Hormone replacement therapy (HRT) is the taking of oestrogens and progesterones for the management of menopausal symptoms and conditions.
Menopause
The menopause is defined as twelve months after a woman’s last period. However, symptoms can occur before this. The period around the menopause where a woman may have symptoms is termed the ‘climacteric’.
Problems associated with the menopause include vasomotor symptoms (hot flushes, night sweets, & irritability), osteoporosis (brittle bones), urogenital atrophy (thinking of the vagina and bladder walls), and cardio-vascular disease (heart disease).
HRT
Many women take oestrogens (along with a class of drug called progesterone) to help with the above problems of the menopause. This can be taken as a pill, patch, implant, nasal spray, or vaginal ring.
Most people have to take both oestrogens and progesterone for HRT because taking oestrogens alone increases the risk of cancer of the womb. However, women who have had a hysterectomy for anything other than womb cancer need not take progesterones. In addition, a device called an intrauterine system can be placed in the womb. This provides progesterone to the womb locally without a large amount going into the blood stream.
Oestrogens
Taking oestrogen in the form of hormone replacement therapy (HRT) was initially thought to help with all the symptoms and problems associated with the menopause. However, it is now known that oestrogen help for some but not all of these problems. Furthermore, there are some side-effects which need to be understood.
Vaso-motor instability: Oestrogens have proven efficacy in dealing with vaso-motor instability. They are probably the most effective drug although other drugs exist that can help with these symptoms.
Osteoporosis: Oestrogens help to prevent osteoporosis. However, biphosphonates have comparable effects to oestrogens. There are also other methods of reducing the risk of osteoporosis.
Uro-genital atrophy: This is dryness and shrinking of the vagina and base of the bladder. Oestrogens have proven efficacy in dealing with Uro-genital atrophy. However, other local preparations are also effective.
Cardio-vascular disease: Large studies have demonstrated that oestrogens are not effective at preventing against heart disease.
Alzheimer’s disease: Oestrogens may help to prevent Alzheimer’s disease but the data is not conclusive and there may be no effect.
Worries
There are some worries with HRT. However, these have to be placed into context. The worries that many women have include womb cancer, breast cancer, thrombo-embolism, stroke, heart attacks, gall stones, liver problems and benign breast disease.
Womb cancer: In the early days of HRT there was an association with womb cancer. However, nowadays, a drug called progesterone is added to HRT if a woman has not had a hysterectomy. Therefore, there is no longer an association with womb cancer and HRT.
Breast cancer: The evidence suggests that there is a small increased risk of breast cancer. This risk increases from 45 in 1000 to 47 in a 1000 over five years and 52 in 1000 over 10 years. Another study demonstrated that the risk was highest with HRT that contained both oestrogens and progesterones. The risk of dying from a breast cancer is probably less with HRT related cancers. The overall increased risk of dying from breast cancer has been estimated to be 1 in 300.
Thrombo-embolism: Thrombo-embolism is the formation of blood clots. These normally occur in the legs (Deep Vein Thrombosis) but can also break off in the blood stream and lodge in the lung (Pulmonary Embolus). The popular press call this the economy class syndrome as it can occur while flying on an aeroplane. The risk of a fatal thrombo-embolism is increased on HRT by only by a very small amount.
Stroke: The risk of stroke is increased on HRT by a small amount.
Heart attacks: The risk of heart attacks may be increased slightly although this is not clear.
Gall stones: There may be a small increased risk of gall stones with HRT.
Liver problems: Liver problems can get worse with HRT in women who already have liver disease.
Benign breast disease: Symptoms from benign breast disease can be worse on HRT.
Alternatives for prevention of osteoporosis
Exercise: Osteoporosis is markedly reduced in women who exercise over 20 minutes a day.
Calcium and vitamin D: Both these supplements are recommended to reduce the risk of osteoporosis.
Biphosphonates: These are a class of drugs that are as effective as oestrogens in preventing and treating osteoporosis. The two most common are called Alendronate and risedronate. They have few side effects, the most common being inflammation of the oesophagus when taken incorrectly. More recently worries have occurred with breakdown of boney tissue in the jaw.
Raloxifene: This is a type of drug called a selective oestrogen receptor modulator which has some oestrogen-like effects on the bone. Another drug which may behave in a similar way is the breast cancer drug called Tamoxifen.
Other drugs: These include the nasal spray or injection calcitonin and the cholesterol lowering drugs called statins. They all have some effect either in humans or in animals.
Urogenital atrophy
This is often relieved with vaginal lubricants (such as KY jelly) and moisturisers (such as Replens). A number of vaginal oestrogen preparations are also available. Low dose preparations are recommended as they do not increase the concentrations of oestrogens in the blood stream by a large amount.
Vasomotor instability
A number of drugs are available that help with vasomotor instability. Soy compounds containing phytoestrogens are often promoted by food companies. However, several studies have shown little or no benefit with a theoretical increased risk of breast cancer.
Mesgestrol (Megace): Is a synthetic progestin usually used in the treatment of breast cancer. It gives some improvement in up to 85% of women but hot flushes are worse to begin with. The main side effect is weight gain and it cannot be stopped suddenly due to a possible adverse affect on the adrenal gland.
Clonidine: This is usually given as a patch and acts on the nerve receptors responsible for hot flushes. It’s effect is variable.
SSRI: This is a class of drug usually used as an antidepressant but is also effective for hot flushes. Examples include venlafaxine and fluoxetine.
Other drugs: Other drugs that have been shown to be of some benefit include one called Verlipride which acts on a substance called dopamine and Gabapentin which is an antiepileptic.
