Surgical Management of SUI Component of Mixed Incontinence in Elderly

The demographic pyramid is currently being reshaped by an aging population.¹  Classically, the term "elderly" refers to the age group above 60 years old.² However, when referring to urinary incontinence, most studies establish a cut-off value at 70 years old.³ Currently, the overall prevalence of urinary incontinence is estimated at 8.7%.⁴ Mixed urinary incontinence (MUI) on the other hand, defined as the presence of stress urinary incontinence and overactive bladder symptoms, is a common condition in women over 60 years old, with a prevalence of 31%.⁵ The presence of overactive bladder symptoms is higher in older women than in younger women, with a 10-fold increase with age.⁵ Therefore, we can expect a continuous increase in the number of consultations for this reason.

Today, there is still no consensus on the best therapeutic approach for MUI, whether initially treating the urgency component and reserving surgical management for later or vice versa. However, there is ample support in the literature for improvement in urgency symptoms with mid-urethral sling (MUS), with a potential 30-50% symptomatic relief of overactive bladder symptoms in patients with MUI.⁶ However, in this group of women, it is necessary to consider some relevant aspects regarding the results and complications of MUS:

• Persistent or de novo overactive bladder symptoms after mid-urethral sling placement increase with age.^7,8,9
• Surgical complications during surgery and shortly after are more frequent, with a higher rate of vesical and vaginal perforation, intermittent catheterization, and urinary tract infections.^7,8,9
• Although randomized studies have shown that urodynamic parameters lack the ability to predict success and outcomes in patients undergoing MUS procedures in the general population, it is in this patient subgroup (elderly women) where variables such as lower urinary flow rate, higher post-void residual, reduced maximum cystometric capacity, and lower maximum urethral closure pressure have been observed.⁹ These variables have been associated with a higher number of voiding disorders.
• The urogenital atrophy that characterizes the normal aging process in women may be associated with a higher risk of mesh exposure. However, this has not been demonstrated in clinical studies.⁸

Elderly patients may be more prone to overlook or disregard mesh exposure.⁹ The use of local estrogens has not been shown to have better results in this group.¹⁰ In any case, there are no high-quality studies focused on this outcome. Despite this, it is imperative that patients are adequately informed about these possible complications, especially in sexually active patients.

Currently, there is no consensus on which mid-urethral sling is better in elderly women with mixed urinary incontinence. However, given the low rate of surgical complications and scarce but growing evidence suggesting that the transobturator route is better in improving overactive bladder symptoms in women with MUI over the retropubic route,⁶ the transobturator route could be considered as the preferred route in this subgroup. This is undoubtedly an area that requires further studies to confirm or deny this recommendation.

In conclusion, regardless of the preferred midurethral sling type, or whether it is performed before or after medical management of the overactive bladder, the benefit of mid-urethral slings in elderly patients with mixed urinary incontinence is clear. However, these patients require a more thorough evaluation, which should include a multichannel urodynamic study, to minimize the number of voiding complications and provide adequate data to better inform our patients with regard to the overall success of the surgery.  

REFERENCES

1. Envejecimiento | Naciones Unidas [Internet]. United Nations. United Nations; [cited 2023Apr27]. Available from: https://www.un.org/es/global-issues/ageing
2. Older persons [Internet]. UNHCR. [cited 2023Apr27]. Available from: https://emergency.unhcr.org/protection/persons-risk/older-persons
3. Ellington DR, Erekson EA, Richter HE. Outcomes of surgery for stress urinary incontinence in the older woman. Clinics in Geriatric Medicine. 2015;31(4):487–505. 
4. Milsom I, Gyhagen M. The prevalence of urinary incontinence. Climacteric. 2018;22(3):217–22.
5. Abufaraj M, Xu T, Cao C, Siyam A, Isleem U, Massad A, et al. Prevalence and trends in urinary incontinence among women in the United States, 2005–2018. American Journal of Obstetrics and Gynecology. 2021;225(2). 
6. Tahseen S, Reid P. Effect of transobturator tape on overactive bladder symptoms and urge urinary incontinence in women with mixed urinary incontinence. Obstetrics & Gynecology. 2009;113(3):617–23. 
7. Groutz A, Levin I, Gold R, Pauzner D, Lessing JB, Gordon D. “Inside-out” transobturator tension-free vaginal tape for management of occult stress urinary incontinence in women undergoing pelvic organ prolapse repair. Urology. 2010;76(6):1358–61. 
8. Engen M, Svenningsen R, Schiøtz HA, Kulseng-Hanssen S. Mid-urethral slings in Young, middle-aged, and older women. Neurourology and Urodynamics. 2018;37(8):2578–85.
9. Yao J, Tse V. Twenty-five years of the MIDURETHRAL sling: Lessons learned. International Neurourology Journal. 2022;26(2):102–10. 
10. Cadish LA, West EH, Sisto J, Longoria T, Bebchuk JD, Whitcomb EL. Preoperative vaginal estrogen and midurethral sling exposure: A retrospective cohort study. International Urogynecology Journal. 2015;27(3):413–7.