The use of treatments for erectile dysfunction among survivors of prostate carcinoma

Authors


Abstract

BACKGROUND

The objectives of this survey were to describe the prevalence of using a treatment for erectile dysfunction (ED) among men after therapy for localized prostate carcinoma and to construct models explaining the variance in trying a treatment, treatment success, and adherence to treatment.

METHODS

A postal survey was sent to 2636 men in The Cleveland Clinic Foundation's Prostate Cancer Registry who were treated initially with either definitive radiotherapy or prostatectomy for localized prostate carcinoma. The survey asked about demographic items, past and current sexual functioning, and the partner's sexual function. Men were asked about their current and intended use of medical treatments for ED. Standardized questionnaires included the Sexual Self-Schema Scale-Male Version, the International Index of Erectile Function, urinary and bowel symptom scales from the Los Angeles Prostate Cancer Index), and the Short-Form Health Survey.

RESULTS

The return rate was 49%. Differences between men who returned the questionnaire and men who did not respond suggest that the sample was weighted toward men who were more interested in staying active sexually. ED was a problem for 85% of men, and 59% of this group used at least 1 treatment for ED. Only 38% of men found that a medical treatment was at least somewhat helpful in improving their sex lives, however, and 30% of respondents still were using at least 1 treatment at the time of the survey. Factors that were associated with the efficacy of treatments for ED and with their continued use included having a sexual partner, younger age, choosing a treatment for prostate carcinoma that was more likely to spare some sexual function, and not having had neoadjuvant or current antiandrogen therapy. Men who tried a greater number of treatments for ED were more likely to find one that worked. Men were more likely to continue using treatments for ED that produced greater improvements in sexual function.

CONCLUSIONS

The success of medical treatments for men with ED among long-term survivors of prostate carcinoma is limited. Men prefer noninvasive treatments, although invasive treatments are more effective. Sexual counseling for men and their partners is recommended, because it may increase the use of medical therapies for ED. Creating more realistic expectations in both partners also may enhance treatment adherence. Cancer 2002;95:2397–407. © 2002 American Cancer Society.

DOI 10.1002/cncr.10970

Treatments for patients with localized prostate carcinoma leave many men with organic erectile dysfunction (ED), so that restoring sexual satisfaction requires a medical treatment for ED. Although such treatments have become widely available, men's long-term satisfaction and adherence to using them after treatment for prostate carcinoma rarely have been investigated.

There is minimal literature on men's use of medical treatments for ED of unselected etiology. Focus groups suggest that men with ED desire a treatment that will restore firm erections, increase their sexual pleasure, and satisfy their partner. They do not want invasive treatments or treatments with negative side effects.1 An effective oral medication matches these criteria most closely. Unfortunately, the most effective oral medication currently on the market, sildenafil (Viagra®), has limited success after treatment for prostate carcinoma. After radical prostatectomy, 29–53% of men report a positive response.2–6 Men who are younger, who undergo bilateral nerve-sparing surgery, and ware are at least 1 year postsurgery are more likely to fall into this group.3–6 The positive response rate to sildenafil after radiation therapy for localized prostate carcinoma varies from 50% to 91%, with higher success rates reported among men who received brachytherapy.7–11 Such statistics sound promising, but most studies define a positive response as any statistically significant improvement in erection quality over baseline. Follow-up periods in those studies were brief. Case series that used the ability to have intercourse consistently over several weeks as the outcome criterion reported much lower success rates compared with other series.2, 5, 6, 8, 10, 11 In general, sildenafil is most effective in men who have psychogenic ED or only a mild, organic deficit in penile rigidity.12, 13 Its efficacy also clearly is better in men who have a greater degree of recovery of tumescence after treatment for prostate carcinoma.6, 8, 11 Data on adherence to sildenafil beyond the first month or two of use in large community populations are not yet available, but anecdotal sales reports suggest that 50% of men do not renew prescriptions for sildenafil.14

Although oral medication is the least invasive therapy for men with ED, patient satisfaction reportedly was highest for the most invasive treatment—the inflatable penile prosthesis: Typically ≈ 75% of men report that they are sexually active and satisfied after a prosthesis.15–17 However, as reversible therapies, such as penile injections and vacuum devices became available, the numbers of penile prosthesis surgeries decreased dramatically.15, 16 Satisfaction with a penile prosthesis appears similar in men who have had prostate carcinoma and men with other causes for their erection problems.18, 19

