not converted to small VLDL or LDL. Oral estradiol reduced LDL cholesterol concentrations by 14 +/- 3 percent (P less than 0.005), because LDL catabolism increased by 36 +/- 7 percent (P less than 0.005). The oral estradiol increased the HDL cholesterol level by 15 +/- 2 percent (P less than 0.0001). Transdermal estradiol had no effect.

CONCLUSIONS

The postmenopausal use of oral estrogens in low doses favorably alters LDL and HDL levels that may protect women against atherosclerosis, while minimizing potentially adverse effects on triglyceride levels. The decrease in LDL levels results from accelerated LDL catabolism; the increase in triglyceride levels results from increased production of large, triglyceride-rich VLDL.

Menopause: advanced management strategies

Estrogen replacement therapy may offer significant benefits to nearly all postmenopausal women, especially those for whom the menopause occurred at an early age. Women at high risk for atherosclerosis, or who already have cardiovascular disease, may particularly benefit from estrogen use. The increased risk for endometrial and breast cancer seen with estrogen replacement therapy is low in comparison with its protective effect against cardiovascular disease. For women who cannot or choose not to take estrogens, etidronate may be of value in preventing osteoporotic fractures. For women many years beyond menopause who consume low-calcium diets, calcium supplementation should be recommended.

Interpersonal loss and self-mutilation

Self-mutilation was hypothesized to increase in frequency during periods of interpersonal loss in a treatment program for seriously disturbed adolescents. The study examined changes in the frequency of acts of self-mutilation, aggression, and running away for 32 teenagers who experienced interpersonal loss when staff members left employment. Data were collected for a 4-year period. Statistical findings indicated that the frequency of self-mutilation increased significantly during the time period of anticipated loss, 2 weeks prior to staff terminations. There was no significant increase in the frequency of self-mutilation immediately following the staff terminations. Also, there was no significant change in the rates of aggression or running away either before or after the loss events. It was concluded that the time of anticipated loss was the period of highest risk for these adolescents in terms of self-mutilative behavior.

Patterns of contagion in self-mutilation epidemics

Contagion of self-mutilation was studied in a treatment program for disturbed adolescents. Statistical analyses and a sociogram revealed that 1) episodes of contagion were significantly associated with specific pairs of subjects, and 2) a few subjects were identified as being at the center of most of the contagion activity.

Self-mutilation and contagion: an empirical test

Twenty-five subjects treated at a center for disturbed adolescents were observed over a 1-year period for signs of self-mutilative contagion. Statistical analysis confirmed that self-mutilation occurred in clusters throughout the year, suggesting that subjects imitated one another's behavior.

A community residence for severely disturbed adolescents: a cognitive-behavioral approach

A family-style, community-based program for severely disturbed adolescents uses a point-and-fine system that combines operant, modeling and cognitive-behavioral strategies.