Reproductive history, hormone replacement, and incidence of venous thromboembolism: the Longitudinal Investigation of Thromboembolism Etiology

Eligibility criteria for Menopausal Hormone Therapy (MHT): a position statement from a consortium of scientific societies for the use of MHT in women with medical conditions. MHT Eligibility Criteria Group

This project aims to develop eligibility criteria for menopausal hormone therapy (MHT). The tool should be similar to those already established for contraception A consortium of scientific societies coordinated by the Spanish Menopause Society met to formulate recommendations for the use of MHT by women with medical conditions based on the best available evidence. The project was developed in two phases. As a first step, we conducted 14 systematic reviews and 32 metanalyses on the safety of MHT (in nine areas: age, time of menopause onset, treatment duration, women with thrombotic risk, women with a personal history of cardiovascular disease, women with metabolic syndrome, women with gastrointestinal diseases, survivors of breast cancer or of other cancers, and women who smoke) and on the most relevant pharmacological interactions with MHT. These systematic reviews and metanalyses helped inform a structured process in which a panel of experts defined the eligibility criteria according to a specific framework, which facilitated the discussion and development process. To unify the proposal, the following eligibility criteria have been defined in accordance with the WHO international nomenclature for the different alternatives for MHT (category 1, no restriction on the use of MHT; category 2, the benefits outweigh the risks; category 3, the risks generally outweigh the benefits; category 4, MHT should not be used). Quality was classified as high, moderate, low or very low, based on several factors (including risk of bias, inaccuracy, inconsistency, lack of directionality and publication bias). When no direct evidence was identified, but plausibility, clinical experience or indirect evidence were available, "Expert opinion" was categorized. For the first time, a set of eligibility criteria, based on clinical evidence and developed according to the most rigorous methodological tools, has been defined. This will provide health professionals with a powerful decision-making tool that can be used to manage menopausal symptoms.

Cardiovascular Risk/Benefit Profile of MHT

Background and Objectives: Data emerging from the Women’s Health Initiative (WHI) study point toward an association between menopausal hormone therapy (MHT) and cardiovascular (CV) risk. However, post hoc subgroup analyses stratifying participants according to their age and time since menopause, have opened the way to a better understanding of the relationship between estrogen and CV risk. The aim of this review was to revise the current literature and evaluate the CV risk or benefit following administration of MHT considering several factors such as MHT timing, dose, route of administration, and formulation. Materials and Methods: An electronic databases search of MEDLINE (PubMed), Cochrane Central Register of Controlled Trials, Web of Science, SCOPUS, congress abstracts, and Grey literature (Google Scholar; British Library) was performed, with the date range from each database’s inception until June 2019. All the studies evaluating MHT and cardiovascular risk, including thromboembolism or stroke, were selected. Results: Timing of MHT initiation was shown to be a critical factor in CV risk assessment. In concordance with the “timing hypothesis”, healthy symptomatic women who initiated MHT when aged younger than 60 years, or who were within 10 years of menopause onset, have demonstrated a reduction in both coronary heart disease (CHD) risk and all-cause mortality. In particular, MHT therapy was associated with improvement of subclinical signs of atherosclerosis. Venous thromboembolism (VTE) risk is reduced when low doses of oral estrogen are used. Moreover, transdermal hormonal application significantly reduces CV risk compared with oral administration. MHT impact on the CV system is influenced by either factors inherent to the specific regimen, or factors inherent to the specific patient. Hence, individualization of care is necessary. Conclusion: CV risk calculation should be considered by clinicians in order to exclude patients with high CV risk, in whom MHT is contraindicated. Assessing risks and benefits in a patient-centered approach according to individual’s features, health status, and personal preferences is important in order to realize a safe and effective treatment.

Use of hormone replacement therapy and risk of venous thromboembolism: nested case-control studies using the QResearch and CPRD databases

OBJECTIVE

To assess the association between risk of venous thromboembolism and use of different types of hormone replacement therapy.

DESIGN

Two nested case-control studies.

SETTING

UK general practices contributing to the QResearch or Clinical Practice Research Datalink (CPRD) databases, and linked to hospital, mortality, and social deprivation data.

