Artificial urinary sphincter for post-prostatectomy incontinence: impact of prior collagen injection on cost and clinical outcome.

PURPOSE: We retrospectively reviewed our experience with the artificial urinary sphincter in men with post-prostatectomy incontinence to determine the impact of prior collagen injection therapy on surgical outcome and overall cost of treatment.
MATERIALS AND METHODS: The records and preoperative urodynamic studies of 30 men with post-prostatectomy incontinence who underwent artificial urinary sphincter placement were reviewed. Of these patients 23 (76.6%) had undergone prior collagen injection (collagen group) and 7 had not (noncollagen group). Preoperative and postoperative severity of incontinence was assessed with the American Urological Association quality of life index (scale 0 to 6) and number of pads used daily. Using a Valsalva leak point pressure of less than 60 cm. water as a predictor of failure with collagen injection, we calculated the potential savings had these patients foregone collagen injection and chosen artificial urinary sphincter primarily.
RESULTS: Of the 30 patients 24 (80%) were incontinent following radical retropubic prostatectomy and 6 (20%) after transurethral resection. Intrinsic sphincter deficiency was the sole etiology of incontinence in most patients (83.3%) and 5 (16.7%) had concomitant detrusor instability. Six patients alternated the use of pads with the use of clamps or a condom catheter to aid in controlling leakage. Mean number of collagen treatment sessions for the injection group was 2.9 (range 1 to 7). There was a significant difference in mean time from prostatectomy to artificial urinary sphincter between the noncollagen (25.3 months) and collagen (35.8 months) groups (p = 0.04). There were no other statistically significant differences between the groups, including mean age (66.2 years, range 45 to 83), mean followup (26.2 months), mean preoperative pads daily (5.8+/-3.4), median preoperative quality of life index (6, range 3 to 6), median preoperative American Urological Association symptom score (13, range 3 to 35) and mean preoperative Valsalva leak point pressure (42.7+/-21.4 cm. water). For all patients in the study the mean postoperative pads daily was 0.8, mean quality of life index 1 and surgical complication rate 13.3%. There were no statistically significant differences between the collagen and noncollagen groups in any of these parameters. Among the collagen group 17 patients (73.9%) had a Valsalva leak point pressure less than 60 cm. water. Considering the mean additional period of incontinence (time between prostatectomy and artificial urinary sphincter) to be 12.9 months and the additional treatment costs (including pads daily and mean number of collagen syringes per patient), the direct costs of treatment for the collagen group were 85.6% higher than those for patients who chose artificial urinary sphincter primarily.
CONCLUSIONS: Prior collagen therapy did not adversely influence the surgical complication rate or compromise effectiveness of the artificial urinary sphincter. However, patients with Valsalva leak point pressure less than 60 cm. water have lower rates of success with collagen injection therapy and could benefit from a more successful, timely and cost-effective treatment of incontinence by choosing the artificial urinary sphincter as primary therapy.