In order to perform such an analysis, we utilized the Healthcare Cost and Utilization Project State Inpatient and State Ambulatory Surgery databases for Florida from 2006 to 2015 to assess for risk-adjusted predictors of prosthesis implantation and greater time in between RP and penile prosthesis. This dataset uses claims-based data and unique linkage variables to follow patients across various clinical settings within the state of Florida. Patients were included if they had a claim for RP (performed for prostate cancer). Patients were subsequently tracked and any with a subsequent claim for penile prosthesis implantation during the study interval was noted. Patients undergoing RP in the last three years of the study interval were excluded so as to allow sufficient lag time for penile prosthesis implantation.
Baseline characteristics were recorded including age, race/ethnicity, insurance provider, home zip code-based income quartile, and medical comorbidities. These factors were compared between patients who did and did not undergo penile prosthesis using descriptive statistics, and a multivariable logistic regression model adjusting for possible confounding variables was used to determine risk-adjusted predictors of penile prosthesis implantation. We also performed a quartile-based analysis of time between RP and prosthesis in which patients with the highest quartile of time were compared to those with the lowest to determine predictors of longer duration between the surgeries.
In total, we identified 29,288 men who underwent RP with 1,449 (4.9%) undergoing subsequent prosthesis after a median of 2.1 years. Predictors of penile prosthesis included open RP (OR 1.5, p< 0.01), African American race (OR 1.7, P <0.01), Hispanic ethnicity (OR: 3.2, P < .01), and Medicare insurance (OR: 1.4, P < .01). Older patients (age >70 years; OR: 0.7, P < .01) and those with higher income (OR: 0.8, P < .05) were less likely to be implanted. Predictors of longer time to implantation included open RP (OR: 1.78, P < .01), laparoscopic RP (OR: 4.67, P < .01), Medicaid (OR: 3.03, P < .05), private insurance (OR: 2.57, P < .01), and greater income (OR: 2.52, P < .01).
Overall, our findings highlight that only a small subset of patients undergo penile prosthesis implantation following RP, despite studies reporting high rates of worsened erections relative to preoperative function.1 While African American race and Hispanic ethnicity have been previously associated with increased rates of penile prosthesis implantation, ours is the first contemporary study to suggest increased rates of implantation among men who underwent open RP relative to robotic, and among men with Medicare relative to other insurances in the post-RP population.2 Furthermore, our study is the first to identify predictors of longer time between RP and prosthesis implantation, including greater income, Medicaid/private insurance and history of open/laparoscopic RP. The rationale behind these findings remains to be elucidated, but these data clearly merit further investigation. It is worthy of noting that there are methodological concerns with the use of quartile-based time and income analysis, however, the purpose of these analyses was not to establish causality, but rather to determine if there was any suggestion of a relationship which might merit more robust analysis in the future. These findings, which shed light on possible healthcare disparities within the treatment of post-RP ED, may be used for patient counseling or to generate hypotheses for further studies. Future studies should also assess the efficacy of prospective patient education programs targeted at those patients at greatest risk for lost quality of life years related to suboptimal ED treatment.
Written by: Petar Bajic, MD, Fellow, Andrology & Male Genital Reconstruction, Rush University Medical Center, Chicago, Illinois.
- Nelson, Christian J., Peter T. Scardino, James A. Eastham, and John P. Mulhall. "Back to baseline: erectile function recovery after radical prostatectomy from the patients' perspective." The journal of sexual medicine 10, no. 6 (2013): 1636-1643.
- Tal, Raanan, Lindsay M. Jacks, Elena Elkin, and John P. Mulhall. "Penile implant utilization following treatment for prostate cancer: analysis of the SEER-Medicare database." The journal of sexual medicine 8, no. 6 (2011): 1797-1804.