Susan L. Hendrix

The Women's Health Initiative Observational Study: Baseline Characteristics of Participants and Reliability of Baseline Measures

The Women’s Health Initiative (WHI) Observational Study (OS) was established to explore the predictors and natural history of important causes of morbidity and mortality in postmenopausal women, and to serve as a secular control for the WHI Clinical Trial (CT). It enrolled 93,676 ethnically diverse women born in four different decades, from those who came of age in the depression-era, to the first members of the baby boom. Accordingly, this cohort reflects a wide range of socio-cultural influences on opportunities and health behaviors. OS participants will contribute longitudinal data on health status, risk exposures and disease events. The followup interval will be slightly shorter than that in the clinical trial, approximately 7 years. All OS women had a physical examination at baseline and 3 years. Additional data are obtained with annual mailed questionnaires. These forms explore risk exposures, health behaviors, and the prevalence of less common diseases to provide a comprehensive view of both classical and novel risk factors, as well as secular trends in the predictors of healthy aging and disease events. Because of its size, the OS will permit exploration of factors associated with less common diseases. This article describes the demographic, reproductive, dietary, and health characteristics of the OS women by eth-

Estrogen plus progestin and breast cancer incidence and mortality in postmenopausal women.

CONTEXT In the Womens Health Initiative randomized, placebo-controlled trial of estrogen plus progestin, after a mean intervention time of 5.6 (SD, 1.3) years (range, 3.7-8.6 years) and a mean follow-up of 7.9 (SD, 1.4) years, breast cancer incidence was increased among women who received combined hormone therapy. Breast cancer mortality among participants in the trial has not been previously reported. OBJECTIVE To determine the effects of therapy with estrogen plus progestin on cumulative breast cancer incidence and mortality after a total mean follow-up of 11.0 (SD, 2.7) years, through August 14, 2009. DESIGN, SETTING, AND PARTICIPANTS A total of 16,608 postmenopausal women aged 50 to 79 years with no prior hysterectomy from 40 US clinical centers were randomly assigned to receive combined conjugated equine estrogens, 0.625 mg/d, plus medroxyprogesterone acetate, 2.5 mg/d, or placebo pill. After the original trial completion date (March 31, 2005), reconsent was required for continued follow-up for breast cancer incidence and was obtained from 12,788 (83%) of the surviving participants. MAIN OUTCOME MEASURES Invasive breast cancer incidence and breast cancer mortality. RESULTS In intention-to-treat analyses including all randomized participants and censoring those not consenting to additional follow-up on March 31, 2005, estrogen plus progestin was associated with more invasive breast cancers compared with placebo (385 cases [0.42% per year] vs 293 cases [0.34% per year]; hazard ratio [HR], 1.25; 95% confidence interval [CI], 1.07-1.46; P = .004). Breast cancers in the estrogen-plus-progestin group were similar in histology and grade to breast cancers in the placebo group but were more likely to be node-positive (81 [23.7%] vs 43 [16.2%], respectively; HR, 1.78; 95% CI, 1.23-2.58; P = .03). There were more deaths directly attributed to breast cancer (25 deaths [0.03% per year] vs 12 deaths [0.01% per year]; HR, 1.96; 95% CI, 1.00-4.04; P = .049) as well as more deaths from all causes occurring after a breast cancer diagnosis (51 deaths [0.05% per year] vs 31 deaths [0.03% per year]; HR, 1.57; 95% CI, 1.01-2.48; P = .045) among women who received estrogen plus progestin compared with women in the placebo group. CONCLUSIONS Estrogen plus progestin was associated with greater breast cancer incidence, and the cancers are more commonly node-positive. Breast cancer mortality also appears to be increased with combined use of estrogen plus progestin. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00000611.

