HRT risks need to balanced with benefits

Adapted from Editorial BMJ 19 October 19 by Janice Rymer et al.

In the UK most women go through the menopause aged between 45 and 55. About half of them will get symptoms such as flushes, sweats, low mood, anxiety, joint and muscle pain, vaginal dryness, reduced sex drive, and hip fractures in later life. Hormone replacement therapy can turn these symptoms around.

Women’s health specialists are concerned that a meta-analysis published in the Lancet does not evenly show the benefits of HRT compared to the risks and think that the NICE guidance in 2015 looked more comprehensively at all the available evidence. They don’t want either women or doctors to stop HRT unnecessarily.

The Lancet showed that in the UK one in 16 women who have never taken HRT will develop breast cancer between the ages of 50 and 69.  If a woman of normal body mass index (under 25) starts HRT in her 40s or 50s the additional risk of getting breast cancer is one in 200 for oestrogen only HRT, one in 70 for daily oestrogen and progestogen for part of the month, and one in 50 for preparations with a mix of oestrogen and progesterone daily.  But body weight and alcohol have a greater effect on getting breast cancer than HRT. For instance, being overweight or obese will increase the rate of breast cancer six times compared to combined HRT.

The Lancet study looked at how many cases of breast cancer started but did not look at the mortality rate. A recent systematic review did. This showed that if a woman started HRT close to the menopause there was an apparent reduction in all cause mortality and cardiac death with no evidence of an increase in deaths from breast cancer.

The womens’ health specialists are concerned that the bone benefits and cardiac benefits, especially for women going through an early menopause, will be ignored if undue weight is put on the small increase in breast cancer diagnosis, over the symptomatic benefits and improvement in total mortality.

BMJ 2019;367:15928