Bilateral oophorectomy is not associated with increased mortality: the California Teachers Study

Menopause, hysterectomy, menopausal hormone therapy and cause-specific mortality: cohort study of UK Biobank participants

STUDY QUESTION

What is the association between menopausal hormone therapy (MHT) and cause-specific mortality?

SUMMARY ANSWER

Self-reported MHT use following early natural menopause, surgical menopause or premenopausal hysterectomy is associated with a lower risk of breast cancer mortality and is not consistently associated with the risk of mortality from cardiovascular disease or other causes.

WHAT IS KNOWN ALREADY

Evidence from the Women's Health Initiative randomized controlled trials showed that the use of estrogen alone is not associated with the risk of cardiovascular mortality and is associated with a lower risk of breast cancer mortality, but evidence from the Million Women Study showed that use of estrogen alone is associated with a higher risk of breast cancer mortality.

STUDY DESIGN, SIZE, DURATION

Cohort study (the UK Biobank), 178 379 women, recruited in 2006-2010.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Postmenopausal women who had reported age at menopause (natural or surgical) or hysterectomy, and information on MHT and cause-specific mortality. Age at natural menopause, age at surgical menopause, age at hysterectomy and MHT were exposures of interest. Natural menopause was defined as spontaneous cessation of menstruation for 12 months with no previous hysterectomy or oophorectomy. Surgical menopause was defined as the removal of both ovaries prior to natural menopause. Hysterectomy was defined as removal of the uterus before natural menopause without bilateral oophorectomy. The study outcome was cause-specific mortality.

MAIN RESULTS AND THE ROLE OF CHANCE

Among the 178 379 women included, 136 790 had natural menopause, 17 569 had surgical menopause and 24 020 had hysterectomy alone. Compared with women with natural menopause at the age of 50-52 years, women with natural menopause before 40 years (hazard ratio (HR): 2.38, 95% CI: 1.64, 3.45) or hysterectomy before 40 years (HR: 1.60, 95% CI: 1.23, 2.07) had a higher risk of cardiovascular mortality but not cancer mortality. MHT use was associated with a lower risk of breast cancer mortality following surgical menopause before 45 years (HR: 0.17, 95% CI: 0.08, 0.36), at 45-49 years (HR: 0.15, 95% CI: 0.07, 0.35) or at ≥50 years (HR: 0.28, 95% CI: 0.13, 0.63), and the association between MHT use and the risk of breast cancer mortality did not differ by MHT use duration (<6 or 6-20 years). MHT use was also associated with a lower risk of breast cancer mortality following natural menopause before 45 years (HR: 0.59, 95% CI: 0.36, 0.95) or hysterectomy before 45 years (HR: 0.49, 95% CI: 0.32, 0.74).

LIMITATIONS, REASONS FOR CAUTION

Self-reported data on age at natural menopause, age at surgical menopause, age at hysterectomy and MHT.

WIDER IMPLICATIONS OF THE FINDINGS

The current international guidelines recommend women with early menopause to use MHT until the average age at menopause. Our findings support this recommendation.

STUDY FUNDING/COMPETING INTEREST(S)

This project is funded by the Australian National Health and Medical Research Council (NHMRC) (grant numbers APP1027196 and APP1153420). G.D.M. is supported by NHMRC Principal Research Fellowship (APP1121844), and M.H. is supported by an NHMRC Investigator Grant (APP1193838). There are no competing interests.

TRIAL REGISTRATION NUMBER

N/A.

Effect of risk-reducing salpingo-oophorectomy on sex steroid hormone serum levels among postmenopausal women: an NRG Oncology/Gynecologic Oncology Group study

BACKGROUND

Risk-reducing salpingo-oophorectomy is an effective ovarian cancer risk reduction strategy. However, bilateral oophorectomy has also been associated with increased long-term nonneoplastic sequelae, effects suggested to be mediated through reductions in systemic sex steroid hormone levels. Currently, it is unclear whether the postmenopausal ovary contributes to the systemic hormonal milieu or whether postmenopausal ovarian volume or other factors, such as body mass index and age, affect systemic hormone levels.

OBJECTIVE

We examined the impact of oophorectomy on sex steroid hormone levels in postmenopausal women. Furthermore, we explored how well ovarian volume measured by transvaginal ultrasound correlated with direct ovarian measures obtained during surgical pathology evaluation and investigated the association between hormone levels and ovarian volumes.

