Obesity and stress urinary incontinence in women: compromised continence mechanism or excess bladder pressure during cough?

INTRODUCTION AND HYPOTHESIS

We compared two hypotheses as to why obesity is associated with stress urinary incontinence (SUI): (1) obesity increases demand on the continence system (e.g. higher cough pressure) and (2) obesity compromises urethral function and urethrovaginal support.

METHODS

A secondary analysis was performed using data from a case-control study of SUI in women. Measurements of urethrovaginal support (POP-Q point Aa, urethral axis), urethral function (maximal urethral closure pressure, MUCP), and measures of continence system demand (intravesical pressures at rest and during maximal cough) were analyzed. Cases and controls were divided into three body mass index (BMI) groups: normal (18.5-24.9 kg/m²); overweight (25.0-29.9 kg/m²); and obese (≥30 kg/m²). Logistic regression models where created to investigate variables related to SUI for each BMI group. Structural equation modeling was used to test the direct and indirect relationships among BMI, SUI, maximal cough pressure, MUCP, and POP-Q point Aa.

RESULTS

The study included 108 continent controls and 103 women with SUI. MUCP was the factor most strongly associated with SUI in all BMI groups. Maximal cough pressure was significantly associated with SUI in obese women (OR 3.191, 95% CI 1.326, 7.683; p < 0.01), but not in normal weight or overweight women. Path model analysis showed a significant relationship between BMI and SUI through maximal cough pressure (indirect effect, p = 0.038), but not through MUCP (indirect effect, p = 0.243) or POP-Q point Aa (indirect effect, p = 0.410).

CONCLUSIONS

Our results support the first hypothesis that obesity is associated with SUI because of increased intravesical pressure, which therefore increases demand on the continence mechanism.

Sling surgery for stress urinary incontinence in women: a systematic review and metaanalysis

OBJECTIVE

Understanding the long-term comparative effectiveness of competing surgical repairs is essential as failures after primary interventions for stress urinary incontinence (SUI) may result in a third of women requiring repeat surgery.

STUDY DESIGN

We conducted a systematic review including English-language randomized controlled trials from 1990 through April 2013 with a minimum 12 months of follow-up comparing a sling procedure for SUI to another sling or Burch urethropexy. When at least 3 randomized controlled trials compared the same surgeries for the same outcome, we performed random effects model metaanalyses to estimate pooled odds ratios (ORs).

RESULTS

For midurethral slings (MUS) vs Burch, metaanalysis of objective cure showed no significant difference (OR, 1.18; 95% confidence interval [CI], 0.73-1.89). Therefore, we suggest either intervention; the decision should balance potential adverse events (AEs) and concomitant surgeries. For women considering pubovaginal sling vs Burch, the evidence favored slings for both subjective and objective cure. We recommend pubovaginal sling to maximize cure outcomes. For pubovaginal slings vs MUS, metaanalysis of subjective cure favored MUS (OR, 0.40; 95% CI, 0.18-0.85). Therefore, we recommend MUS. For obturator slings vs retropubic MUS, metaanalyses for both objective (OR, 1.16; 95% CI, 0.93-1.45) and subjective cure (OR, 1.17; 95% CI, 0.91-1.51) favored retropubic slings but were not significant. Metaanalysis of satisfaction outcomes favored obturator slings but was not significant (OR, 0.77; 95% CI, 0.52-1.13). AEs were variable between slings; metaanalysis showed overactive bladder symptoms were more common following retropubic slings (OR, 1.413; 95% CI, 1.01-1.98, P = .046). We recommend either retropubic or obturator slings for cure outcomes; the decision should balance AEs. For minislings vs full-length MUS, metaanalyses of objective (OR, 4.16; 95% CI, 2.15-8.05) and subjective (OR, 2.65; 95% CI, 1.36-5.17) cure both significantly favored full-length slings. Therefore, we recommend a full-length MUS.