By comparison, treatments of intermediate invasiveness have been less successful. Recent reports on the long-term follow-up of men who tried penile injections concur that about 50% stopped using the treatment within the first year, and further attrition over time left approximately one-third of men satisfied with the treatment in the long term.20, 21 Intraurethral delivery of prostaglandin E1 was far less effective compared with injections22, 23 and is unlikely to help many men with erection problems after prostate carcinoma. The vacuum constriction device reportedly was less popular than penile injections with men seeking help from ED clinics.24–26 In a randomized trial of injections compared with the vacuum device using a cross-over design, 57% of men preferred penile injections at follow-up, whereas 27% of men still were using the vacuum device, and 14% of men alternated between the two methods.27 Men who were age < 60 years, had suffered for less than 1 year with the sexual problem, or had undergone radical prostatectomy were the most likely to prefer penile injections.

In general, outcome studies in ED clinics suggest that, despite trying a mean of 2 treatment modalities, only 30–40% of men were active sexually and considered their problem resolved by 1–5 years after their initial evaluation.24–26 Emotional factors, such as the loss of a partner, longing for more spontaneity, or relationship conflict, are key reasons that men stop using medical therapies.16, 21 The few programs that combine counseling with medical therapies may achieve enhanced satisfaction rates.28, 29 Men who present to clinics for help with erection problems may represent a more emotionally distressed subset of all men with ED. Patients in an ED clinic reported more impairments in mental health compared with impairments in the physical health aspects of quality of life.30 Now that sildenafil is prescribed increasingly by primary-care physicians, a larger and more diverse population of men may try it, although even fewer of them are likely to request or receive sexual counseling as part of their treatment plan for ED. To better understand men's use of medical treatments for ED after prostate carcinoma, we undertook a large, retrospective survey of the Prostate Cancer Registry at The Cleveland Clinic Foundation, which provided us with a group of consecutive men who were treated definitively for localized prostate carcinoma either with surgery or radiation therapy.

MATERIALS AND METHODS

Patients

Our patient population and survey methods have been described in detail in a previous publication31 and are summarized briefly here. At the time of our survey, the Prostate Cancer Registry of The Cleveland Clinic Foundation included 2636 men who were treated initially with definitive therapy for localized disease, including 1207 men postradical prostatectomy and 1429 men postdefinitive radiation therapy. The earliest year of treatment in the registry was 1986; however, the majority of men (90%) were treated between 1992 and 1999. The registry included 16% African-American men (n = 427 patients). Almost all of the remaining men were white. Information recorded in the registry included age, ethnicity, time since prostate carcinoma treatment, clinical tumor stage, pretreatment sexual potency (noted as yes or no by the physician), the use of nerve-sparing surgery for radical prostatectomy (defined by chart review), radiation therapy technique, current status (free of disease or in biochemical failure; defined by prostate specific antigen serum [PSA] level), and initial use of neoadjuvant hormone therapy. Current use of antiandrogen therapy was ascertained by self-report on our survey.

Data Collection

Men were mailed a questionnaire with a cover letter explaining the research and elements of informed consent. Returning the survey constituted proof of informed consent. The survey was not anonymous, because we wanted to link questionnaire responses with the registry information. The study was approved by the Institutional Review Boards of The Cleveland Clinic Foundation and The University of Texas M. D. Anderson Cancer Center. Men who did not return the initial questionnaire within 1 month received one reminder letter. Respondents received a booklet of United States Prostate Cancer Awareness postage stamps, worth $6.60, as a small incentive.

Measures

The questionnaires included items on demographic background and medical history. Men were asked about erectile function during the year before they were diagnosed with prostate carcinoma, about the influence of a desire to maintain sexual function on their choice of treatment for prostate carcinoma, and changes in erectile function and sexual satisfaction as a result of treatment. Problems in the partner's sexual function were assessed. Men were asked separately whether they ever sought help for a sexual problem before they were diagnosed with prostate carcinoma, during treatment, within the first year after treatment, or more recently. All current treatments for ED were listed. For each treatment, men were asked whether they would like to try it or had tried it and, if they had tried it, to rate its impact on their sex life and indicate whether they still were using it.

