Note: hormone therapy (HT) may also be referred to as hormone replacement therapy (HRT).

The Women’s Health Initiative (WHI) is an important study on menopause, which has had global effect on women’s use of HT among women who did not have incontinence at the beginning of the trial.

The risk appeared to be highest for women experiencing stress incontinence, followed by a group of women who had both stress and urge incontinence. But there appeared to be no increase in risk in developing urge incontinence alone in those women on oestrogen and progestin, however there was a small increase in risk on oestrogen only therapy.

Among women who experienced incontinence at the beginning of the trial there was an increase in risk.

What do the latest findings show in relation to incontinence?

Results show that in the oestrogen and progestin trial and the oestrogen only trial, the risk of urinary incontinence increased after one year¹.

What exactly did the trial find?

The WHI trial of approximately 16,000 women in the oestrogen and progestin arm and 10,000 women in the oestrogen only arm studied the effects of HT on the incidence and severity of incontinence symptoms.

• The trial showed that over 2/3 of the women were over 60 years of age.

• 64% taking Oestrogen and Progestin were 10 years post menopause.

• 82% taking Oestrogen alone were 10 years post menopause.

• 60% of those with frequency of leakage was between once a month to once a week.

• 70% found the leakage not at all or only a little bothersome.

• 80% - 90% found that the leakage never, or almost never, limited their activities.

The study showed that there was an increase in urinary incontinence in all groups, including those women not receiving any hormones, over the first year of the study. There was a higher risk for women with stress incontinence (that is leakage with coughing and sneezing) who were receiving hormone therapy. In the group using oestrogen alone the incidence of urinary incontinence at 3 years was the same in both groups.

About incontinence

Urinary incontinence is often associated with vaginal dryness and atrophic signs (thinning of the lining of the vagina and urinary frequency, and increased risk of urinary tract infections), for which the first treatment of choice would be vaginal oestrogens (topical therapy), not hormone treatment given by tablets, by a patch, gel or implants (systemic therapy). Studies have shown that 40% of women on systemic therapy have no effect on vaginal symptoms.

Incontinence naturally increases with age and with the number of years a woman is post-menopause. Other factors that influence the likelihood of developing stress incontinence include vaginal delivery of large babies, being overweight, chronic cough or heavy lifting. Needing to go to the toilet frequently will also be aggravated by not drinking enough, too many caffeine based drinks and a history of bladder infections.

Management of urinary incontinence involves making a diagnosis of the type of incontinence, modifying aggravating factors and specific measures for the type of incontinence. The use of systemic hormone therapy has never been indicated in the treatment of urinary incontinence, rather local use of oestrogen into the vagina has been used with improvement in symptoms for some time. This was not assessed in the above study.

Conclusion

Hormone therapy is not a treatment for urinary incontinence, but if incontinence is associated with other symptoms, such as vaginal dryness, then topical oestrogens may be appropriate. Each woman's experience is unique and each woman needs to weigh up the risks and benefits with her doctor in managing her symptoms.

Reference

1. Hendrix SL, Cochrane BB, Nygaard IE, Handa VL, Barnabei VM, Iglesia C, Aragaki A, Naughton MJ, Wallace RB, McNeeley SG. Effects of estrogen with and without progestin on urinary incontinence. JAMA. 2005 Feb 23;293(8):935-48.

Content updated June 10, 2005