CONCLUSION

Surgical procedures for SUI differ for success rates and complications, and both should be incorporated into surgical decision-making. Low- to high-quality evidence permitted mostly level-1 recommendations when guidelines were possible.

Outcomes of transvaginal uterosacral ligament suspension: systematic review and metaanalysis

This systematic review of uterosacral ligament suspension provides a metaanalysis of anatomic outcomes and a summary of subjective outcomes. A successful anatomic outcome was considered present when women had "optimal" or "satisfactory" (pelvic organ prolapse quantification system stage 0 or 1) outcomes. In the anterior, apical, and posterior compartments, the pooled rates for a successful outcome were 81.2% (95% confidence interval [CI], 67.5-94.5%), 98.3% (95% CI, 95.7-100%), and 87.4% (95% CI, 67.5-94.5%). In the anterior compartment, women with preoperative stage 2 prolapse were more likely than those with preoperative stage 3 prolapse to have a successful anatomic outcome (92.4% vs 66.8%; P = .06). Outcomes, with respect to subjective symptoms, were reassuring; however, it was not possible to pool data because of methodologic differences between studies.

Self-perceived natural history of pelvic organ prolapse described by women presenting for treatment

INTRODUCTION AND HYPOTHESIS

This study aimed to describe the self-perceived natural history of pelvic organ prolapse (POP) in women seeking care.

METHODS

Women presenting to a university-based urogynecology clinic for POP (n = 107) completed a questionnaire including questions about how and when their prolapse was discovered. A urogynecologic examination including the pelvic organ prolapse quantification (POP-Q) was also performed.

RESULTS

Forty-eight percent of these women sought medical attention "immediately" after discovering a bulge. The median time to seek care was 4 months (range from 1 month to 45 years). Twenty-six percent associated their prolapse with a specific event (e.g., moving furniture or pushing a car). POP was self-discovered by 76% (81/107) of women. Self-discovered prolapses were larger than those diagnosed by physicians (Ba +1.3 vs 0.1 cm, P = .03, respectively).

CONCLUSIONS

Women seek medical advice within months of discovering their prolapse. Self-discovery is associated with higher stage prolapse than prolapse diagnosed by health care providers.

Complications requiring reoperation following vaginal mesh kit procedures for prolapse

OBJECTIVE

The objective of the study was to the characterize the symptoms and management of vaginal mesh-related complications requiring operative intervention.

STUDY DESIGN

This was a case series of patients undergoing excision of vaginal graft material. Only women who had vaginal mesh placement for the correction of pelvic organ prolapse (POP) were included. We describe the symptoms, complications, and management of women treated surgically for vaginal mesh-related complications.

RESULTS

Thirteen referred women underwent surgery for vaginal mesh-related complications. All meshes were Apogee and/or Perigee. Ten had symptomatic mesh exposures, 1 had an exposure with pelvic abscess, and 2 had pain syndromes without mesh exposure. Patients also had rectovaginal fistula, vesicovaginal fistula, recurrent POP, and persistent discharge. Five women had prior surgery for this problem. All patients underwent transvaginal mesh excision and other indicated procedures at our institution, and 6 women required a second surgery at our institution, with a median of 2 surgeries per patient.

CONCLUSION

Vaginal mesh placement for POP can be associated with pain, exposure, and fistula formation, requiring multiple operative interventions.

Pelvic architectural distortion is associated with pelvic organ prolapse

The aim of this study was to determine whether there is an association between architectural distortion seen on magnetic resonance (MR) scans (lateral "spill" of the vagina and posterior extension of the space of Retzius) and pelvic organ prolapse. Secondary analysis of MR imaging scans from a case-control study of women with prolapse (maximum point > or = + 1 cm; N = 144) and normal controls (maximum point < or = -1 cm; N= 126) was done. Two independent investigators, blinded to prolapse status and previously established levator-defect scores, determined the presence of architectural distortion on axial MR scans. Women were categorized into three groups based on levator defects and architectural distortion. Among the three groups, women with levator defects and architectural distortion have the highest proportion of prolapse (78%; p < 0.001). Among women with levator defects, those with prolapse had an odds ratio of 2.2 for the presence of architectural distortion (95% CI = 1.1-4.6). Pelvic organ prolapse is associated with the presence of visible architectural distortion on MR scans.