STUDY DESIGN

Postmenopausal women who underwent risk-reducing salpingo-oophorectomy (180 cases) or ovarian cancer screening (38 controls) enrolled in an international, prospective study of risk-reducing salpingo-oophorectomy and risk of ovarian cancer algorithm-based screening among women at increased risk of ovarian cancer (Gynecologic Oncology Group-0199) were included in this analysis. Controls were frequency matched to the cases on age at menopause, age at study entry, and time interval between blood draws. Ovarian volume was calculated using measurements obtained from transvaginal ultrasound in both cases and controls and measurements recorded in surgical pathology reports from cases. Serum hormone levels of testosterone, androstenedione, androstenediol, dihydrotestosterone, androsterone, dehydroepiandrosterone, estrone, estradiol, and sex hormone-binding globulin were measured at baseline and follow-up. Spearman correlation coefficients were used to compare ovarian volumes as measured on transvaginal ultrasound and pathology examinations. Correlations between ovarian volumes by transvaginal ultrasound and measured hormone levels were examined using linear regression models. All models were adjusted for age. Paired t tests were performed to evaluate individual differences in hormone levels before and after risk-reducing salpingo-oophorectomy.

RESULTS

Ovarian volumes measured by transvaginal ultrasound were only moderately correlated with those reported on pathology reports (Spearman rho [ρ]=0.42). The median time interval between risk-reducing salpingo-oophorectomy and follow-up for the cases was 13.3 months (range, 6.0-19.3), and the median time interval between baseline and follow-up for the controls was 12.7 months (range, 8.7-13.4). Sex steroid levels decreased with age but were not correlated with transvaginal ultrasound ovarian volume, body mass index, or time since menopause. Estradiol levels were significantly lower after risk-reducing salpingo-oophorectomy (percentage change, -61.9 post-risk-reducing salpingo-oophorectomy vs +15.2 in controls; P=.02), but no significant differences were seen for the other hormones.

CONCLUSION

Ovarian volumes measured by transvaginal ultrasound were moderately correlated with volumes directly measured on pathology specimens and were not correlated with sex steroid hormone levels in postmenopausal women. Estradiol was the only hormone that declined significantly after risk-reducing salpingo-oophorectomy. Thus, it remains unclear whether the limited post-risk-reducing salpingo-oophorectomy changes in sex steroid hormones among postmenopausal women impact long-term adverse outcomes.

Cost-effectiveness Analysis of Genotype-Specific Surveillance and Preventive Strategies for Gynecologic Cancers Among Women With Lynch Syndrome

IMPORTANCE

With the expansion of multigene testing for cancer susceptibility, Lynch syndrome (LS) has become more readily identified among women. The condition is caused by germline pathogenic variants in DNA mismatch repair genes (ie, MLH1, MSH2, MSH6, and PMS2) and is associated with high but variable risks of endometrial and ovarian cancers based on genotype. However, current guidelines on preventive strategies are not specific to genotypes.

OBJECTIVE

To assess the cost-effectiveness of genotype-specific surveillance and preventive strategies for LS-associated gynecologic cancers, including a novel, risk-reducing surgical approach associated with decreased early surgically induced menopause.

DESIGN, SETTING, AND PARTICIPANTS

This economic evaluation developed a cohort-level Markov simulation model of the natural history of LS-associated gynecologic cancer for each gene, among women from ages 25 to 75 years or until death from a health care perspective. Age was varied at hysterectomy and bilateral salpingo-oophorectomy (hyst-BSO) and at surveillance initiation, and a 2-stage surgical approach (ie, hysterectomy and salpingectomy at age 40 years and delayed oophorectomy at age 50 years [hyst-BS]) was included. Extensive 1-way and probabilistic sensitivity analyses were performed.

INTERVENTIONS

Hyst-BSO at ages 35 years, 40 years, or 50 years with or without annual surveillance beginning at age 30 years or 35 years or hyst-BS at age 40 years with oophorectomy delayed until age 50 years.

MAIN OUTCOMES AND MEASURES

Incremental cost-effectiveness ratio (ICER) between management strategies within an efficiency frontier.

RESULTS

For women with MLH1 and MSH6 variants, the optimal strategy was the 2-stage approach, with respective ICERs of $33 269 and $20 008 compared with hyst-BSO at age 40 years. Despite being cost-effective, the 2-stage approach was associated with increased cancer incidence and mortality compared with hyst-BSO at age 40 years for individuals with MLH1 variants (incidence: 7.76% vs 3.84%; mortality: 5.74% vs 2.55%) and those with MSH6 variants (incidence: 7.24% vs 4.52%; mortality: 5.22% vs 2.97%). Hyst-BSO at age 40 years was optimal for individuals with MSH2 variants, with an ICER of $5180 compared with hyst-BSO at age 35 years, and was associated with 4.42% cancer incidence and 2.97% cancer mortality. For individuals with PMS2 variants, hyst-BSO at age 50 years was optimal and all other strategies were dominated; hyst-BSO at age 50 years was associated with an estimated cancer incidence of 0.68% and cancer mortality of 0.29%.