PARTICIPANTS

80 396 women aged 40-79 with a primary diagnosis of venous thromboembolism between 1998 and 2017, matched by age, general practice, and index date to 391 494 female controls.

MAIN OUTCOME MEASURES

Venous thromboembolism recorded on general practice, mortality, or hospital records. Odds ratios were adjusted for demographics, smoking status, alcohol consumption, comorbidities, recent medical events, and other prescribed drugs.

RESULTS

Overall, 5795 (7.2%) women who had venous thromboembolism and 21 670 (5.5%) controls had been exposed to hormone replacement therapy within 90 days before the index date. Of these two groups, 4915 (85%)and 16 938 (78%) women used oral therapy, respectively, which was associated with a significantly increased risk of venous thromboembolism compared with no exposure (adjusted odds ratio 1.58, 95% confidence interval 1.52 to 1.64), for both oestrogen only preparations (1.40, 1.32 to 1.48) and combined preparations (1.73, 1.65 to 1.81). Estradiol had a lower risk than conjugated equine oestrogen for oestrogen only preparations (0.85, 0.76 to 0.95) and combined preparations (0.83, 0.76 to 0.91). Compared with no exposure, conjugated equine oestrogen with medroxyprogesterone acetate had the highest risk (2.10, 1.92 to 2.31), and estradiol with dydrogesterone had the lowest risk (1.18, 0.98 to 1.42). Transdermal preparations were not associated with risk of venous thromboembolism, which was consistent for different regimens (overall adjusted odds ratio 0.93, 95% confidence interval 0.87 to 1.01).

CONCLUSIONS

In the present study, transdermal treatment was the safest type of hormone replacement therapy when risk of venous thromboembolism was assessed. Transdermal treatment appears to be underused, with the overwhelming preference still for oral preparations.

How do you decide on hormone replacement therapy in women with risk of venous thromboembolism?

Women are increasingly encouraged to participate in making decisions about hormone replacement therapy (HRT). In postmenopausal women with severe vasomotor symptoms, HRT can significantly improve the quality of life. However, the use of HRT may also increase the risk of venous thromboembolism (VTE), the risk which depends of both treatment-related and patient-related factors. This review summarizes some important points about the selection of the safest hormonal replacement modality in women with a history of VTE and management of VTE risks in postmenopausal women wishing to take HRT.

Hormone therapy and risk of venous thromboembolism among postmenopausal women

Despite a decrease in the use of postmenopausal hormone therapy (HT) over the last decade, many women are still prescribed this treatment, as it remains the most effective means of counteracting climacteric symptoms. Its use declined when it was shown that HT increases the risk of breast cancer, stroke and venous thromboembolism (VTE). Nevertheless, that benefit/risk ratio was established among women using oral estrogens alone or combined with a specific progestogen and it cannot necessarily be extrapolated to other HTs. Oral estrogens increase the risk of VTE especially during the first year of treatment and past users revert to a similar risk as women who have never used them. There is now growing evidence that VTE risk among HT users strongly depends on the route of administration. Indeed, transdermal estrogens, unlike oral estrogens, are not associated with an increased VTE risk and biological data support this difference between oral and transdermal estrogens. In addition, transdermal estrogens may not confer additional risk in women at high risk of VTE. Significant differences in thrombotic risk between HT preparations also relate to the concomitant progestogen. Studies have consistently shown that VTE risk is higher among users of combined estrogens plus progestogens than among users of estrogens alone. With respect to the different pharmacological classes of progestogens, two observational studies found that norpregnane derivatives are associated with an increased VTE risk, whereas micronized progesterone may be safe with respect to thrombotic risk. In conclusion, transdermal estrogens alone or combined with micronized progesterone may represent the safest alternative for women who require HT.

Age at menopause, reproductive history, and venous thromboembolism risk among postmenopausal women: the Women's Health Initiative Hormone Therapy clinical trials

OBJECTIVE

This study aims to investigate venous thromboembolism (VTE) risk in relation to age at menopause, age at menarche, parity, bilateral oophorectomy, and time since menopause, as well as any interaction with randomized hormone therapy (HT) assignment, among postmenopausal women.