The survey instrument also included several standardized questionnaires, including the Sexual Self-Schema Scale-Male Version (SSSS-M),32 which measures a generalized positive versus negative view of oneself as a sexual person, and the International Index of Erectile Function (IIEF),33 which assesses erectile function, orgasmic function, sexual desire, intercourse satisfaction, and overall sexual satisfaction within the past 4 weeks. To have a measure of sexual function in men who were not on treatment compared with men who currently were using a medical treatment for ED, we asked men to indicate their use of ED treatments during a 4-week reference period. We also included the urinary and bowel symptom scales from the Los Angeles Prostate Cancer Index (PCI)34 and the Short Form Health Survey (SF-36) to measure health-related quality of life.35

Statistical Analysis

All statistical analyses were performed using SAS software (SAS, Inc., Cary, NC). Univariate statistical analyses were conducted to describe the demographic characteristics and medical treatment history of the sample of men who were contacted to participate in the survey. Descriptive statistics, including frequencies, means, and standard deviations, were calculated when appropriate. T tests and chi-square analyses were conducted to compare survey respondents with nonrespondents with regard to demographic characteristics and medical treatment history.

Among the survey respondents, psychometric analyses were conducted on scale scores when appropriate (e.g., SSSS-M, IIEF, PCI, and SF-36 scales); Cronbach α estimates for scoring of each measure exceeded 0.75, the generally accepted level that indicates acceptable internal consistency for a given population. Scale scores were estimated for individuals who provided responses to at least 90% of the items underlying a given measure, unless specified differently in the instrument's original scoring guidelines. Scoring was conducted under the assumption of a consistent response pattern to the items in each index.

Among the survey respondents, bivariate analyses were conducted to examine the relation of measures of utilization of medical treatments for ED with demographic, medical, sexual, and psychological characteristics. These analyses included independent sample t tests on group means, analyses of variance, and chi-square contingency table analyses when appropriate.

Logistic regression was used to develop models of the factors that were associated significantly with outcome measures, including whether or not a man tried a treatment for ED, improvement reported with treatment, and continued use of treatment. A sequential, backward selection approach to model development was adopted within each subset. Demographic variables were added first (age, years married, education, ethnicity, marital status, age difference between man and his partner, religion, and religious observance). The variables that were significant in the multivariate analysis at P < 0.01 were retained in the model. The next subset included health-related factors (SF-36 Physical Composite Score [PCS] and SF-36 Mental Composite Score [MCS]), clinical disease stage, years since treatment, treatment modality, neoadjuvant hormone therapy, current hormone therapy, PCI urinary and bowel symptom scores, and current evidence of biochemical failure (elevated PSA level). Again, factors that were significant at P < 0.01 were retained in the model, and sexual factors were added subsequently, including prospective physician report of pretreatment erectile function, the priority a man put on preserving sexual function in choosing his treatment for prostate carcinoma, sexual orientation, lifetime number of sexual partners, whether or not he had a sexual partner in the past year, duration of current sexual relationship, a mate who was free of sexual dysfunction or problems, and overall score on the SSSS-M. When appropriate, factors that were related to the success of therapies for ED or numbers of therapies tried were added last. Appropriate diagnostics (e.g., standardized β values for degrees of freedom) were examined to explore the presence of consistently influential observations. The diagnostic analyses did not suggest the exclusion of any cases. Final models were constructed using logistic regression. All significant factors from previous subset analyses were included in the final analysis. Model parameter estimates were examined, and corresponding tests are reported.

RESULTS

Sample Characteristics

The return rate for questionnaires was 49%, excluding 45 men who were deceased or had cognitive disabilities that prevented them from completing the questionnaire and 44 men with invalid mailing addresses, yielding a sample of 1236 men. The mean age ± standard deviation (SD) of the men in our sample was 68.6 ± 7.5 years (range, 42–88 years), and the mean time since treatment ± SD was 4.3 ± 2.9 years. Our sample was comprised of well educated men: Only 8% of men less than a high school education, and 23% of men had a postgraduate degree. white men comprised 90% of the sample, with 10% of respondents African-American men, and < 1% of men with other ethnicities. Eight percent of men reported taking antiandrogen therapy for prostate carcinoma at the time of the survey, and 27% of men had used neoadjuvant hormone therapy in the past. Most men (86%) were married, and another 6% of men were in a committed relationship. Seventy-three percent of men had been in a relationship with their current sexual partner for > 10 years.