Breast Cancer after Use of Estrogen plus Progestin in Postmenopausal Women

BACKGROUND Following the release of the 2002 report of the Womens Health Initiative (WHI) trial of estrogen plus progestin, the use of menopausal hormone therapy in the United States decreased substantially. Subsequently, the incidence of breast cancer also dropped, suggesting a cause-and-effect relation between hormone treatment and breast cancer. However, the cause of this decrease remains controversial. METHODS We analyzed the results of the WHI randomized clinical trial--in which one study group received 0.625 mg of conjugated equine estrogens plus 2.5 mg of medroxyprogesterone acetate daily and another group received placebo--and examined temporal trends in breast-cancer diagnoses in the WHI observational-study cohort. Risk factors for breast cancer, frequency of mammography, and time-specific incidence of breast cancer were assessed in relation to combined hormone use. RESULTS In the clinical trial, there were fewer breast-cancer diagnoses in the group receiving estrogen plus progestin than in the placebo group in the initial 2 years of the study, but the number of diagnoses increased over the course of the 5.6-year intervention period. The elevated risk decreased rapidly after both groups stopped taking the study pills, despite a similar frequency of mammography. In the observational study, the incidence of breast cancer was initially about two times as high in the group receiving menopausal hormones as in the placebo group, but this difference in incidence decreased rapidly in about 2 years, coinciding with year-to-year reductions in combined hormone use. During this period, differences in the frequency of mammography between the two groups were unchanged. CONCLUSIONS The increased risk of breast cancer associated with the use of estrogen plus progestin declined markedly soon after discontinuation of combined hormone therapy and was unrelated to changes in frequency of mammography.

Effects of Conjugated Equine Estrogen on Stroke in the Women’s Health Initiative

Background— The Women’s Health Initiative (WHI) Estrogen Alone trial assessed the balance of benefits and risks of hormone use in healthy postmenopausal women. The trial was stopped prematurely because there was no benefit for coronary heart disease and an increased risk of stroke. This report provides a thorough analysis of the stroke finding using the final results from the completed trial database. Methods and Results— The WHI Estrogen Alone hormone trial is a multicenter, double-blind, placebo-controlled, randomized clinical trial in 10 739 women aged 50 to 79 years who were given daily conjugated equine estrogen (CEE; 0.625 mg; n=5310) or placebo (n=5429). During an average follow-up of 7.1 years, there were 168 strokes in the CEE group and 127 in the placebo group; 80.3% of strokes were ischemic. For all stroke the intention-to-treat hazard ratio [HR] (95% CI) for CEE versus placebo was 1.37 (1.09 to 1.73). The HR (95% CI) was 1.55 (1.19 to 2.01) for ischemic stroke and 0.64 (0.35, 1.18) for hemorrhagic stroke. The HRs indicate excess risk of ischemic stroke was apparent in all categories of baseline stroke risk, including younger and more recently menopausal women and in women with prior or current use of statins or aspirin. Conclusions— CEE increases the risk of ischemic stroke in generally healthy postmenopausal women. The excess risk appeared to be present in all subgroups of women examined, including younger and more recently menopausal women. There was no convincing evidence to suggest that CEE had an effect on the risk of hemorrhagic stroke.

Oral Bisphosphonate Use and Breast Cancer Incidence in Postmenopausal Women

PURPOSE Emerging clinical evidence suggests intravenous bisphosphonates may inhibit breast cancer while oral bisphosphonates have received limited evaluation regarding breast cancer influence. PATIENTS AND METHODS The association between oral bisphosphonate use and invasive breast cancer was examined in postmenopausal women enrolled onto the Womens Health Initiative (WHI). We compared a published hip fracture prediction model, which did not incorporate bone mineral density (BMD), with total hip BMD in 10,418 WHI participants who had both determinations. To adjust for potential BMD difference based on bisphosphonate use, the hip fracture prediction score was included in multivariant analyses as a BMD surrogate. RESULTS Of the 154,768 participants, 2,816 were oral bisphosphonate users at entry (90% alendronate, 10% etidronate). As calculated hip fracture risk score was significantly associated with both BMD (regression line = 0.79 to 0.0478 log predicted fracture; P < .001; r = 0.43) and breast cancer incidence (P = .03), this variable was incorporated into regression analyses to adjust for BMD difference between users and nonusers of bisphopshonate. After 7.8 mean years of follow-up (standard deviation, 1.7), invasive breast cancer incidence was lower in bisphosphonate users (hazard ratio [HR], 0.68; 95% CI, 0.52 to 0.88; P < .01) as was incidence of estrogen receptor (ER) -positive invasive cancers (HR, 0.70; 95% CI, 0.52 to 0.94, P = .02). A similar but not significant trend was seen for ER-negative invasive cancers. The incidence of ductal carcinoma in situ was higher in bisphosphonate users (HR, 1.58; 95% CI, 1.08 to 2.31; P = .02). CONCLUSION Oral bisphosphonate use was associated with significantly lower invasive breast cancer incidence, suggesting bisphosphonates may have inhibiting effects on breast cancer.

