Followup of intraurethral collagen for female stress urinary incontinence

Purpose: We studied patient selection parameters and durability of response of collagen injections for female stress incontinence. Materials and Methods: A total of 187 women 15 to 87 years old (mean age 63) underwent collagen injections for urethral incompetence. Treatment outcome was determined by a change in individual incontinence grades before and after injection. Results: Of the 187 women 43 (23%) were cured and 97 (52%) improved, while injection failed in 47 (25%). Mean followup in the successful (cured or improved) group was 22 months (range 4 to 69) after the last collagen injection. No difference in outcome was noted in relation to patient age or pretreatment grade of incontinence. Of the 31 patients with bladder instability 13 (42%) had a favorable outcome. No significant difference in outcome was noted in patients with or without hypermobility (p = 0.21235). Patients with type 3 incontinence required the largest amount of collagen for a successful outcome. Persistence of continence in 80 patients who were cured for at least 2 months was plotted on a Kaplan-Meier survival curve. The probability of remaining dry without additional collagen was 71, 58 and 46% at 1 to 3 years, respectively. Conclusions: Intraurethral collagen is a safe and well tolerated procedure. Pretreatment bladder instability may be an adverse factor. Patients with or without hypermobility had equal benefit. Long-term durability was noted. If deterioration occurred, repeat collagen injections restored success.