Rebecca J. Rodabough

Oestrogen plus progestin and lung cancer in postmenopausal women (Women's Health Initiative trial): a post-hoc analysis of a randomised controlled trial.

BACKGROUND In the post-intervention period of the Womens Health Initiative (WHI) trial, women assigned to treatment with oestrogen plus progestin had a higher risk of cancer than did those assigned to placebo. Results also suggested that the combined hormone therapy might increase mortality from lung cancer. To assess whether such an association exists, we undertook a post-hoc analysis of lung cancers diagnosed in the trial over the entire follow-up period. METHODS The WHI study was a randomised, double-blind, placebo-controlled trial undertaken in 40 centres in the USA. 16 608 postmenopausal women aged 50-79 years with an intact uterus were randomly assigned by a computerised, stratified, permuted block algorithm to receive a once-daily tablet of 0.625 mg conjugated equine oestrogen plus 2.5 mg medroxyprogesterone acetate (n=8506) or matching placebo (n=8102). We assessed incidence and mortality rates for all lung cancer, small-cell lung cancer, and non-small-cell lung cancer by use of data from treatment and post-intervention follow-up periods. Analysis was by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00000611. FINDINGS After a mean of 5.6 years (SD 1.3) of treatment and 2.4 years (0.4) of additional follow-up, 109 women in the combined hormone therapy group had been diagnosed with lung cancer compared with 85 in the placebo group (incidence per year 0.16%vs 0.13%; hazard ratio [HR] 1.23, 95% CI 0.92-1.63, p=0.16). 96 women assigned to combined therapy had non-small-cell lung cancer compared with 72 assigned to placebo (0.14%vs 0.11%; HR 1.28, 0.94-1.73, p=0.12). More women died from lung cancer in the combined hormone therapy group than in the placebo group (73 vs 40 deaths; 0.11%vs 0.06%; HR 1.71, 1.16-2.52, p=0.01), mainly as a result of a higher number of deaths from non-small-cell lung cancer in the combined therapy group (62 vs 31 deaths; 0.09%vs 0.05%; HR 1.87, 1.22-2.88, p=0.004). Incidence and mortality rates of small-cell lung cancer were similar between groups. INTERPRETATION Although treatment with oestrogen plus progestin in postmenopausal women did not increase incidence of lung cancer, it increased the number of deaths from lung cancer, in particular deaths from non-small-cell lung cancer. These findings should be incorporated into risk-benefit discussions with women considering combined hormone therapy, especially those with a high risk of lung cancer. FUNDING National Heart, Lung and Blood Institute, National Institutes of Health.

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.

Oophorectomy vs Ovarian Conservation With Hysterectomy: Cardiovascular Disease, Hip Fracture, and Cancer in the Women's Health Initiative Observational Study

BACKGROUND Elective bilateral salpingo-oophorectomy (BSO) is routinely performed with hysterectomy for benign conditions despite conflicting data on long-term outcomes. METHODS This is a prospective cohort of 25 448 postmenopausal women aged 50 to 79 years enrolled in the Womens Health Initiative Observational Study who had a history of hysterectomy and BSO (n = 14 254 [56.0%]) or hysterectomy with ovarian conservation (n = 11 194 [44.0%]) and no family history of ovarian cancer. Multivariable Cox proportional hazards regression models were used to examine the effect of BSO on incident cardiovascular disease, hip fracture, cancer, and death. RESULTS Current or past use of estrogen and/or progestin was common irrespective of BSO status (78.6% of cohort). In multivariable analyses, BSO was not associated with an increased risk of fatal and nonfatal coronary heart disease (hazard ratio, 1.00 [95% confidence interval, 0.85-1.18]), coronary artery bypass graft/percutaneous transluminal coronary angioplasty (0.95 [0.82-1.10]), stroke (1.04 [0.87-1.24]), total cardiovascular disease (0.99 [0.91-1.09]), hip fracture (0.83 [0.63-1.10]), or death (0.98 [0.87-1.10]). Bilateral salpingo-oophorectomy decreased incident ovarian cancer (0.02% in the BSO group; 0.33% in the ovarian conservation group; number needed to treat, 323) during a mean (SD) follow-up of 7.6 (1.6) years, but there were no significant associations for breast, colorectal, or lung cancer. CONCLUSIONS In this large prospective cohort study, BSO decreased the risk of ovarian cancer compared with hysterectomy and ovarian conservation, but incident ovarian cancer was rare in both groups. Our findings suggest that BSO may not have an adverse effect on cardiovascular health, hip fracture, cancer, or total mortality compared with hysterectomy and ovarian conservation.

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.