Survey Respondents versus Nonrespondents

Men who returned their questionnaires were compared with men who did not return their questionnaires on a number of demographic and medical variables from the registry data.31 African-American men were significantly less likely than white men to participate in the survey (response rate: 30% compared with 52% for white men). Men who returned their questionnaires were slightly younger, more likely to have undergone surgical treatment, and were more likely to have been potent before they received treatment for prostate carcinoma, as determined by chart review. These three group differences suggest that men who responded may have been the men who were most interested in staying sexually active.

Defining the Subsample of Sexually Dysfunctional Men

Eighty-five percent of respondents reported that they had ED within the past 6 months.31 According to the prostate registry, 36% of men had ED before they were treated for prostate carcinoma. We used responses to several survey questions to exclude 48 men who reported that they were able to achieve satisfying erections without the aid of medical treatments before they were diagnosed with prostate carcinoma and at the time of our survey, i.e., men who had maintained normal erectile function without experiencing a significant period of temporary ED after they were treated for prostate carcinoma. Our resulting subsample included 1188 sexually dysfunctional men.

Success of Medical Treatments for Men with ED

Of the men who had a sexual problem, 59% reported trying at least 1 medical or psychological treatment for ED. These 676 men tried a mean ± SD of 1.95 ± 1.21 treatments. The median number of treatments was also two. Table 1 summarizes the types of treatments men employed, how helpful men found them, and how likely men were to still be using them at the time of the survey. The final column in Table 1 shows how many men said they would like to try a treatment in the future.

Table 1. Types of Treatment Options Tried for Erectile Dysfunction, Success Rates, Treatment Adherence, and Desire to Try in the Future (n = 1188 Men with Erectile Dysfunction)
Treatment optionMen who tried the optionMen who tried the option (%)aPercentage of the sample who would like to try the option in the future
No.%Somewhat improvedGreatly improvedStill using treatment
  • a

    Percentages may be based on a somewhat lower number of men in some instances because of missing data.

Sexual counseling145142972917
Sildenafil5495233163918
Testosterone replacement48526123115
Other oral medication21244114727
Penile injections179184329349
Intraurethral prostaglandin103104162115
Vacuum device1971944194110
Penile prosthesis1623844815
Herbs or vitamins6063404240

In general, men who keep on using a treatment appear to be those who find that it greatly improves sexual function along with some percentage of men who find it somewhat helpful. Only the most invasive treatments (specifically, penile injection therapy and penile prosthesis surgery) achieved reasonable success rates (i.e., they greatly improved sex for > 25% of men who tried them). However, men remain interested in trying the least invasive treatments, such as sildenafil, new oral medications for ED, or herbs and vitamins.

One hundred eighty-nine men (16%) indicated that they were reporting on sexual activity while using a medical treatment. We were able to calculate the erectile function (EF) subscale score of the IIEF for 172 of these 189 men. To identify men who had functional erections at the time of our survey, we used the criterion a score of ≥ 22 on the EF subscale of the IIEF.36 This score range has been validated and includes men with minimal to mild erection problems as well as men with completely normal erectile function. Table 2 summarizes the percentage of men who used a medical therapy for ED and achieved functional erections (i.e., EF subscale score ≤ 22). Overall, 52% of men who used a medical treatment for ED had functional erections compared with only 12% of men who did not employ a medical treatment (P < 0.0001).

Table 2. Rate of Functional Erections in 172 Men Who Used Medical Treatments for Erectile Dysfunction
Treatment optionNo. of men using optionMen with EF scores ≥ 22 (%)a
  • EF: erectile function.

  • a

    An EF score ≥ 22 on the Erectile Function subscale of the International Index of Erectile Function represents men who report mild erection problems or normal erections.

Sildenafil9953
Other oral medication475
Penile injections3269
Vacuum device1833
Penile prosthesis1100
Intraurethral prostaglandin333
Other1527

The Success of Sildenafil and the Type of Treatment for Men with Prostate Carcinoma

Because sildenafil was far the most popular treatment for ED by far, Table 3 presents data for the 549 men who tried sildenafil, comparing the rates of improvement and continued use of this medication for men who had received different types of therapy for prostate carcinoma. Overall, 49% of men who tried sildenafil reported that it improved their sex life at least to some extent, and 39% of men still were using it at the time of the survey. Sildenafil was more successful after treatments for prostate carcinoma that were less likely to damage the erection reflex.31

Table 3. Success of Sildenafil Citrate and Type of Treatment for Prostate Carcinomaa
Treatment for prostate carcinomaNo.Men who reported at least some improvement (%)Men who still were using sildenafil at the time of the survey (%)
  • 3D: three-dimensional.