Age effects on internal anal sphincter thickness and diameter in nulliparous females

PURPOSE

Age can affect the delicate physiologic balance of the internal anal sphincter diameters and pressure governed by Laplace's law. This study compares the effect of aging on the internal anal sphincter thickness and diameter in younger and older nulliparous females without symptoms of fecal incontinence undisturbed by an endoanal probe.

METHODS

Magnetic resonance images were selected from a large database of nulliparous females to form two groups: "younger" females, aged 30 years and younger (n = 32), and "older" females, aged 50 years and older (n = 32). All patients were scanned without endoanal coils to allow undistorted measurement of the internal anal sphincter diameters. Inner and outer diameters were measured from axial magnetic resonance images and used to calculate sphincter thickness and mean radius by two independent investigators blinded to patient age.

RESULTS

The mean age in the younger group was 26 +/- 2.8 years, whereas that of the older group was 61.8 +/- 7.6 years. Older females had a 33 percent thicker internal anal sphincter (younger vs. older: 4.5 +/- 0.7 vs. 5.9 +/- 1 mm; P < 0.001), a 20 percent larger inner diameter (7.1 +/- 1.3 vs. 8.5 +/- 1.8 mm; P = 0.001), and a 27 percent larger outer diameter (16 +/- 2.1 vs. 20.3 +/- 3.3 mm; P < 0.001) than younger females. Neither sphincter thickness nor inner or outer diameter correlated with body mass index.

CONCLUSIONS

There is an increase in internal anal sphincter thickness, inner diameter, and outer diameter, which correlates with age in asymptomatic nulliparous females.

Vaginal birth and de novo stress incontinence: relative contributions of urethral dysfunction and mobility

OBJECTIVE

To evaluate the relative contributions of urethral mobility and urethral function to stress incontinence.

METHODS

This was a case-control study with group matching. Eighty primiparous women with self-reported new stress incontinence 9-12 months postpartum were compared with 80 primiparous continent controls to identify impairments specific to stress incontinence. Eighty nulliparous continent controls were evaluated as a comparison group to allow us to determine birth-related changes not associated with stress incontinence. Urethral function was measured with urethral profilometry, and vesical neck mobility was assessed with ultrasound and cotton swab test. Urethral sphincter anatomy and mobility were evaluated using magnetic resonance imaging. The associations among urethral closure pressure, vesical neck movement, and incontinence were explored using logistic regression.

RESULTS

Urethral closure pressure (+/-standard deviation) in primiparous incontinent women (62.9+/-25.2 cm H(2)0) was lower than in primiparous continent women (83.9+/-21.0, P<.001; effect size d=0.91) who were similar to nulliparous women (90.3+/-25.0, P=.091). Vesical neck movement measured during cough with ultrasonography was the mobility measure most associated with stress incontinence; 15.6+/-6.2 mm in incontinent women compared with 10.9+/-6.2 in primiparous continent women (P<.001, d=0.76) or nulliparas (9.9+/-5.0, P=.322). Logistic regression disclosed the two-variable model (max-rescaled R(2)=0.37, P<.001) was more strongly associated with stress incontinence than either single-variable model, urethral closure pressure (R(2)=0.25, P<.001) or vesical neck movement (R(2)=0.16 P<.001).

CONCLUSION

Lower maximal urethral closure pressure is the measure most associated with de novo stress incontinence after first vaginal birth followed by vesical neck mobility.

LEVEL OF EVIDENCE

II.