Lung cancer among postmenopausal women treated with estrogen alone in the women's health initiative randomized trial

BACKGROUND In the Womens Health Initiative (WHI) randomized controlled trial, use of estrogen plus progestin increased lung cancer mortality. We conducted post hoc analyses in the WHI trial evaluating estrogen alone to determine whether use of conjugated equine estrogen without progestin had a similar adverse influence on lung cancer. METHODS The WHI study is a randomized, double-blind, placebo-controlled trial conducted in 40 centers in the United States. A total of 10 739 postmenopausal women aged 50-79 years who had a previous hysterectomy were randomly assigned to receive a once-daily 0.625-mg tablet of conjugated equine estrogen (n = 5310) or matching placebo (n = 5429). Incidence and mortality rates for all lung cancers, small cell lung cancers, and non-small cell lung cancers in the two randomization groups were compared by use of hazard ratios (HRs) and 95% confidence intervals (CIs) that were estimated from Cox proportional hazards regression analyses. Analyses were by intention to treat, and all statistical tests were two-sided. RESULTS After a mean of 7.9 years (standard deviation = 1.8 years) of follow-up, 61 women in the hormone therapy group were diagnosed with lung cancer compared with 54 in the placebo group (incidence of lung cancer per year = 0.15% vs 0.13%, respectively; HR of incidence = 1.17, 95% CI = 0.81 to 1.69, P = .39). Non-small cell lung cancers were of comparable number, stage, and grade in both groups. Deaths from lung cancer did not differ between the two groups (34 vs 33 deaths in estrogen and placebo groups, respectively; HR of death = 1.07, 95% CI = 0.66 to 1.72, P = .79). CONCLUSION Unlike use of estrogen plus progestin, which increased deaths from lung cancer, use of conjugated equine estrogen alone did not increase incidence or death from lung cancer.

Genome-wide association study identifies multiple loci associated with bladder cancer risk

Candidate gene and genome-wide association studies (GWAS) have identified 11 independent susceptibility loci associated with bladder cancer risk. To discover additional risk variants, we conducted a new GWAS of 2422 bladder cancer cases and 5751 controls, followed by a meta-analysis with two independently published bladder cancer GWAS, resulting in a combined analysis of 6911 cases and 11 814 controls of European descent. TaqMan genotyping of 13 promising single nucleotide polymorphisms with P < 1 × 10(-5) was pursued in a follow-up set of 801 cases and 1307 controls. Two new loci achieved genome-wide statistical significance: rs10936599 on 3q26.2 (P = 4.53 × 10(-9)) and rs907611 on 11p15.5 (P = 4.11 × 10(-8)). Two notable loci were also identified that approached genome-wide statistical significance: rs6104690 on 20p12.2 (P = 7.13 × 10(-7)) and rs4510656 on 6p22.3 (P = 6.98 × 10(-7)); these require further studies for confirmation. In conclusion, our study has identified new susceptibility alleles for bladder cancer risk that require fine-mapping and laboratory investigation, which could further understanding into the biological underpinnings of bladder carcinogenesis.

Obesity in relation to endometrial cancer risk and disease characteristics in the Women's Health Initiative.

OBJECTIVE Obesity increases endometrial cancer risk, yet its impact on disease stage and grade is unclear. We prospectively examined the effects of body mass index (BMI) and waist-to-hip ratio (WHR) on incidence, stage, and grade of endometrial cancer. METHODS We studied 86937 postmenopausal women enrolled in the Womens Health Initiative. Height, weight, and waist and hip circumference were measured at baseline. Endometrial cancer cases were adjudicated by trained physicians and pathology reports were used to determine stage and grade. Cox proportional hazards models generated hazard ratios (HR) for associations between BMI and WHR and risk of endometrial cancer. Logistic regression was used to evaluate associations between BMI and WHR and disease stage and grade. RESULTS During a mean 7.8 (standard deviation 1.6) years of follow-up, 806 women were diagnosed with endometrial cancer. Although incidence was higher among Whites, stage and grade were similar between Whites and Blacks. Elevated BMI (HR 1.76, 95% confidence interval [CI] 1.41-2.19) and WHR (HR 1.33, 95% CI 1.04-1.70) increased endometrial cancer risk when comparing women in the highest and lowest categories. No associations were observed between BMI or WHR and disease stage or grade. CONCLUSIONS Obesity increases endometrial cancer risk independent of other factors but is not associated with stage or grade of disease. These findings support and validate previous reports. Future research should evaluate the impact of obesity on racial disparities in endometrial cancer survival.

Calcium plus vitamin D supplementation and health outcomes five years after active intervention ended: the Women's Health Initiative.

