The Midlife Bladder

In this morning’s BSM symposium we were also given an update on hormones and urogynaecology.

It has been suggested that atrophic change not only impacts the vagina but also the bladder as there are estrogen receptors present  in the trigones of the bladder. But what exactly is the role of estrogen in the bladder? Estrogen has a direct effect on detrusor function. It inhibits the movement of extra cellular calcium into the muscle cells which reduces the amplitude and frequency of spontaneous detrusor contractions and in some women can increase the bladder sensory threshold, this means without estrogen a women’s bladder capacity is reduced. It is suspected that estrogen is also involved in the micturition pathway, but what role it plays remains unclear.

As well as impacting the bladder, estrogen also has a role to play in the urethra, improving the maturation index of urethral squamous epithelium, increasing urethral closure pressure, improving pressure transmission to proximal urethra and leading to vasodilation of urethral vasculature. In collagen, estrogen has a direct effect on synthesis and metabolism in the lower genital tract.

 And what about its role in sexual function? Estrogen deficiency results in changes in urogenital anatomy leading to shortening and loss of elasticity of the vagina, increased PH, reduced secretion and thinning of vaginal epithelial layers. It can also lead to reduced nerve transmission and discharge, reduced blood flow, sleep disruption and mood alterations. It has been stated that women who report sexual dysfunction are four times more likely to have vaginal atrophy.

So how can we treat the impacts of reduced estrogen? Vaginal lubricants and moisturisers have been used in the treatment of vulvovaginal atrophy syndrome. An ongoing phase III RCT is also looking at safety and efficacy of a novel oestradiol muco-adhesive ovule/capsule which may be a future treatment option. For now vaginal lasers are also a promising outpatient treatment.  The laser has an ablative effect on the vaginal wall, triggering an improvement in collagen production within the vaginal sub mucosa. In a trial by Gabriel Femposa it was reported that 80% of women participating in the study experienced a “marked improvement in sexual response”. However some research such as Gambacccian’s study have shown that women seem to need re-treatment within a year. Data from Salvatore also suggests results are improved by combining laser with topical oestrogen compared to just laser on its own.

Estrogen has an impact in many different ways, so the real question is, is it helpful or harmful to the management of incontinence?  Meta- analysis from the HUT group and Zullio M.A et al. suggests that estrogen has a positive impact in the management of incontinence whilst data from the HERS and WHI 5yr studies suggest that the impact is negative (data from these studies should be evaluated carefully as incontinence was not a primary endpoint of either study). Overall the current consensus from those in the field is that estrogen helps sensory urgency, UTIs and Pseudo cystitis but does not improve stress incontinence.

Do you agree with the meta-analysis or the data from the RCTs? Let us know in the comment box below.