METHODS

Using pooled data from the Women's Health Initiative HT clinical trials including 27,035 postmenopausal women aged 50 to 79 years who had no history of VTE, we assessed the risk of VTE in relation to age at menopause, age at menarche, parity, bilateral oophorectomy, and time since menopause by Cox proportional hazards models. Linear trends, quadratic relationships, and interactions of reproductive life characteristics with HT on VTE risk were systematically tested.

RESULTS

During follow-up, 426 women reported a first VTE, including 294 non-procedure-related events. No apparent interaction of reproductive life characteristics with HT assignment on VTE risk was detected, and there was not a significant association between VTE and age at menarche, age at menopause, parity, oophorectomy, or time since menopause. However, analyses restricted to non-procedure-related VTE showed a U-shaped relationship between age at menopause and thrombotic risk that persisted after multivariable analysis (P < 0.01). Compared with women aged 40 to 49 years at menopause, those who had early menopause (age <40 y) or late menopause (age >55 y) had a significantly increased VTE risk (hazard ratio [95% CI]: 1.8 [1.2-2.7] and 1.5 [1.0-2.4], respectively).

CONCLUSIONS

Reproductive life characteristics have little association with VTE and do not seem to influence the effect of HT on thrombotic risk among postmenopausal women. Nevertheless, early and late onset of menopause might be newly identified risk factors for non-procedure-related VTE.

Menopausal hormone therapy and venous thromboembolism

Menopausal hormone therapy (MHT) is the most effective method of treating vasomotor symptoms and other climacteric symptoms related to estrogen deficiency in peri- and postmenopausal period. In addition to estrogen replacement, women with preserved uterus require the addition of progestagen in order to ensure endometrial safety. One of rare but severe complications of MHT is venous thromboembolism (VTE). The incidence of VTE rises in parallel to women's age and body weight. The condition is also linked to hereditary and acquired risk factors. Oral estrogens increase the risk of venous thromboembolic complications to varying extents, probably depending on their type and dose used. Observational studies have not found an association between an increased risk of VTE and transdermal estrogen treatment regardless of women's age and body mass index (BMI). Micronized progesterone and pregnanes, including dydrogesterone, have no effect on the risk of VTE, whereas norpregnane progestagens cause an additional increase in risk. Among hormonal preparations which are commercially available in Poland, the combination of transdermal estradiol with oral dydrogesterone appears to be the optimum choice, as it does not elevate the risk of VTE (compared to patients not using MHT), and dydrogesterone seems to be the progestagen of choice.

Hormone replacement therapy and venous thromboembolism

Hormone replacement therapy (HRT) for post-menopausal women is known to promote venous thromboembolism (VTE), i.e., deep venous thrombosis and pulmonary embolism, though the absolute risk for a given patient is very small. The risk of VTE appears to be greatest soon after the initiation of HRT and returns to the baseline level of risk of non-HRT users after discontinuation. There is inconsistent data about whether estrogen-only or combined estrogen-progestin HRT are associated with similar VTE risk. Retrospective analyses suggest that transdermal HRT is not as prothrombotic as oral HRT, though this has not been evaluated in randomized clinical trials. Increasing age and weight further promote HRT's VTE risk. Some studies have investigated whether prothrombotic combinations may increase HRT's VTE risk and there is evidence that Factor V Leiden may do this. However, no benefit to screening prospective HRT users has been described, yet. Advanced proteomic and genomic studies may hold promise in the future for better elucidating which HRT users are at highest risk for VTE. Presently, physicians and prospective HRT users should discuss the potential risks and benefits for the individual patient, acknowledging there is no way to fully mitigate the risk of VTE. This article is part of a Special Issue entitled 'Menopause'.

Venous thromboembolism risk in relation to use of different types of postmenopausal hormone therapy in a large prospective study

BACKGROUND

Current use of menopausal hormone therapy (HT) increases the risk of venous thromboembolism (VTE) and the formulations used may affect risk.

METHODS

A total of 1,058,259 postmenopausal UK women were followed by record linkage to routinely collected National Health Service hospital admission and death records. HT use and risk of VTE was examined using Cox regression to estimate relative risks (RRs) and 95% confidence intervals (CIs).