CONCLUSIONS AND RELEVANCE

These findings suggest that gene-specific preventive strategies for gynecologic cancers in LS may be warranted and support hyst-BSO at age 40 years for individuals with MSH2 variants. For individuals with MLH1 and MSH6 variants, these findings suggest that a novel 2-stage surgical approach with delayed oophorectomy may be an alternative to hyst-BSO at age 40 years to avoid early menopause, and for individuals with PMS2 variants, the findings suggest that hyst-BSO may be delayed until age 50 years.

Non-steroidal Anti-inflammatory Drug Use and Risk of Age-Related Macular Degeneration in the California Teachers Study

Purpose

The aim of this study was to examine whether use of regular aspirin and/or other non-steroidal anti-inflammatory drugs (NSAIDs) is associated with the development of age-related macular degeneration (AMD).

Methods

In the California Teachers Study cohort (N = 88,481) we identified diagnoses of AMD up to December 31, 2012 by linkage to statewide hospital discharge records. Aspirin, ibuprofen, other NSAIDs, and acetaminophen use and comprehensive risk factor information were collected via self-administered questionnaires at baseline in 1995–1996 and a follow-up questionnaire in 2005–2006. We employed Cox proportional hazard regression to model AMD risk.

Results

We did not find any associations between AMD and frequency and duration of aspirin or ibuprofen use reported at baseline. In the subsample with more specific information on medication use, we observed a 20% decrease in risk of AMD among low-dose aspirin users (HR 0.81, 95% CI 0.70–0.95) and a 55% decrease among cyclooxygenase-2 (COX-2) inhibitor users (HR 0.45, 95% CI 0.26–0.78) during 6.3 years of average follow-up.

Conclusion

The decrease in risk of intermediate- or late-stage AMD among women who reported regular use of low-dose aspirin or specific COX-2 inhibitors suggests a possible protective role for medications with COX-2 inhibitory properties or aspirin at doses used for cardiovascular disease prevention.

Association between rice consumption and risk of cancer incidence in the California Teachers Study

PURPOSE

We evaluated the contribution of rice intake, a source of dietary arsenic, to cancer risk in a population of women with likely low arsenic exposure from drinking water and variable rice intake who participated in the California Teachers Study.

METHODS

Rice consumption was categorized into quartiles (< 9.6, 9.7-15.6, 15.7-42.7, and ≥ 42.8 g/day). Multivariable-adjusted hazard ratios and 95% confidence intervals (95% CI) for incident cancer were estimated comparing rice consumption categories with bladder, breast, kidney, lung, and pancreatic cancer, with progressive adjustment for age, total calories, BMI, race, smoking status, physical activity, and cancer-specific covariates.

RESULTS

The number of breast, lung, pancreatic, bladder, and kidney cancer cases was 7,351; 1,100; 411; 344; and 238, respectively. The adjusted hazard ratios (95% CI) comparing the highest versus lowest rice intake quartiles were 1.07 (1.00-1.15); 0.87 (0.72-1.04); 0.95 (0.66-1.37); 1.11 (0.81-1.52) and 1.07 (0.72-1.59) for breast, lung, pancreatic, bladder, and kidney cancers, respectively. Results were consistent when rice was modeled as a continuous variable and in analyses stratified by smoking status.

CONCLUSION

Rice consumption was not associated with risk of kidney, lung or pancreatic cancer, except maybe a small excess risk for breast cancer and a small non-significant excess risk for bladder cancer, comparing the highest versus lowest quartile of rice intake. Due to lower consumption patterns in this cohort, future studies should involve populations for which rice is a staple food and use of an arsenic biomarker.

