Penile prosthesis patients tend to be older than before

June 1, 2006

Atlanta-The population of patients being treated with a penile prosthesis for erectile dysfunction is evolving, with the average patient now being older and having more medical comorbidities compared with less than 20 years ago, according to the results of a nationwide epidemiologic study reported at the annual AUA meeting here.

The analyses were performed by University of Michigan urologists using the Nationwide Inpatient Sample database, which represents a 20% stratified sample of annual hospital discharges in the United States. Data were extracted for over 29,000 patients discharged between 1988 and 2002 with an ICD-9 procedural code for insertion of a penile prosthesis. The men were divided into tertiles based on year of discharge (1988 to 1992, 1993 to 1997, and 1998 to 2002), and various characteristics of the subgroups were compared using appropriate statistical methods.

From the first to the last period, the researchers observed an increase in mean patient age and in the proportion of patients with significant medical comorbidities, defined as a Charlson Index score of 2 or greater. Mean age was 60.26 years for men in the earliest tertile and increased to 62.51 years in those operated on most recently, and the proportion of men with a Charlson Index score of 2 or greater doubled from the first to the last tertile, increasing from 20.5% to 39.6%. For both of those variables, the difference between the earlier and later subgroups was statistically significant.

"The findings in this study may also reflect a greater comfort with penile prosthesis surgery among urologists," Dr. Schuster said, "and acceptance that men should not be excluded from having an active sex life because they have multiple comorbidities. We expect that as ED continues to be talked about more, urologists will be seeing more and more complex patients who have failed or have contraindications for pharmacological therapy and are candidates for more invasive interventions."

Usage among minorities

The study also evaluated temporal trends in a number of other patient-and procedure-related features. Other significant changes found included an increase over time in the proportion of racial minorities receiving a penile prosthesis. Minorities accounted for 17% of the population during the first 5 years of the study period compared with 33.3% during the last 5 years. In addition, comparing those two time periods, the proportion of inflatable penile prostheses placed increased significantly from 71.1% to 88.4%.

"There is no apparent explanation for the increase in racial minorities represented among the recipients of a penile prosthesis. However, we believe the increase in the use of the inflatable prosthesis represents infusion of the technology as more residents trained in that procedure have gone on into practice and are comfortable implanting this type of device," Dr. Taub said.

The researchers studied factors associated with prosthesis type. The results of the multivariate analysis showed that factors associated with an increased likelihood of receiving an inflatable prosthesis versus a malleable device included higher income, private insurance, Caucasian race, and having the procedure performed at a high-volume hospital.

"It is not possible to tell from the data available whether these features might reflect access to care, ease of use, or have some other explanation. However, we hope to investigate this issue further using data from our own institution," Dr. Taub said.

Analysis of hospital data showed the mean length of stay fell by nearly half during the study period, from 2.86 days during the first 5 years to 1.54 days during the last 5 years. That change was also statistically significant.