Cross-sectional geometry, bone strength, and bone mass in the proximal femur in black and white postmenopausal women

Osteoporosis is characterized by both a low bone mass and a disruption of the architectural arrangement of bone tissue, leading to decreased skeletal strength and increased fracture risk. Although there are well‐known ethnic differences in bone mass and fracture risk, little is known about possible ethnic differences in bone structure. Therefore, we studied cross‐sectional geometry in the hip in a sample of postmenopausal black and white women in order to investigate ethnic differences that might contribute to differences in bone strength and ultimately hip fracture risk. We recruited 371 postmenopausal black and white women who were entering the Womens Health Initiative (WHI) clinical trials in Detroit. Bone density measurements of the proximal femur were done by dual‐energy X‐ray absorptiometry (DXA) using a Hologic 1000 Plus bone densitometer. The DXA data were used for hip structure analysis, which treats the entire proximal femur as a continuous curved beam from the proximal shaft to the femoral neck. This permits the analysis of cross‐sectional geometric properties in two narrow regions corresponding to thin (5 mm) cross‐sectional slabs seen on edge. The results indicate significant ethnic differences in bone density, cross‐sectional geometry, and dimensional variables. Specifically, the black women have a significantly higher bone density in both locations (10.1% and 4.1% for the neck and shaft, respectively); greater cross‐sectional geometric properties in the neck (ranging from 6.1% to 11.6%), but a smaller endocortical diameter in the neck (3.6%). There are fewer significant differences in cross‐sectional geometry in the shaft location. Our data suggest that the spatial distribution of bone is arranged in the femoral neck to resist greater loading in black women compared with white women.

Resting heart rate as a low tech predictor of coronary events in women: prospective cohort study

Objective To evaluate resting heart rate as an independent predictor of cardiovascular risk in women. Design Prospective cohort study. Setting The Women’s Health Initiative was undertaken at 40 research clinics in the United States. Participants 129 135 postmenopausal women. Main outcome measure Clinical cardiovascular events. Results During a mean of 7.8 (SD 1.6) years of follow up, 2281 women were identified with myocardial infarction or coronary death and 1877 with stroke. We evaluated associations between resting heart rate and cardiovascular events in Cox regression models adjusted for multiple covariates. Higher resting heart rate was independently associated with coronary events (hazard ratio 1.26, 95% confidence interval 1.11 to 1.42 for highest [>76 beats per minute] v lowest quintile [≤62 beats per minute]; P=0.001), but not with stroke. The relation between heart rate and coronary events did not differ between white women and women from other ethnic groups (P for interaction=0.45) or between women with and without diabetes (P for interaction=0.31), but it was stronger in women aged 50-64 at baseline than in those aged 65-79 (P for interaction=0.009). Conclusion Resting heart rate, a low tech and inexpensive measure of autonomic tone, independently predicts myocardial infarction or coronary death, but not stroke, in women. Trial registration ClinicalTrials.gov NCT00000611.

Calcium/vitamin D supplementation and coronary artery calcification in the Women's Health Initiative.