Origin and insertion points involved in levator ani muscle defects

OBJECTIVE

This project sought to identify and to describe the anatomical connections affected by levator ani defects involving the pubovisceral portion of the muscle.

STUDY DESIGN

Fourteen magnetic resonance scans of women with unilateral levator defects were selected. The missing muscle mapping technique was used to characterize the absent muscle. Normal muscle was visualized and compared with the contralateral side. Using a three-dimensional slicer, the outline of the intact muscle was traced; models of this muscle and surrounding structures were generated.

RESULTS

The missing muscle originates from the posterior pubic bone and extends laterally over the obturator internus muscle; it inserts into the vaginal wall, perineal body, and the intersphincteric space. Architectural distortion, with an asymmetric lateral spilling of the vagina was present in 50% of women. The defect was right sided in 71% of patients.

CONCLUSION

The origin and insertion points of the damaged portion of the levator ani muscle were identified.

Appearance of the levator ani muscle subdivisions in magnetic resonance images

OBJECTIVE

Identify and describe the separate appearance of 5 levator ani muscle subdivisions seen in axial, coronal, and sagittal magnetic resonance imaging (MRI) scan planes.

METHODS

Magnetic resonance scans of 80 nulliparous women with normal pelvic support were evaluated. Characteristic features of each Terminologia Anatomica-listed levator ani component were determined for each scan plane. Muscle component visibility was based on pre-established criteria in axial, coronal, and sagittal scan planes: 1) clear and consistently visible separation or 2) different origin or insertion. Visibility of each of the levator ani subdivisions in each scan plane was assessed in 25 nulliparous women.

RESULTS

In the axial plane, the puborectal muscle can be seen lateral to the pubovisceral muscle and decussating dorsal to the rectum. The course of the puboperineal muscle near the perineal body is visualized in the axial plane. The coronal view is perpendicular to the fiber direction of the puborectal and pubovisceral muscles and shows them as "clusters" of muscle on either side of the vagina. The sagittal plane consistently demonstrates the puborectal muscle passing dorsal to the rectum to form a sling that can consistently be seen as a "bump." This plane is also parallel to the pubovisceral muscle fiber direction and shows the puboperineal muscle.

CONCLUSION

The subdivisions of the levator ani muscle are visible in MRI scans, each with distinct morphology and characteristic features.

RAD9, RAD17, and RAD24 are required for S phase regulation in Saccharomyces cerevisiae in response to DNA damage

We have previously shown that a checkpoint dependent on MEC1 and RAD53 slows the rate of S phase progression in Saccharomyces cerevisiae in response to alkylation damage. Whereas wild-type cells exhibit a slow S phase in response to damage, mec1-1 and rad53 mutants replicate rapidly in the presence or absence of DNA damage. In this report, we show that other genes (RAD9, RAD17, RAD24) involved in the DNA damage checkpoint pathway also play a role in regulating S phase in response to DNA damage. Furthermore, RAD9, RAD17, and RAD24 fall into two groups with respect to both sensitivity to alkylation and regulation of S phase. We also demonstrate that the more dramatic defect in S phase regulation in the mec1-1 and rad53 mutants is epistatic to a less severe defect seen in rad9 delta, rad 17 delta, and rad24 delta. Furthermore, the triple rad9 delta rad17 delta rad24 delta mutant also has a less severe defect than mec1-1 or rad53 mutants. Finally, we demonstrate the specificity of this phenotype by showing that the DNA repair and/or checkpoint mutants mgt1 delta, mag1 delta, apn1 delta, rev3 delta, rad18 delta, rad16 delta, dun1-delta 100, sad4-1, tel1 delta, rad26 delta, rad51 delta, rad52-1, rad54 delta, rad14 delta, rad1 delta, pol30-46, pol30-52, mad3 delta, pds1 delta/esp2 delta, pms1 delta, mlh1 delta, and msh2 delta are all proficient at S phase regulation, even though some of these mutations confer sensitivity to alkylation.