IMS: HRT in the early menopause

This document is adapted from the IMS Statement about HRT in the early menopause. For the full statement, including references and levels of evidence please see the IMS website: http://www.imsociety.org

International Menopause Society:  HRT in the early menopause

Introduction

Hormone replacement therapy (HRT) remains the first-line and most effective treatment for menopausal symptoms.

Quality of Life and Menopause

• In symptomatic postmenopausal women, quality of life and sexuality are improved by HRT.
• There is no evidence that so-called ‘natural' products and unregulated hormone products (compounded bio-identical) significantly improve quality of life.

HRT, coronary heart disease, stroke and thromboembolism

• HRT does not increase CHD risk in healthy women aged 50-59 years and may even decrease the risk.
• Oestrogen-alone therapy in the age group 50-59 was associated with significantly less coronary calcification (equivalent to a smaller plaque burden), which is consistent with findings of a lower coronary intervention score in women of this age in the WHI study.
• Early harm (more coronary events during the first 2 years of HRT) was not observed in the early postmenopause. The number of CHD events decreased with duration of HRT in both WHI clinical trials.
• Data derived from randomized controlled trials in women aged 50-59 are similar to the older observational data suggesting a protective effect of HRT on coronary disease.
• It is unclear at present whether there is a statistical significant  increase in stroke with standard HRT in healthy women aged 50-59. The WHI data showed no statistically significant increase in risk; nevertheless, even if statistically increased, as found in the Nurses' Health Study, the low prevalence of this occurrence in this age group makes the attributable risk extremely small.
• The risk of venous thrombosis is approximately two-fold higher with standard doses of oral HRT, but is a rare event in that the background prevalence is extremely low in a healthy woman under 60 years of age.
• The risk of venous thrombosis is possibly less with transdermal, compared with oral oestrogen therapy.

Breast

• There are multiple risk factors for breast cancer, including life-style factors especially alcohol intake, obesity and lack of exercise. These need to be included during counseling to put the magnitude of risk of HRT into an appropriate perspective.
• After 5 years' use of combined oestrogen and progestogen, there is a small increase in risk of breast cancer in North American women of about eight extra cases per 10,000 women per year. However, no significant increase was seen in women without prior use of HRT in the WHI study.
• Oestrogen-only use does not cause an increase in breast cancer for up to 7 years. In observational studies, a small increase in the risk with oestrogen-only therapy appears with long-term use.
• Women using combined HRT before a diagnosis of breast cancer have a reduced mortality.
• Combined oestrogen and progestogen therapy may cause increased breast density in up to 50% of postmenopausal women, dependent on the regimen (dosage, type of progestogen). The effect of oestrogen alone is smaller.
• Increased baseline breast density is a risk factor for breast cancer. There are no data to support a direct association between HRT-induced breast density changes and the risk of developing breast cancer.
• Many women who develop breast cancer have no known risk factors other than aging and most women with known risk factors do not develop breast cancer.
• Individual risk analysis for breast cancer is strongly recommended in clinical practice.

Bone

• Overall, HRT is effective in the prevention of all osteoporosis-related fractures, even in patients at low risk of fracture.
• It is therefore suggested that, in 50-59-year-old postmenopausal women, HRT is a cost-effective first-line treatment in the prevention of osteoporotic fractures.
• Low-dose preparations maintain a positive influence on bone indices such as bone mineral density.
• HRT has a positive effect on osteoarthritis and the integrity of intervertebral disks.

Cognition

• At present, there is no evidence of substantial cognitive decline across the menopausal transition. However, many women experience cognitive difficulties in association with vasomotor symptoms, sleep disturbances and mood changes.
• Clinical trial findings currently find no cognitive benefit among women initiating HRT late in the postmenopausal period (i.e. after age 65).
• Cognitive benefits from oestrogen replacement therapy appear to depend on age of initiation.
• Observational studies show a decreased risk of Alzheimer's disease in hormone users and typically involve women who initiated oestrogen therapy early in the menopausal transition.
• Limited data exists on the effect of progestogen added to oestrogen in the early postmenopause period. Clinical trial data suggest no cognitive benefit with MPA early in the menopause.

This edited version of the IMS statement has been provided by the Australasian Menopause Society. For more information about menopause and HRT see the AMS website http://www.menopause.org.au/  

Content updated 16 March 2009