Hypertension, antihypertensive medications use and risk of age-related macular degeneration in California Teachers Cohort

Sustained and inadequately controlled hypertension can promote the development of age-related macular degeneration (AMD) through multiple biologic pathways. Epidemiologic studies of high blood pressure, antihypertensive therapies, and the risk of AMD thus far have been inconclusive. However, few studies evaluated risks according to the use of different classes of antihypertensive drugs or took combinations of use into account. We performed a prospective cohort study by linking the California Teachers Study (CTS) cohort (N = 88 481) to statewide hospital discharge records up to December 31, 2012. History of high blood pressure, regular use of antihypertensive medications, and comprehensive risk factor information was collected via self-administered questionnaires at baseline in 1995-1996, and information on specific classes of antihypertensive drugs was provided by a subsample of CTS participants who completed a follow-up questionnaire in 2000. We identified 1762 female teachers with AMD during 14.8 years of follow-up on average. Applying Cox proportional hazard regression, we estimated increased risks of AMD among women treated for hypertension at baseline (HR = 1.15, 95% CI: 1.03, 1.30); the magnitude of the association increased with longer duration of antihypertensive treatment. In the subsample with more specific information on type of medication use, we estimated a 45% increased risk of AMD among women receiving diuretics as monotherapy compared to women with medications more potent than diuretics (HR = 1.45, 95% CI 1.10, 1.90). In women treated with a combination of antihypertensive drugs, we observed no increased risk of AMD for any individual class of drugs.

Family history of premature myocardial infarction modifies the associations between bilateral oophorectomy and cardiovascular disease mortality in a US national cohort of postmenopausal women

OBJECTIVE

To test the hypothesis that a family history of premature myocardial infarction (FHPMI) will modify the associations between bilateral salpingo-oophorectomy (BSO) and mortality due to heart disease (HD), cardiovascular disease (CVD), or all-cause mortality with stronger associations observed for BSO occurring before 45 years.

METHODS

We analyzed data from 2,763 postmenopausal women aged 40 years or older who participated in the National Health and Nutrition Examination Survey (1988-1994) and were followed through December 31, 2015. Cox regression was used to estimate adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for mortality outcomes (HD, CVD, and all-cause).

RESULTS

At baseline, the average age was 62 years. There were 610 women with BSO, 338 women with FHPMI, and 95 women with both BSO and FHPMI. During a median follow-up of 22 years, 1,713 deaths occurred of which 395 and 542 were attributed to HD and CVD, respectively. In models adjusting for CVD risk factors and hormone therapy use, HD mortality was greater among women with both BSO and FHPMI compared to those without either of these conditions (HR: 2.88, 95% CI: 1.72-4.82, PInteraction = 0.016). HD mortality was higher among women with FHPMI and BSO at an earlier age (<45 y: HR: 4.32, 95% CI: 1.95-9.50 vs ≥45 y: HR: 1.60, 95% CI: 0.63-4.09). Similar observations were seen for CVD and all-cause mortality.

CONCLUSIONS

In this study, the risk of HD, CVD, and all-cause mortality in women with BSO was modified by an FHPMI with the risk limited to women undergoing BSO at younger ages.

Hysterectomy status and all-cause mortality in a 21-year Australian population-based cohort study

BACKGROUND

Hysterectomy is a common surgical procedure, predominantly performed when women are between 30 and 50 years old. One in 3 women in Australia has had a hysterectomy by the time they are 60 years old, and 30% have both ovaries removed at the time of surgery. Given this high prevalence, it is important to understand the long-term effects of hysterectomy. In particular, women who have a hysterectomy/oophorectomy at younger ages are likely to be premenopausal or perimenopausal and may experience greater changes in hormone levels and a shortened reproductive lifespan than women who have a hysterectomy when they are older and postmenopausal. Use of menopausal hormone therapy after surgery may compensate for these hormonal changes. To inform clinical decisions about postsurgery management of women who have a hysterectomy prior to menopause (ie, average age at menopause 50 years), it is useful to compare women with a hysterectomy to women with no hysterectomy and to stratify the hysterectomy status by whether or not women have had a bilateral oophorectomy, or used menopausal hormone therapy.

OBJECTIVE

We sought to investigate whether women who had a hysterectomy with ovarian conservation or a hysterectomy and bilateral oophorectomy before the age of 50 years were at a higher risk of premature all-cause mortality compared to women who did not have this surgery before the age of 50 years. We also sought to explore whether use of menopausal hormone therapy modified these associations.

STUDY DESIGN

Women from the midcohort (born 1946 through 1951) of the Australian Longitudinal Study on Women's Health were included in our study sample (n = 13,541). Women who reported a hysterectomy (with and without both ovaries removed) before the age of 50 years were considered exposure at risk and compared with women who did not report these surgeries before age 50 years. To explore effect modification by use of menopausal hormone therapy we further stratified hysterectomy status by menopausal hormone therapy use. Risk of all-cause mortality was assessed using inverse-probability weighted Cox regression models.