RESULTS

During 3.3 million years of follow-up, 2200 women had an incident VTE, diagnosed, on average, 1.5 years after last reporting HT use. RRs in current vs. never users at last reporting varied by HT formulation: the risk was significantly greater for oral estrogen-progestin than oral estrogen-only therapy (RR = 2.07 [95%CI, 1.86-2.31] vs. 1.42 [1.21-1.66]), with no increased risk with transdermal estrogen-only therapy (0.82 [0.64-1.06]). Among users of oral estrogen-progestin, the risk from HT varied by progestin type, with significantly greater risks for preparations containing medroxyprogesterone acetate than other progestins (2.67 [2.25-3.17] vs. 1.91 [1.69-2.17]; Pheterogeneity = 0.0007). Current users of oral HT at last reporting had twice the risk of VTE in the first 2 years after starting HT than later (Pheterogeneity = 0.0006). Associations were similar for deep vein thrombosis with and without pulmonary embolism. Over 5 years, 1 in 660 who had never used HT were admitted to hospital for (or died from) pulmonary embolism, compared with 1 in 475 current users of oral estrogen-only HT,1 in 390 users of estrogen-progestin HT containing norethisterone/norgestrel, and 1 in 250 users of estrogen-progestin HT containing medroxyprogesterone acetate.

CONCLUSIONS

The risk of VTE varied considerably by HT formulation, being greatest in users of oral estrogen-progestin HT, especially formulations containing medroxyprogesterone acetate.

Risk factors for venous thromboembolism in pre-and postmenopausal women

INTRODUCTION

Hemostasis in women is affected by changes of estrogen levels. The role of endogenous estrogens on risk of venous thromboembolism (VTE) remains unclear. The aim of this study was to investigate the importance of acquired and genetic risk factors for VTE in pre-and postmenopausal women.

METHOD

In a nationwide case-control study we included as cases 1470 women, 18 to 64years of age with a first time VTE. The 1590 controls were randomly selected and matched by age to the cases. Information on risk factors was obtained by interviews and DNA-analyses. We used unconditional logistic regression to calculate odds ratios (ORs) with 95% confidence intervals (CIs).

RESULTS

The ORs were generally of similar magnitude in pre- and postmenopausal women. The highest risk was for the combination of surgery and cast (adjusted OR 54.12, 95% CI 16.62-176.19) in postmenopausal women. The adjusted OR for use of menopausal hormone therapy was 3.73 (95% CI 1.86-7.50) in premenopausal and 2.22 (95% CI 1.54-3.19) in postmenopausal women. Overweight was linked to an increased risk and exercise to a decreased risk, regardless of menopausal status.

CONCLUSION

Menopausal status had only minor influence on the risk levels. Acquired transient risk factors conveyed the highest risks for VTE.

EMAS position statement: Managing menopausal women with a personal or family history of VTE

INTRODUCTION

Venous thromboembolism (VTE), including deep venous thrombosis (DVT) and pulmonary embolism (PE), is a serious cardiovascular event whose incidence rises with increasing age.

AIMS

To formulate a position statement on the management of the menopause in women with a personal or family history of VTE.

MATERIAL AND METHODS

Literature review and consensus of expert opinion.

RESULTS AND CONCLUSIONS

Randomized controlled trials have shown an increased risk of VTE in oral hormone therapy (HT) users. There are no randomized trial data on the effect of transdermal estrogen on VTE. Recent observational studies and meta-analyses suggest that transdermal estrogen does not increase VTE risk. These clinical observations are supported by experimental data showing that transdermal estrogen has a minimal effect on hepatic metabolism of hemostatic proteins as the portal circulation is bypassed. A personal or family history of VTE, especially in individuals with a prothrombotic mutation, is a strong contraindication to oral HT but transdermal estrogen can be considered after careful individual evaluation of the benefits and risks. Transdermal estrogen should be also the first choice in overweight/obese women requiring HT. Observational studies suggest that micronized progesterone and dydrogesterone might have a better risk profile than other progestins with regard to VTE risk. Although these findings should be confirmed by randomized clinical trials, they strongly suggest that both the route of estrogen administration and the type of progestin may be important determinants of the overall benefit-risk profile of HT.