BACKGROUND Clinical outcomes of the Womens Health Initiative (WHI) calcium plus vitamin D supplementation trial have been reported during 7.0 years of active intervention. We now report outcomes 4.9 years after the intervention stopped and cumulative findings. METHODS Postmenopausal women (N=36,282) were randomized; postintervention follow-up continued among 29,862 (86%) of surviving participants. Primary outcomes were hip fracture and colorectal cancer. Breast cancer, all cancers, cardiovascular disease (CVD), and total mortality were predetermined major study outcomes. RESULTS Hip fracture incidence was comparable in the supplement and the placebo groups, postintervention hazard ratio (HR)=0.95, 95% confidence interval (95% CI: 0.78, 1.15) and overall HR=0.91 (95% CI: 0.79, 1.05). Overall, colorectal cancer incidence did not differ between randomization groups, HR=0.95 (95% CI: 0.80, 1.13). Throughout, there also was no difference in invasive breast cancer, CVD, and all-cause mortality between groups. In subgroup analyses, the invasive breast cancer effect varied by baseline vitamin D intake (p=0.03 for interaction). Women with vitamin D intakes >600 IU/d, had an increased risk of invasive breast cancer, HR=1.28 (95% CI; 1.03, 1.60). Over the entire study period, in post hoc analyses, the incidence of vertebral fractures, HR=0.87 (95% CI: 0.76, 0.98) and in situ breast cancers, HR=0.82 (95% CI: 0.68, 0.99) were lower among women randomized to supplementation. CONCLUSION After an average of 11 years, calcium and vitamin D supplementation did not decrease hip fracture or colorectal cancer incidence. Exploratory analyses found lower vertebral fracture and in situ breast cancer incidence in the supplement users. There was no effect on CVD or all-cause mortality.

Estrogen Plus Progestin and the Risk of Peripheral Arterial Disease The Women’s Health Initiative

Background—Observational studies have reported less frequent carotid atherosclerosis in healthy women taking postmenopausal hormone therapy. Estrogen with progestin did not reduce peripheral arterial events among women with preexisting coronary heart disease. This analysis evaluates clinical peripheral arterial disease among generally healthy women in the Women’s Health Initiative randomized trial of estrogen plus progestin. Methods and Results—The Estrogen Plus Progestin trial assigned 16 608 postmenopausal women, mean age 63.3±7.1 years, to daily conjugated estrogens (0.625 mg) with medroxyprogesterone acetate (2.5 mg) or placebo and documented health outcomes over an average of 5.6 years of follow-up. Hospitalization for peripheral arterial disease was infrequent, with annualized rates of 0.08%, 0.06%, and 0.02% for carotid disease, lower extremity arterial disease, and abdominal aortic aneurysm, respectively. The incidence of peripheral arterial events did not differ between treatment groups (hazard ratio [HR] 0.89, 95% confidence interval 0.63, 1.25). The risk was slightly greater among women assigned to active estrogen with progestin in years 1 (HR 1.33) and 2 (HR 1.27), and was slightly lower in later years (HR 0.85 and 0.87 in years 5 and ≥6). Among adherent participants, the hazard ratio for peripheral arterial events was 1.23 (95% confidence interval 0.79, 1.91) over the 5.6 years of follow up. Subgroup analysis identified no significant interactions between estrogen with progestin and baseline characteristics with regard to peripheral arterial disease risk. Conclusions—Among generally healthy postmenopausal women, conjugated estrogens with progestin did not confer protection against peripheral arterial disease.

Changes in food sources of dietary fat in response to an intensive low-fat dietary intervention: Early results from the Women's Health Initiative

OBJECTIVE To evaluate changes in food sources of dietary fat made by participants in the Womens Health Initiative Low-Fat Dietary Modification Trial. DESIGN This study compares sources of dietary fat intake, estimated by a food frequency questionnaire, between intervention and control participants at baseline, 1 year (year 1) and 2 years (year 2) after randomization. The outcome measure was intake of fat in grams per day. Results are given on consumption of fat from six food groups and the intervention effect, defined as mean change in the intervention group minus the change in controls, controlling for baseline fat intake. PARTICIPANTS 5,004 intervention and 7,426 control postmenopausal women in 40 clinical centers across the United States. RESULTS At baseline, the major sources of fat were added fats, such as butter, oils, and salad dressings (25%); meats (21%); and desserts (13%). From baseline to year 1, the intervention group reduced fat by 24.3 g/day compared with the control group. Reductions came primarily from added fats (9.1 g/day), meats (4.6 g/day), and desserts (3.9 g/day). White people reduced added fats more than other race/ethnicity groups did, white and Hispanic people were more likely to reduce fat intake from milk and cheese compared with other groups, and Hispanics reduced fat from mixed dishes more than did other race/ethnicity groups (P<.05 for all). APPLICATIONS/CONCLUSIONS These data indicate that women in the Womens Health Initiative dietary change intervention made substantial changes in food choices. These results can facilitate future low-fat interventions, and also offer clinical applications, by identifying foods that may be refractory to change.