RESULTS

During a median follow-up of 21.5 years, there were 901 (6.7%) deaths in our study sample. Overall, there was no difference in all-cause mortality between women who reported a hysterectomy with ovarian conservation (hazard ratio, 0.86; 95% confidence interval, 0.72-1.02) or women who reported a hysterectomy and bilateral oophorectomy (hazard ratio, 1.02; 95% confidence interval, 0.78-1.34) and women with no hysterectomy. When stratified by menopausal hormone therapy use, women with hysterectomy and ovarian conservation before the age of 50 years were not at higher risk of all-cause mortality compared to no hysterectomy, regardless of menopausal hormone therapy use status. In contrast, among nonusers of menopausal hormone therapy only, women who reported a hysterectomy-bilateral oophorectomy before the age of 50 years were at a higher risk of death compared to women with no hysterectomy (hazard ratio, 1.81; 95% confidence interval, 1.01-3.25).

CONCLUSION

Hysterectomy with ovarian conservation before the age of 50 years did not increase risk of all-cause mortality. Among nonmenopausal hormone therapy users only, hysterectomy and bilateral oophorectomy before the age of 50 years was associated with a higher risk of death.

Potential Mechanisms of Age Acceleration Caused by Estrogen Deprivation: Do Endocrine Therapies Carry the Same Risks?

Longer duration of endocrine therapy decreases breast cancer recurrence and mortality, but these benefits need to be weighed against potential risks to overall health. Notable side effects of endocrine therapy include cataracts, uterine cancer, thromboembolic events, osteoporosis and fracture risk, chronic musculoskeletal complaints, as well as vaginal dryness and discharge, and vasomotor symptoms. Estrogen deprivation in healthy women younger than 50 years undergoing bilateral oophorectomy has been shown to accelerate the development of diseases related to aging, including coronary artery disease, cardiac arrhythmias, stroke, dementia, and osteoporosis, raising concern that even less dramatic modulation of estrogen homeostasis may adversely affect health outcomes. Diminished available estrogen at the cellular and molecular level may facilitate mechanisms that underlie the aging process, often termed the hallmarks of aging. In this review, we describe estrogen's role in normal physiology across tissues, review the effects of estrogen deprivation on health outcomes in the setting of both surgical and natural menopause, and examine the hallmarks of aging with attention to the effects of estrogen and estrogen blockade on each molecular mechanism underlying the aging process.

Cohort profile: the Mayo Clinic Cohort Study of Oophorectomy and Aging-2 (MOA-2) in Olmsted County, Minnesota (USA)

PURPOSE

This cohort study was established to investigate the effects of unilateral and bilateral oophorectomy on the ageing processes in women.

PARTICIPANTS

We used the records-linkage system of the Rochester Epidemiology Project (REP, http://www.rochesterproject.org) to identify 570 women who underwent unilateral oophorectomy and 1653 women who underwent bilateral oophorectomy in Olmsted County, Minnesota from 1988 through 2007 (20 years). Each woman was matched by age (±1 year) to a population-based referent woman who had not undergone any oophorectomy (570 referent women) or bilateral oophorectomy (1653 referent women). These four cohorts are being followed to assess morbidity and mortality and to study imaging and biological markers related to ageing.

FINDINGS TO DATE

An extensive medical record abstraction using the REP has been completed for each woman to obtain demographic, reproductive and adult life characteristics and extensive clinical information about the surgical procedure and subsequent oestrogen replacement therapy (or other sex steroid therapy). The cohorts have been used to date to study the accumulation of multiple chronic conditions following bilateral oophorectomy in women with or without chronic conditions at the time of the oophorectomy (or index date). From the cohorts, we have also derived a sample of 128 pairs of women for a case-control study linking adverse childhood or adult experiences to the risk of bilateral oophorectomy.

FUTURE PLANS

We hypothesise that the abrupt hormonal changes caused by bilateral oophorectomy in younger women have a major effect on the ageing processes across the full body. Therefore, we plan to investigate the risk of a wide range of chronic conditions following bilateral oophorectomy. Specific studies are underway for kidney diseases, psychiatric diseases and neurological diseases. In addition, we plan to invite a subsample of women from the bilateral oophorectomy cohort to participate in an in-person study involving brain imaging and the collection of biomarkers.