  • a

    Because there were some missing data for 51 patients, only 549 men were included here.

Bilateral nerve-sparing prostatectomy1615547
Unilateral nerve-sparing prostatectomy503832
Prostatectomy, no nerve-sparing1132715
Brachytherapy546959
3D-conformal or intensity modulated925848
Standard external radiation therapy285732

Which Men Try a Medical Treatment for ED?

Six hundred twenty-three men (59%) had tried at least 1 treatment for ED. Tables 4 and 5 show that the constructed logistic regression model explained 24% of the variance in who tried a treatment for ED. The factors that had significant explanatory power (P < 0.01) in the model were having a committed relationship (61% of men who were married or in a committed relationship tried a treatment compared with 43% of men without a relationship), having a newer relationship (mean ± SD: 33.01 ± 16.10 years for men who tried a treatment for ED compared with 39.34 ± 16.09 years for men who did not try a treatment for ED), the modality of treatment for prostate carcinoma (treatments for ED were tried by 79% of men who underwent bilateral nerve-sparing prostatectomy, 66% of men who underwent unilateral nerve-sparing prostatectomy, 59% of men who did not undergo nerve-sparing surgery, 50% of men who received brachytherapy, 52% of men who received three-dimensional (3D) conformal or intensity-modulated radiotherapy, and 45% of men who received standard radiotherapy), putting a higher priority on preserving sexual function in choosing a treatment for prostate carcinoma (treatments were tried by 73% of men who put a major priority on sex compared with 65% of men who put a minor priority on sex and 50% of men for whom sex did not influence the treatment choice), and having had at least 1 sexual partner in the past year (73% of men with a sexual partner tried a treatment for ED compared with 43% of men without a partner).

Table 4. Logistic Regression Model of Treatment Use among Men with Erectile Dysfunction: Type III Analysis of Effects (n = 1038 men)a
EffectType III analysis of effects
DFWald chi-squarebP value
  • DF: degrees of freedom; CA: carcinoma; TX: therapy; ED: erectile dysfunction.

  • a

    Observations were missing for 150 men who were not included in the model.

  • b

    Correlation coefficient (R2) = 0.18; maximum rescaled R2 = 0.24.

Age13.840.0500
Yrs in relationship110.890.0010
Married vs. partnered vs. single212.480.0020
CA TX modality535.85<0.0001
Priority placed on ED in choosing CA TX229.96<0.0001
Had a sexual partner in past year139.19<0.0001
Table 5. Logistic Regression Model of Treatment Use among Men with Erectile Dysfunction: Odds Ratio Estimates (n = 1038 men)a
EffectOdds ratio estimates
Point estimate95% Wald confidence limits
  • NS: nerve-sparing; RP: radical prostatectomy; 3D: three-dimensional conformal radiotherapy; IM: intensity-modulated radiation therapy; XRT: radiotherapy; CA: carcinoma; TX: therapy.

  • a

    Observations were missing for 150 men who were not included in the model.

Age0.980.96–1.00
Yrs in relationship0.980.97–0.99
Married vs. single without partner2.951.59–5.47
Unmarried with vs. without partner3.111.33–7.24
Bilateral NS RP vs. no NS RP1.490.95–2.33
Unilateral NS RP vs. no NS RP1.140.66–1.98
3D or IM XRT vs. standard XRT0.840.52–1.37
Brachytherapy vs. standard XRT0.570.33–1.00
ED major vs. no influence on CA TX2.761.89–4.05
ED minor vs. no influence on CA TX1.731.25–2.40
Had ≥ 1 sex partner in past year vs. 02.481.86–3.29

Although the association was not significant in the final model, bivariate analyses revealed a number of other factors that were associated significantly (P < 0.01) with having tried a treatment for ED. These included following factors: Men who tried a treatment were significantly younger, had younger partners with a significantly larger older male/younger female age gap, perceived their physical health more positively, were less likely to be in biochemical failure or to be on current antiandrogen therapy, had more lifetime sexual partners, had good erections before treatment for prostate carcinoma, and had a more positive SSSS-M score. Among men who had a sexual partner in the past year, the men with partners who were free of sexual problems were more likely to try a treatment. It should be noted however, that some men who were married or were in a committed relationship reported that they did not have a sexual partner in the past year. Presumably, this reflects a lack of sexual activity for the couple.

