Role of fascial collagen in stress urinary incontinence

OBJECTIVES: Our purpose was to determine whether collagen of the pubocervical fasciae that support the urethrovesical junction undergoes alterations that might contribute to incontinence. STUDY DESIGN: Pubocervical fascia was collected as a residual tissue in 82 patients, aged 25 to 73 years, during surgical treatment of cystocele (n = 26, no incontinence) or of stress urinary incontinence (n = 56). Measurements were made of collagen content, solubility, and cross-linking and of collagenase activity. RESULTS: Patients treated for incontinence had the same mean age and parity as the control cystocele group. There was a highly significant (20%, P <.0005) decrease in collagen content in fascial tissue from incontinent women. There was no difference in the percentage of acid-soluble (0.7%) and pepsin-soluble (17%) collagen in the 2 groups of patients; this agrees with the lack of significant change in the degree af collagen cross-linking by pyridinoline. Collagenase activity was significant in fascia but did not change in incontinence. Incontinent women had an increased body mass index. CONCLUSIONS: The pubocervical fasciae of incontinent women show a diminished content of collagen,but this is not accompanied by changes in collagen solubility or cross-linking or in collagenase activity. This decrease in collagen may contribute to the weakening of support of the bladder neck.