HRT Risks and Benefits
By Dr.Heather Currie, MB BS, FRCOG, MRCGP, MFFP.
Hormone Replacement Therapy (HRT) has received much media attention over the last few years, some good, some bad. Both women and their doctors and nurses are often understandably confused firstly about whether or not to use HRT (does it work, is it safe), then about what type, and finally about how long it can be used.
So, does it work?
For control of menopausal symptoms due to estrogen deficiency such as hot flushes, night sweats, poor sleeping, joint aches, low mood, vaginal dryness, discomfort and irritation, without doubt, HRT is still the most effective treatment currently available. Benefits are often noticed within a few weeks of treatment and generally symptoms remain controlled while it is being taken. The control of menopausal symptoms continues to be the main indication for using HRT where improvement in quality of life has been demonstrated. Other benefits include a reduction in osteoporotic fractures, and reduction in diabetes and death.
Is it safe?
Some trials on the effects of HRT have been reported over the last few years and have received much attention. Although initial reports, particularly from the Women’s Health Initiative (WHI) trial suggested that women who used HRT had an increased risk of heart disease, stroke, blood clot and breast cancer, it has now become clear that these risks don’t apply to all women taking HRT; risk is influenced by age and time since menopause as well as type of HRT.
After much debate and re-analysis of trial results, it seems that now, for the majority of women who either have an early (before the age of 45) or premature (before the age of 40) menopause, or who are having menopausal symptoms, HRT is safe and can provide significant benefits with minimal risk. Generally, for women with an early or premature menopause, the benefits of HRT both for symptom control and long term health, far outweigh the risks, and they should consider taking HRT up to the average age of the menopause (51 to 52). For women who are having troublesome symptoms, the benefits of HRT for symptom control and improved quality of life, outweigh the risks right up to the age of 60. After 60, benefits and risks start to be equal, and after 70, there may be more risks than benefits from taking HRT. Having said that, there are some women in there 70’s and even 80’s who still choose to continue HRT, believing that it is still beneficial to them; it has to be an individual, informed choice.
So what are the risks?
Much controversy still surrounds the effect of HRT on the cardiovascular system but it seems that increased risk of heart disease applies if HRT is started some 13-14 years after the menopause, whereas recent evidence suggests that it is more likely to provide cardiovascular benefit if commenced near the menopause, during the "window of opportunity".
The main risk of HRT remains a doubling of the risk of venous thromboembolism but when HRT is used around the time of the menopause, the overall risk is small and so the actual numbers affected are still very small. Further, the risk is thought to be much less with non-tablet route of HRT such as patch or gel, compared to tablet form. The risk of venous thromboembolism increases with age, obesity, immobility, and underlying thrombophilia. If HRT is used in the presence of other risk factors, transdermal route would be recommended and consideration should be given to discussing with a haematologist or menopause specialist. Although many women fear that HRT will cause weight gain, weight gain in users of HRT is similar to non-users.
The risk of breast cancer with HRT continues to cause most concern among both women and their health care providers. Firstly it is now clear that different types of HRT are associated with different risk; the Women's Health Initiative trial showed a reduction of 8 cases of breast cancer per 10,000 women per year in estrogen only users (women who had had a hysterectomy) at 7 years. In women who had not had a hysterectomy and were taking combined HRT (estrogen plus progestogen) the increase in risk only became significant after 7 years when it was an additional 8 cases per 10,000 women per year thereafter. Any increase in risk is of concern, but this appears to be a very small risk which, for many women, will be outweighed by benefits.
What type?
The type of HRT used is determined by type of symptoms present, whether or not the patient has had a hysterectomy, and, if not, whether or not periods are still present.
Firstly regarding types of symptoms: if the main problems are the vaginal and bladder symptoms such as vaginal dryness, irritation, discomfort during sex, passing urine frequently and/or discomfort when passing urine, then all that may be needed is vaginal estrogen which can be taken in the form of a small vaginal tablet inserted with an applicator, vaginal pessary, vaginal cream or vaginal ring. Vaginal estrogen is concentrated in the vagina and bladder and does not produce significant systemic levels.
If however, the symptoms are “systemic” - flushes, sweats, joint aches, mood changes, or if HRT is being taken because of an early or premature menopause, then the hormones need to also be systemic. In this case, there are two main divisions: HRT following hysterectomy and HRT with the uterus intact.
In women who have had a hysterectomy, HRT can be taken in the form of estrogen only. There are several options from which women may choose. Some may start with a daily tablet, however there are certain situations, such as poor control of symptoms with tablets, bowel disorder which may affect absorption of tablets, some medical conditions, and individual preference, where estrogen can be given in a way which allows absorption through the skin. This can be a twice weekly or weekly patch, applied to the hips, buttocks, abdomen or thighs, or a daily gel applied to the arms and legs. Patches have improved in their design over the years and do now stay on well with minimal skin reaction, but for some women, skin irritation can be a problem. The daily gel rarely produces skin problems and for some women is cosmetically more acceptable than a patch. Finally, estrogen only can be taken via an implant, a small pellet which is inserted under the skin in the abdomen and replaced every six months.
Women who have not had a hysterectomy must take progestogen in addition to the estrogen to reduce the risk of endometrial hyperplasia and cancer. Progestogen can be combined with estrogen tablets or patches, or can be taken separately as a tablet, or as Mirena, the progestogen releasing intra-uterine system.
Recently micronized progesterone, in capsule form, has become available in the UK which may be suitable for those ladies experiencing problems with synthetic progestogens.
The way that progestogen in tablet, capsule or patch form is given is determined by whether or not the patient is still having some kind of period pattern—if so progestogen is given for part of the month which continues the monthly bleed in the majority of users (Sequential HRT). If periods have stopped, progestogen can be taken every day, avoiding the monthly bleed (continuous combined or period-free HRT).
How long can HRT be taken?
For women who have had an early or premature menopause, HRT should generally be taken up to the early 50’s—the average time of the natural menopause. For women taking HRT for control of menopausal symptoms, they should be able to take HRT for as long or as little as they feel the benefits outweigh the risks for them. The duration therefore varies between individuals and is determined by past history, family history and other medical problems, but mostly by the duration of troublesome symptoms; an unpredictable number of years. When settled on a certain type of treatment, annual review with a doctor or nurse should take place to discuss the ongoing risk/benefit analysis and at times, to have a trial off HRT to assess whether or not it is still required. Duration of treatment is a very individual choice, determined by individual circumstances; no woman should be told either that she HAS to take HRT, nor that she HAS to stop. Instead women should be helped to make an informed choice.
The important decision of whether or not to take HRT and if so what type, what dose and for how long, must be individualised. There is a move towards using safer types, safer routes and lower doses to minimise risks and side effects while maximising benefits.
Dr.Heather Currie, MB BS, FRCOG, MRCGP, MFFP.
Associate Specialist Gynaecologist and Obstetrician, Dumfries and Galloway Royal Infirmary, Dumfries.
In 1993, she set up the first Dumfries hospital-based menopause clinic. She continues to run menopause clinics and is a member of the British Menopause Society Council. She is also the founder and Managing Director of the Menopause Matters website and magazine.
The British Menopause Society www.thebms.org.uk
Menopause Matters www.menopausematters.co.uk