Which Men Rate Treatments for ED as Successful?

A conservative measure of the overall success of medical treatments for ED was whether a man rated at least one treatment as having improved his sex life at least somewhat. Thirty-eight percent of the entire sample of men with sexual dysfunction met this criterion. To create a model of the factors that were associated with improved sexual function when using a treatment for ED, we included only the men who reported that they tried at least one treatment. Within this group, 64% of men rated a treatment as at least somewhat helpful. The modeling procedure was identical to the procedure described above, except that we added another factor after the final set: the number of ED treatment modalities tried among the nine treatment modalities listed.

In bivariate analyses, factors that reached significance at the P < 0.01 level but did not attain significance in the final model included the following: Men who rated a treatment as helpful rated their physical health more positively (SF-36 PCS); they were more likely to have had good erections before they were treated for prostate carcinoma;, and they were more likely to have undergone bilateral, nerve-sparing, radical prostatectomy as their treatment (74% of these men said that a treatment for ED was helpful compared with 65% of men who received brachytherapy or newer methods of external beam radiotherapy, 62% of men who received standard radiotherapy or underwent unilateral nerve-sparing surgery, and 53% of men who underwent prostatectomy without nerve sparing).

The logistic regression model presented in Tables 6 and 7 explains 18% of the variance in the success of treatments for men with ED. Men who tried a treatment for ED and experienced improved sexual function were younger (mean age ± SD: 66.13 ± 7.66 years compared with 68.62 ± 7.03 years for men without improvement from treatment), were less likely to have had neoadjuvant hormone therapy (54% of men who had past hormone therapy reported improvement compared with 68% of men who had no hormone therapy), were more likely to have had a sexual partner in the past year (71% of men with a partner tried a treatment compared with 49% of men without a partner), and had tried a greater number of treatments for ED (mean ± SD: 1.55 ± 0.91 treatments tried by men who reported no improvement compared with 2.18 ± 1.29 treatments tried by men who reported an improvement).

Table 6. Logistic Regression Model Describing Factors Related to Reported Improvements with Treatment for Erectile Dysfunction: Type III Analysis of Effects (n = 654 men)a
EffectType III analysis of effects
DFWald chi-squarebP value
  • DF: degrees of freedom; ED: erectile dysfunction.

  • a

    Twenty-two observations were deleted due to missing values.

  • b

    Correlation coefficient (R2) = 0.13; maximum rescaled R2 = 0.18.

Age17.840.0051
Neoadjuvant hormonal therapy18.330.0039
Had sexual partner in past year122.16<0.0001
No. of treatments for ED tried134.35<0.0001
Table 7. Logistic Regression Model Describing Factors Related to Reported Improvements with Treatment for Erectile Dysfunction: Odds Ratio Estimates (n = 654 men)a
EffectOdds ratio estimates
Point estimate95% Wald confidence limits
  • ED: erectile dysfunction.

  • a

    Twenty-two observations were deleted due to missing values.

Age0.970.94–0.99
Neoadjuvant hormonal therapy0.560.04–0.83
Had sexual partner in past year2.391.66–3.43
No. of treatments for ED tried1.711.43–2.04

Which Men Continue Using a Treatment for ED?

A measure of adherence to medical treatment was whether a man still was using at least one treatment for ED. At the time of the survey, a medical treatment for ED was being used by 30% of the entire sample of men with ED and by 51% of the men who had tried at least 1 treatment. A logistic regression model was constructed in a manner similar to that used to construct the model for trying a treatment for ED, with the exception that an additional factor was included as a final step: whether or not a treatment had improved sexual function.

Tables 8 and 9 present the model, which explains 44% of the variance in adherence to treatment. Factors that were significant in the final model included not having failed biochemically (54% of men with normal PSA levels still were using a treatment compared with 32% of men with abnormal PSA levels), having at least 1 sexual partner during the past year (59% of men with a partner still were using a treatment compared with 35% of men without a partner), and having experienced improved sexual function from a treatment (72% of men who rated a treatment as helpful were adherent compared with. 12% of men who did not rate a treatment as helpful). Age was retained as a factor in the final model. Although age was not significant after adding other variables, bivariate analysis indicated that younger men were more likely to adhere to treatment (mean age ± SD: 65.72 ± 7.33 years for adherent men compared with 68.28 ± 7.51 years for men who were no longer using a treatment; P < 0.01).

