Hypothesis / aims of study
World Health Organizartion (WHO) define elderly people as those with ages between 75 and 90 years old. The prevalence of stress urinary incontinence (SUI) increases with age and is very common in this age range. Single incision slings (SIS) are designed not only to maintain efficacy but also to reduce operation times, analgesic requirements and complications.
The objective of our study was to analyze long-term efficacy and safety of single incision sling (ALTIS®) in old women suffering SUI.
Study design, materials and methods
This is a prospective, observational single center study based in patients with SUI who underwent single incision sling surgery with ALTIS® device with at least 1 year follow up. All participants provided written informed consent prior to enrolment. Urodynamic study was performed in all women before surgery. We excluded patients with neurogenic SUI, previous vaginal surgeries and those with urgency incontinence as the main symptom. Therefore, we included patients with SUI or with mixed urinary incontinence when SUI was predominant. Objective cure was defined as ICIQ-SF=0 or office negative stress test. Subjective cure was evaluated with a satisfaction visual analogic scale (0-10). Safety was analyzed according to Clavien-Dindo classification. Patients were stratified according to age in young adults (<60 years old) old adults (60-74 years old) and elderly people (75-90 years old). To compare variables we performed ANOVA and Chi Square test. Kaplan Meyer test was used to analyze the evolution of continence according during follow up. All statistical analysis were performed with SPSS®21 (Mac version). For being able to detect differences between groups sample size was calculated with the program R to achieve a power of 80%.
We included 110 consecutive women between 2014 and 2017. Distributed by age, 61 were young adults (55,5%), 37 were old adults (33,6%) and 12 were elderly patients (10,9%). There were no differences in Body Mass index, number of vaginal deliveries or previous urgency symptoms between groups (p=0,23).
With a mean follow up of 32,6 months (range 12-66) global success rate was 86,4% at the end of follow up. Kaplan Meyer test found no differences between groups in objective cure rates at the end of follow up (93,45 vs 86,51% vs 88%% log rank=0,57). Satisfaction was globally high with an average score of 9,58 (SD 0,7) but elderly people were significantly less satisfied than non-elderly patients (9,67 vs 9,67 vs 9. p=0,04) at the end of follow up. These results are summarized in table 1 and figure 1.
Regarding complications there were no differences between groups in pain, urinary tract infection or voiding dysfunction. No cases of tape erosion were found. However, de novo urgency was higher in elderly people compared to non-elderly people (45% vs 4% p=0,001).
Interpretation of results
Even though SUI increases with age (1), it seems that less elderly people seek for help about this issue maybe due to fear of a surgical procedure. There are several studies regarding surgical treatments for pelvic floor disorders, and specifically trans-obturator slings, with good results in elderly women (2). When offering this surgery to elderly patients we can reassure them about the same effectiveness compared to younger patients. Nevertheless we have found a prevalence of the novo urgency in up to 45% in elderly women compared to a 4% in non-elderly patients. For mini-slings it is described an incidence of de novo urgency near to 10% (3). How can we explain the higher incidence of de novo urgency in elderly women?. As detrusor overactivity prevalence increases with age, maybe the detrusor of elderly patients responds with overactivity to the insertion of a mid-urethral sling in a higher proportion of patients compared to non-elderly ones. On the other hand, when operating these patients we can somehow produce a mild obstruction to a more fragile detrusor, and detrusor overactivity arises. One weakness of our study is the lack of postoperative urodynamic study in patients with de novo urgency. Despite for academic purposes it could be recommendable, clinically, this de novo urgency didn’t alter quality of life in our study (in fact satisfaction visual analogic scale score in elderly women was 9 out of 10) and that is why we didn’t perform postoperative urodynamic study. Other studies found increased risk of transient postoperative voiding difficulty. Nevertheless, in our study we didn’t find differences in voiding symptoms between young and elderly women. Anyway it is remarkable that satisfaction rate is very high in this range of age, and so, surgery might be offered to old patients when SUI appears.