Is Surgical Menopause Associated With Future Levels of Cardiovascular Risk Factor Independent of Antecedent Levels? The CARDIA Study

In the present study, we compared changes in risk factors for cardiovascular disease (CVD) before and after natural menopause (NM), hysterectomy with at least 1 ovary conserved (HOC), or hysterectomy with bilateral oophorectomy (HBSO). Data were obtained from women 18-30 years of age who were enrolled in the Coronary Artery Risk Development in Young Adults Study (1985-2011). Piecewise linear mixed models were used to examine changes in CVD risk factors from baseline to the index visit (the first visit after the date of NM or hysterectomy) and after index visit until the end of follow-up. During 25 years of follow-up, 1,045 women reached menopause (for NM, n = 588; for HOC, n = 304; and for HBSO, n = 153). At baseline, women with either type of hysterectomy had less favorable values for CVD risk factors. When comparing the annual rates of change of all CVD risk factors from baseline until the index visit to those from the index visit to the end of follow-up, we saw a small increase in rate of change for high-density lipoprotein cholesterol (β = 0.28 mg/dL; P = 0.002) and a decrease for triglycerides (β =-0.006 mg/dL; P = 0.027) for all groups. Hysterectomy was not associated with risk factors for CVD after accounting for baseline values. However, antecedent young-adult levels of CVD risk factors were strong predictors of levels of postmenopausal risk factors.

Androgens, Bilateral Oophorectomy, and Cardiovascular Disease Mortality in Postmenopausal Women With and Without Diabetes: The Study of Osteoporotic Fractures

OBJECTIVE

Diabetes elevates cardiovascular disease (CVD) risk more markedly in women than in men. Because the high risk of CVD among women with type 2 diabetes (DM2) may be partly due to increased ovarian androgen production, we investigated whether a history of bilateral salpingo oophorectomy (BSO) is inversely associated with CVD mortality among women with DM2.

RESEARCH DESIGN AND METHODS

Data were obtained from 7,977 women (a random subset of 564 had measurements of sex-steroid hormones) enrolled in the Study of Osteoporotic Fractures (SOF), a community-based, multicenter study that monitored women aged ≥65 years for a mean of 15.1 years. Adjusted hazard ratios (HRs) and 95% CIs were calculated using Cox proportional hazards regression.

RESULTS

The average age at baseline was 71.5 years, with 6.3% and 18% of participants reporting a history of diabetes or BSO, respectively. In the subset of the SOF cohort with sex-steroid hormone measurements, those with DM2 had 43.6% significantly higher levels of free testosterone that were partly explained by age and adiposity, whereas total and free testosterone levels were lower in women with BSO than in those with intact ovaries. CVD mortality was elevated in women with DM2 without BSO (HR 1.95, 95% CI 1.62-2.35) as well as in women with DM2 and BSO (HR 2.56, 95% CI 1.79-3.65; P = 0.190 for interaction). Overall, BSO was not associated with CVD mortality (HR 1.05, 95% CI 0.89-1.23).

CONCLUSIONS

The association of diabetes with CVD was not reduced by BSO, suggesting that ovarian hyperandrogenemia may not be a primary mechanism to explain the high risk for CVD among women with DM2.

Cardiovascular disease among women with and without diabetes mellitus and bilateral oophorectomy

AIMS

Women with type-2 diabetes (DM2) are at high risk of cardiovascular disease (CVD) which may be partly due to increased ovarian androgen production. Since the association of bilateral oophorectomy (BSO) with CVD remains controversial, we evaluated whether BSO is inversely associated with CVD among DM2.

METHODS

Data were obtained from a national sample of 9599 postmenopausal women. Adjusted estimates and 95% confidence intervals (CIs) were calculated using logistic and Cox regression.

RESULTS

At baseline 2426 women had type-2 diabetes, of whom 580 had BSO. DM2 had adverse CVD risk profiles compared to women without diabetes, as did women with BSO with or without diabetes compared to those with intact ovaries. In DM2, BSO was positively associated with prevalent CVD (odds ratio: 1.63, 95%CI: 1.16-2.30). However, the higher odds were limited to women who had BSO before age 45 years (OR: 2.11, CI: 1.45-3.08). During a mean follow-up of 12.7 years, BSO in DM2 was positively associated with CVD mortality (hazard ratio: 2.23, CI: 1.25-3.99). Among women with BSO, those with family members who had MI before age 50 had elevated odds of CVD (OR: 2.29, CI: 1.56-3.37) compared to those without such family history (OR: 0.90, CI: 0.67-1.20), Pinteraction=0.04.

CONCLUSIONS

The risk of CVD is increased not decreased with BSO in DM2. Further, we propose that the association of BSO and CVD in young women with diabetes may partly reflect genetic susceptibility to CVD rather than an effect of ovarian hormones.