Table 8. Logistic Regression Model Describing Factors Related to the Continued Use of Treatments for Erectile Dysfunction: Type III Analysis of Effects (n = 662 men)a
EffectType III analysis of effects
DFWald chi-squarebP value
  • PSA: prostate specific antigen; ED: erectile dysfunction.

  • a

    Twenty-six observations were deleted due to missing values.

  • b

    Correlation coefficient (R2) = 0.33; maximum rescaled R2 = 0.44.

Age11.770.1830
Biochemical failure (abnormal PSA)18.300.0040
Had sexual partner in past year18.230.0041
Experienced improved ED from treatment1153.36<0.0001
Table 9. Logistic Regression Model Describing Factors Related to the Continued Use of Treatments for Erectile Dysfunction: Odds Ratio Estimates (n = 662 men)a
EffectOdds ratio estimates
Point estimate95% Wald confidence limits
  • ED: erectile dysfunction.

  • a

    Twenty-six observations were deleted due to missing values.

Age0.980.96–1.01
Neoadjuvant hormonal therapy0.430.24–0.76
Had sexual partner in past year1.861.22–2.84
Treatment improved ED17.5611.16–27.64

Other factors that were related significantly (P < 0.01) to treatment adherence in bivariate analyses, but not in the final model, included perceiving oneself as in better physical health, prostate carcinoma treatment modality (64% of men who underwent bilateral nerve-sparing surgery still were using a treatment as well as 55% of men after receiving brachytherapy, 50% of men after receiving 3D-conformal or intensity-modulated radiotherapy, 43% of men after standard radiotherapy, 42% of men after undergoing prostatectomy without nerve sparing, and 41% of men after undergoing unilateral nerve-sparing surgery), not being on current antiandrogen therapy, having had good erections before treatment for prostate carcinoma, and putting a high priority on choosing a treatment for prostate carcinoma that may spare sexual function.

DISCUSSION

It is gratifying that 59% of sexually dysfunctional men tried a treatment for ED after prostate carcinoma, although even higher rates would be optimal. Unfortunately, all current treatments, except for implantation of a penile prosthesis, have drop-out rates that exceed 50% among this group of men, so that only 30% of men are using a therapy to improve their erections at an average of 4.5 years of follow-up. Treatment effectiveness is a major factor in continuing to use a particular modality. Paradoxically, men are much more likely to try noninvasive treatments, such as an oral medication, to improve erections; whereas the most successful treatments remain the most invasive: penile prosthesis surgery or penile injection therapy.

Although sildenafil was the most popular treatment option by far, only 39% of men who tried sildenafil continued to use it. According to a validated measure of erectile function, a mere half of this continuing user group achieved erections that were near normal in firmness and reliability. Men who received treatments for prostate carcinoma with less severe impact on erectile function, including nerve-sparing radical prostatectomy or newer types of radiation therapy, had better success with sildenafil, as the literature suggests.3–6, 8–13 We did not collect detailed information on dosage, number of trials of the medication, or timing of use after surgery or radiation; however, such factors obviously can affect the likelihood that sildenafil will improve erections.

Men who tried two or more ED treatment options were more likely to find one that worked. Their persistence may reflect the strength of their motivation to stay active sexually, because men who put a high priority on finding a treatment for prostate carcinoma designed to spare erectile function also were more likely to try a treatment for ED when their erections did not recover. Although the correlations were not as strong, younger age, better physical health, and having had good sexual function before the diagnosis of prostate carcinoma also contributed to the motivation to resolve ED. In a similar vein, men who had a greater lifetime number of sexual partners and who viewed their sexuality as a positive aspect of their selfhood (SSSS-M score) also were more likely to try to remediate ED.