Objective:Coronary artery calcified plaque is a marker for atheromatous plaque burden and predicts future risk of cardiovascular events. The relationship between calcium plus vitamin D (calcium/D) supplementation and coronary artery calcium (CAC) has not been previously assessed in a randomized trial setting. We compared CAC scores after trial completion between women randomized to calcium/vitamin D supplementation and women randomized to placebo. Methods:In an ancillary substudy of women randomized to calcium carbonate (1,000 mg of elemental calcium daily) plus vitamin D3 (400 IU daily) or placebo, nested within the Womens Health Initiative trial of estrogen among women who underwent hysterectomy, we measured CAC with cardiac CT in 754 women aged 50 to 59 years at randomization. Imaging for CAC was performed at 28 of 40 centers after a mean of 7 years of treatment, and scans were read centrally. CAC scores were measured by a central reading center with masking to randomization assignments. Results:Posttrial CAC measurements were similar in women randomized to calcium/D supplementation and those receiving placebo. The mean CAC score was 91.6 for women receiving calcium/D and 100.5 for women receiving placebo (rank test P value = 0.74). After adjustment for coronary risk factors, multivariate odds ratios for increasing CAC score cutpoints (CAC >0, ≥10, and ≥100) for calcium/D versus placebo were 0.92 (95% CI, 0.64-1.34), 1.29 (0.88-1.87), and 0.90 (0.56-1.44), respectively. Corresponding odds ratios among women with a 50% or higher adherence to study pills and for higher levels of CAC (>300) were similar. Conclusions:Treatment with moderate doses of calcium plus vitamin D3 did not seem to alter coronary artery calcified plaque burden among postmenopausal women. Whether higher or lower doses would affect this outcome remains uncertain.

Effect of Weight Change on Natural History of Pelvic Organ Prolapse

OBJECTIVE: To evaluate the relationship between change in weight and pelvic organ prolapse (POP) progression/regression in women during a 5-year period. METHODS: Postmenopausal women with uteri (N=16,608), ages 50 to 79, who were enrolled in the Women’s Health Initiative (WHI) Estrogen plus Progestin Clinical Trial between 1993 and 1998 were included in this secondary analysis. Baseline pelvic examination, repeated annually, assessed uterine prolapse, cystocele, and rectocele using the WHI Prolapse Classification System. Statistical analyses included univariate and multiple logistic regression methods. RESULTS: During the 5-year time period, the majority of women (9,251, 55.7%) gained weight (mean 4.43 kg, ±5.95 kg), and the overall rate of prolapse (WHI Prolapse Classification System: grades 1–3) increased from 40.9% at baseline to 43.8% at year 5 of evaluation. Controlling for age, parity, race, and other health/physical variables, being overweight (body mass index [BMI] between 25 and 29.9) or obese (BMI of at least 30) at baseline was associated with progression in cystocele, rectocele, and uterine prolapse compared with women with healthy BMIs (BMI is calculated as weight (kg)/[height (m)]2). Specifically, the risk of prolapse progression in overweight and obese women as compared with the participants with healthy BMIs increased by 32% and 48% for cystocele, by 37% and 58% for rectocele, and by 43% and 69% for uterine prolapse, respectively. Adjusting for women with prolapse at baseline and baseline BMI, a 10% weight change was associated with minimal change in overall POP. Specifically, a 10% weight loss was associated with a borderline worsening of uterine prolapse (odds ratio [OR] 0.93, 95% confidence interval [CI] 0.88–0.97) and a minimal regression of cystocele (OR 1.03, 95% CI 1.00–1.05) and rectocele (OR 1.04, 95% CI 1.01–1.07). CONCLUSION: Being overweight or obese is associated with progression of POP. Weight loss does not appear to be significantly associated with regression of POP, suggesting that damage to the pelvic floor related to weight gain might be irreversible. LEVEL OF EVIDENCE: II

Douching and endometritis: results from the PID evaluation and clinical health (PEACH) study.

Background Douching has been related to risk of pelvic inflammatory disease (PID). Goal To examine the association between douching and PID in a large, multicenter, clinical trial of PID after adjustment for race/ethnicity. Study Design Interviews were conducted with 654 women who had signs and symptoms of PID. Vaginal Gram stains and upper genital tract pathology/cultures were obtained from all the women. Women with evidence of plasma cell endometritis and/or gonococcal or chlamydial upper genital tract infections were compared with women who had neither endometritis nor upper genital tract infection. Results Women with endometritis or upper genital tract infection were more likely to have douched more than once a month or within 6 days of enrollment than women who never douched. These associations remained after adjustment for confounding factors, after analysis of black women only; and among women with normal or intermediate vaginal flora but not bacterial vaginosis. Conclusion Among a predominantly black group of women with clinical PID, frequent and recent douching was associated with endometritis and upper genital tract infection.