BERKELEY, CA (UroToday.com) - Obesity is one of the important risk factors for the development of urinary incontinence with old age, vaginal delivery, history of gynecological surgery, higher body mass index, menopausal status, smoking, and coffee and alcohol consumption.(1,2)
However, all cases of SUI are not associated with obesity, thus the clinical characteristics and urodynamic parameters might be different between obese and non-obese SUI patients. Although transobturator tape (TOT) became a mainstay of SUI surgery, very little data has been available for assessing the impact of obesity on TOT procedure. Therefore, we investigated the influence of obesity on the clinical characteristics, quality of life (QoL) and outcomes in stress urinary incontinence patients who underwent TOT surgery.
Medical records of SUI patients who underwent TOT operations from January 2007 to February 2009 were retrospectively reviewed. The patients who had any possible conditions that might affect the urinary function - such as neurologic disease, urinary tract infection or urolithiasis were excluded, and a total 107 patients were enrolled. The operation was carried out with the outside-in obturator tape (Iris-TOT, Dow Medical), under intravenous propofol infusion with local infiltration of bupivacaine. General or spinal anesthesia was performed when the patient refused the intravenous anesthesia. A Foley catheter was removed the morning of the next day. All patients were evaluated by history taking into account such factors as the severity of urinary incontinence, parity, pelvic organ surgery history, and bladder irritative symptoms. To obtain health-related quality of life (QoL) assessments, patients were asked to complete the King’s Health Questionnaire (KHQ). Statistical analysis was performed using the Mann-Whitney U-test for parametric continuous variables, and linear-by-linear association or Fisher exact test for nonparametric variables. Statistical program was the Statistical Package for Social Sciences, version 12.0 software (SPSS, Chicago, IL, USA). A p-value <0.05 was considered statistically significant.
Of the 107 patients, 55 (51.4%) were normal weight women and 52 (48.6%) were obese women. Obese patients showed higher severity grade of urinary incontinence than the non-obese group (grade I 89.1%, II 9.1% and III 1.8% in non-obese group, grade I 65.4%, II 30.8% and III 3.8% in obese group, p=0.007). Urethral hypermobility was observed more frequently in obese patients than non-obese (31 (59.6%) vs. 22 (40%), p=0.034). Obese patients had worse preoperative urge and urge incontinence perception scale than non-obese (p=0.043, p=0.003, respectively). On 3-day frequency-volume chart, obese patients tended to void more frequently than non-obese patients, but it did not show a significant difference (9.93±2.46 vs. 8.98±2.78 per day, p=0.072). No differences in nocturia and functional bladder capacity were noted between the two groups (each p>0.05). The overall subjective cure, improvement, fail and recurrence rates were 85.5%, 7.3%, 3.6% and 3.6% in the non-obese group, and 86.5%, 3.8%, 3.8% and 5.8% in the obese group, respectively. De novo urgency was observed in 2 (3.6%) patients in the non-obese group, and 4 (7.7%) in the obese group (p>0.05). Patients who had taken anticholinergics postoperatively because urinary frequency or urgency symptoms were sustained even after operation, were 11 (20.0%) and 6 (11.5%) in the non-obese and obese group, respectively (p>0.05).
Although obesity is a well-established risk factor for the development of SUI and could impact on voiding pattern, the exact mechanism is not clear. Higher intra-abdominal pressures have been observed in patients with greater BMI, and it may stress the pelvic floor secondary to a chronic state of increased pressure.(3) Our data showed obese patients had worse grades of SUI, urgency and urge incontinence perception scale than non-obese, and it was consistent with previous studies. In contrast to previous reports however, no differences were founded in VLPP (data are not shown) and incidence of intrinsic urethral sphincter dysfunction between the obese and non-obese group. We believe that obesity was defined by a BMI of 30 or greater in their western population, and it might make a difference in the results. So far, only one study was reported for the relationship of obesity and TOT outcomes. Rechberger et al. conducted 269 retropubic and 268 transobturator sling procedure, and demonstrated that BMI does not influence the clinical effectiveness of SUI treatment.(4) However, they did not access the voiding symptom, and we believe the retropubic approach could lead to a greater chance of de novo urgency. This was confirmed by Sung et al. They performed a meta-analysis of TVT and transobturator approach studies and concluded the transobturator sling operation had a lower risk (OR 0.54) of de novo bladder voiding symptoms than TVT.(5) Consistent with the previous study, our data revealed that only 2 (3.6%) patients in the non-obese group and 4 (7.7%) in the obese group complained of de novo urgency without significant difference.
Obese SUI patients had worse grades of SUI, urgency and urge incontinence perception scale, and higher incidence of urethral hypermobility than non-obese SUI patients. However, QoL by KHQ, incidence of intrinsic urethral sphincter deficiency, outcomes, recurrence rate and complications of TOT procedure did not demonstrate the difference. Based on the results of this study, the TOT operation can be applied even in obese SUI patient with high expectation, although longer follow-up is needed.
- Parazzini F, Colli E, Origgi G, Surace M, Bianchi M, Benzi G, et al. Risk factors for urinary incontinence in women. Eur Urol 2000;37:637-43
- Park YK. Female Stress Urinary Incontinence. J Korean Continence Soc 2008;12:1-9
- Noblett KL, Jensen JK, Ostergard DR. The relationship of body mass index to intra-abdominal pressure as measured by multichannel cystometry. Int Urogynecol J Pelvic Floor Dysfunct 1997;8:323-6
- Rechberger T, Futyma K, Jankiewicz K, Adamiak A, Bogusiewicz M, Skorupski P. Body mass index does not influence the outcome of anti-incontinence surgery among women whereas menopausal status and ageing do: a randomised trial. Int Urogynecol J Pelvic Floor Dysfunct 2010
- Sung VW, Schleinitz MD, Rardin CR, Ward RM, Myers DL. Comparison of retropubic vs transobturator approach to midurethral slings: a systematic review and meta-analysis. Am J Obstet Gynecol 2007;197:3-11
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