The type of treatment for prostate carcinoma was another factor in men's willingness to try a treatment option to resolve ED. Men who underwent bilateral nerve-sparing surgery were the most likely to try a treatment for ED: They were 1.6 times more likely to try a therapy for ED compared with men who received brachytherapy. In general, men who underwent surgery were more likely to try a treatment for ED, perhaps because men who put a high priority on staying functional sexually tend to choose radical prostatectomy. Men who underwent treatments like bilateral nerve-sparing surgery or brachytherapy, which are somewhat more likely to leave some tumescence intact,31 were able to use sildenafil more successfully, and the success of therapies for ED was the strongest correlate of their continued use. Rates of adherence to medical therapies for ED after prostate carcinoma were strikingly similar to follow-up data on the long-term outcome of treatment by ED clinics.24–26

The negative impact of hormone therapy on the successful treatment of patients with ED also is clear. The profound disruption of sexual function in men who are on antiandrogen therapy has been well documented.37 Men who were on current antiandrogen therapy or were in biochemical failure were less likely to try a treatment for ED. These relations did not maintain significance in the multivariate model, perhaps because only 17% of men had abnormal PSA levels, and only 8% of men currently were using hormone therapy. Treatments for ED worked less well in men who had been given neoadjuvant antiandrogen therapy. This finding reinforces several recent case series that reported the long-term, negative effects of neoadjuvant hormones on sexual function.31, 38–41 Although current antiandrogen therapy was not associated with the efficacy of medical treatment for ED, few men on hormone therapy had attempted to treat their sexual dysfunction. When men did try a treatment for ED, men who currently were in biochemical failure or on hormone therapy were more likely to discontinue it. The addition of antiandrogen therapy probably interfered with the efficacy of treatments for ED.

It is of some concern that 48 men had tried replacement testosterone, and 14 men still were using it at the time of the survey. Some of these men may have used testosterone before their diagnosis of prostate carcinoma, and others may have misinterpreted the question. Our questionnaire asterisked this item and added a footnote directly under the relevant section, stating that men with a diagnosis of prostate carcinoma should not use testosterone replacement.

Relationship factors are important in explaining successful use of a medical treatment. Men in a relationship are more likely to try a treatment for ED, particularly if the sexual partner has good sexual function. The survey also confirmed our clinical observation that men in newer relationships, and especially those with a partner who is significantly younger, are more likely to be distressed about sexual dysfunction after prostate carcinoma.

Although it may be difficult to change a man's basic motivation to stay active sexually, our findings do suggest some interventions that have the potential to enhance men's success in using treatments for ED. A major goal of counseling should be to create more realistic expectations about these options in men and their partners. Advertising and news reports on new treatments for ED often give couples unrealistic expectations, presenting the option as a cure that will restore men to the sexual prowess of their youth with minimal side effects or problems. In fact, all treatments require some accommodation in love-making, ranging from taking sildenafil a long enough time before attempting intercourse, avoiding the use of alcohol or heavy meals on these occasions, to the complex skills of learning to inject a medication into the corpora cavernosa before starting foreplay, or interrupting caressing to use a vacuum device. Such changes in routine require open sexual communication and a willingness to give up spontaneity. These skills and attitudes can be taught.

Although the current survey demonstrated that the partner's ability to enjoy sex has a major influence on men's ultimate sexual satisfaction and function,31 most ED clinics make little effort to include the partner in treatment planning. Many men regard ED as their individual problem; however, sex takes place in a relationship. Not only do many couples have inadequate skills to change their love-making to incorporate a medical treatment for ED, but postmenopausal women often have sexual problems themselves. One of the most common is that the woman's desire for sex has been damaged by the stress of the man's prostate carcinoma and alienation caused by failed efforts to cope with ED.31

One solution to these problems may be to incorporate sexual counseling routinely into follow-up care for survivors of prostate carcinoma. Couples in a committed relationship may be helped to make a mutual decision about whether to pursue a treatment modality and about the option that is most acceptable. Sex therapy offers techniques with empirical success in reducing performance anxiety and enhancing skills at sexual communication and stimulation. Such techniques may help with desire and orgasm problems, even if they cannot change organic ED. Sexual counseling may be accomplished in several sessions administered by a trained oncology nurse or social worker.42, 43 If such programs were offered in oncology care settings, they could be viewed as complementary therapies rather than bearing the stigma of referring patients to an outside mental health professional. We currently are evaluating such a counseling program. Unfortunately, third-party insurers and managed-care plans often will not reimburse for sexual counseling, leaving men and their partners waiting for approval of the next miracle drug or device for men with ED or for the next erection-sparing treatment for men with prostate carcinoma.

Ancillary