Long-term overall and disease-specific mortality associated with benign gynecologic surgery performed at different ages

OBJECTIVE

As bilateral salpingo-oophorectomy is frequently performed with hysterectomy for nonmalignant conditions, defining health outcomes associated with benign bilateral salpingo-oophorectomy performed at different ages is critical.

METHODS

We assessed mortality risk associated with benign total abdominal hysterectomy or bilateral salpingo-oophorectomy among 52,846 Breast Cancer Detection Demonstration Project follow-up study participants. Surgery and risk factor data were ascertained via baseline interview (1979-1986) and three questionnaires (1987-1998). During follow-up through December 2005 (mean, 22.1 y), 13,734 deaths were identified. We estimated hazard ratios (HRs) and 95% CIs for overall and disease-specific mortality for total abdominal hysterectomy or bilateral salpingo-oophorectomy performed by age 35, 40, 45, 50, or 55 years, compared with not having surgery, using landmark analyses and multivariable Cox regression.

RESULTS

Undergoing bilateral salpingo-oophorectomy by age 35 years was associated with increased mortality risk (HR35 y, 1.20; 95% CI, 1.08-1.34), which decreased with age (HR40 y, 1.12; 95% CI, 1.04-1.21; HR45 y, 1.10; 95% CI, 1.03-1.17). Total abdominal hysterectomy alone performed by age 40 years was associated with increased mortality risk to a lesser extent (HR40 y, 1.08; 95% CI, 1.01-1.15). Analyses based on matched propensity scores related to having gynecologic surgery yielded similar results. Elevated mortality risks were largely attributable to noncancer causes.

CONCLUSIONS

Benign gynecologic surgeries among young women are associated with increased mortality risk, which attenuates with age.

Pre-diagnosis oophorectomy, estrogen therapy and mortality in a cohort of women diagnosed with breast cancer

Introduction

Pre-diagnosis oophorectomy and estrogen therapy could impact mortality due to breast cancer and cardiovascular disease (CVD) among breast cancer survivors. Elective bilateral oophorectomy at the time of hysterectomy for benign conditions is not uncommon among US women.

Methods

We examined the association between pre-diagnosis total abdominal hysterectomy with bilateral salpingo-oophorectomy (TAHBSO) and both overall and cause-specific mortality in the Collaborative Breast Cancer Studies cohort. Medical history and prior estrogen use were collected during standardized telephone interviews. Vital status, including date and cause of death, was obtained by linkage with the National Death Index. Multivariate hazard ratios (HR) and 95% confidence intervals (CI) for cause-specific mortality were calculated using Cox proportional hazards regression.

Results

Seventeen percent (N = 1,778) of breast cancer survivors (mean age at diagnosis = 63.5) reported pre-diagnosis TAHBSO. During follow-up (mean = 9.5 years), 2,856 deaths occurred, including 1,060 breast cancer deaths and 459 CVD deaths. Breast cancer deaths occurred a median of 5.1 years after diagnosis; CVD deaths occurred further from diagnosis (median = 9.7 years). Women who reported pre-diagnosis TAHBSO had a 16% decrease in all-cause mortality (HR = 0.84; 95% CI: 0.76, 0.92) compared to those with an intact uterus and ovaries. This overall decrease reflected a 27% lower breast cancer mortality among women who never used postmenopausal hormones (HR = 0.73; CI: 0.55, 0.96) and 43% lower CVD risk among women who reported using estrogen (HR = 0.57; CI: 0.39, 0.83) after TAHBSO.

Conclusions

Information on prior TAHBSO and estrogen use can inform risk of death from both breast cancer and cardiovascular disease among breast cancer survivors.

Premature menopause and risk of neurological disease: basic mechanisms and clinical implications

Since basic scientific studies in the 1990s revealed dramatic gender differences in neurological damage from cerebral ischemia, significant evidence has accumulated for a neuroprotective role of ovarian-derived 17β-Estradiol (E2). Intriguingly, observational studies have further suggested that early and prolonged loss of ovarian E2 (premature menopause) leads to a doubled lifetime risk for dementia and a fivefold increased risk of mortality from neurological disorders, but some controversy remains. Here, we briefly summarize and analyze clinical cohort studies assessing the detrimental neurological outcomes of premature menopause. Furthermore, we discuss current basic science studies elucidating the molecular mechanisms underlying the enhanced risk of neurological disease in prematurely menopausal women and the "window of opportunity" for estrogen benefit. Finally, we highlight four critical issues in the field that require collaboration between basic scientists and clinicians for successful resolution, with the ultimate goal of maintaining optimal neurological health in prematurely menopausal women.

