Role of fascial collagen in stress urinary incontinence

Our purpose was to determine whether collagen of the pubocervical fasciae that support the urethrovesical junction undergoes alterations that might contribute to incontinence.

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.

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 of 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.

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.