Bilateral oophorectomy and risk of cancer in African American women

PURPOSE

African American women are more likely to undergo hysterectomy, with or without bilateral oophorectomy, at younger ages than white women. It is well established that women who have a bilateral oophorectomy at younger ages are at reduced risk of breast cancer, and there is some evidence of an increased risk of colorectal and lung cancer.

METHODS

Using data from 44,514 women in the Black Women's Health Study, we prospectively investigated the relation of hysterectomy and oophorectomy to incidence of breast, colorectal, and lung cancer and to mortality from cancer. Hazard ratios (HRs) and 95 % confidence intervals (CIs) were estimated using Cox proportional hazards regression with control for confounding factors.

RESULTS

During 16 years of follow-up, hysterectomy alone, relative to no hysterectomy, was not associated with risk of breast, lung, or colorectal cancer. Bilateral oophorectomy, relative to hysterectomy with ovarian conservation, was inversely associated with risk of estrogen receptor-positive (ER+) breast cancer (HR 0.62; 95 % CI 0.45-0.85) but not with ER-negative breast cancer; age at surgery and menopausal hormone use did not modify the associations. HRs for the association of bilateral oophorectomy with incidence of colorectal and lung cancer were nonsignificantly increased for women who had surgery before age 40 years and had used menopausal hormones for less than 2 years (HR 1.65; 95 % CI 0.73-3.73 for colorectal cancer and HR 1.71; 95 % CI 0.68-4.31 for lung cancer). Bilateral oophorectomy was not associated with cancer mortality.

CONCLUSIONS

Bilateral oophorectomy was associated with reduced risk of ER+ breast cancer regardless of age at surgery and use of menopausal hormones. There were nonsignificant increases in risk of colorectal and lung cancer for women with oophorectomy at younger ages and short duration of menopausal hormone use.

The mortality toll of estrogen avoidance: an analysis of excess deaths among hysterectomized women aged 50 to 59 years

OBJECTIVES

We examined the effect of estrogen avoidance on mortality rates among hysterectomized women aged 50 to 59 years.

METHODS

We derived a formula to relate the excess mortality among hysterectomized women aged 50 to 59 years assigned to placebo in the Women's Health Initiative randomized controlled trial to the entire population of comparable women in the United States, incorporating the decline in estrogen use observed between 2002 and 2011.

RESULTS

Over a 10-year span, starting in 2002, a minimum of 18 601 and as many as 91 610 postmenopausal women died prematurely because of the avoidance of estrogen therapy (ET).

CONCLUSIONS

ET in younger postmenopausal women is associated with a decisive reduction in all-cause mortality, but estrogen use in this population is low and continuing to fall. Our data indicate an associated annual mortality toll in the thousands of women aged 50 to 59 years. Informed discussion between these women and their health care providers about the effects of ET is a matter of considerable urgency.

Long-term mortality associated with oophorectomy compared with ovarian conservation in the nurses' health study

OBJECTIVE

To report long-term mortality after oophorectomy or ovarian conservation at the time of hysterectomy in subgroups of women based on age at the time of surgery, use of estrogen therapy, presence of risk factors for coronary heart disease, and length of follow-up.

METHODS

This was a prospective cohort study of 30,117 Nurses' Health Study participants undergoing hysterectomy for benign disease. Multivariable adjusted hazard ratios for death from coronary heart disease, stroke, breast cancer, epithelial ovarian cancer, lung cancer, colorectal cancer, total cancer, and all causes were determined comparing bilateral oophorectomy (n=16,914) with ovarian conservation (n=13,203).

RESULTS

Over 28 years of follow-up, 16.8% of women with hysterectomy and bilateral oophorectomy died from all causes compared with 13.3% of women who had ovarian conservation (hazard ratio 1.13, 95% confidence interval 1.06-1.21). Oophorectomy was associated with a lower risk of death from ovarian cancer (four women with oophorectomy compared with 44 women with ovarian conservation) and, before age 47.5 years, a lower risk of death from breast cancer. However, at no age was oophorectomy associated with a lower risk of other cause-specific or all-cause mortality. For women younger than 50 years at the time of hysterectomy, bilateral oophorectomy was associated with significantly increased mortality in women who had never used estrogen therapy but not in past and current users: assuming a 35-year lifespan after oophorectomy: number needed to harm for all-cause death=8, coronary heart disease death=33, and lung cancer death=50.

CONCLUSIONS

Bilateral oophorectomy is associated with increased mortality in women aged younger than 50 years who never used estrogen therapy and at no age is oophorectomy associated with increased survival.

LEVEL OF EVIDENCE

I.