Introduction. University, Beachwood, OH, USA; 3 Pfizer Inc, New York, NY, USA ABSTRACT

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1 Blackwell Science, LtdOxford, UKVHEValue in Health ISPOR /05? Original ArticleEDITS/SEAR AssociationCappelleri et al. Volume 8 Supplement VALUE IN HEALTH Association between the Erectile Dysfunction Inventory of Treatment Satisfaction and the Self-Esteem and Questionnaire Following Treatment with Sildenafil Citrate for Men with Erectile Dysfunction Joseph C. Cappelleri, PhD, 1 Stanley E. Althof, PhD, 2 Richard L. Siegel, MD, 3 Vera J. Stecher, PhD, 3 Li-Jung Tseng, PhD, 3 Sandeep Duttagupta, PhD 3 1 Pfizer Inc, Global Research & Development, Groton, CT, USA; 2 Center for Marital and Sexual Health, Case Western Reserve University, Beachwood, OH, USA; 3 Pfizer Inc, New York, NY, USA ABSTRACT Objectives: Research is lacking on the correlation between treatment satisfaction and confidence, selfesteem, and relationships for men receiving treatment for erectile dysfunction (ED). We sought to correlate scores between the validated Erectile Dysfunction Inventory of Treatment Satisfaction (EDITS) index and the validated Self-Esteem And (SEAR) questionnaire following treatment with sildenafil citrate (VIAGRA). Methods: This study was based on an open-label, flexible-dose trial of 93 sildenafil-naive patients with ED. Pearson correlation coefficients between EDITS index and SEAR questionnaire scores, each of which can range from 0 to 100 (most favorable), were calculated at end of treatment (EOT). An analysis of covariance model was applied to associate changes from baseline to EOT in SEAR scores with EDITS score at EOT, controlling for baseline SEAR score. Results: Significant and sizable Pearson s correlations between SEAR and EDITS scores (P ; range: ) were observed. A 10-point higher EDITS scores at EOT corresponded to a significant and tangible average improvement in SEAR scores from baseline to EOT (P ; range: ). Average SEAR scores at EOT were markedly different between patients with greater treatment satisfaction at EOT (EDITS score median EDITS score of 88.6; n = 50) and those with lesser treatment satisfaction at EOT (EDITS score <88.6; n = 43). Conclusions: The data add to the validity of the SEAR questionnaire, suggest a tangible relationship between treatment satisfaction and psychosocial benefit among men with ED treated with sildenafil, and highlight the importance of assessing the psychosocial impact of ED in men undergoing treatment. Keywords: confidence, erectile dysfunction, psychometrics, quality of life, relationships, self-esteem, sildenafil citrate, Viagra. Introduction Address correspondence to: Joseph C. Cappelleri, Pfizer Inc, Global Research & Development, MS , Eastern Point Road, Groton, CT , USA. joseph.c.cappelleri@pfizer.com doi: /j x Erectile dysfunction (ED) is defined as the inability to achieve or maintain an erection sufficient for sexual intercourse [1], and is a prevalent condition affecting as many as 50% of men over the age of 40 years [2]. The incidence of ED increases substantially with age, approximately doubling with each decade of life after 50 years [2]. ED is a common complication of spinal cord injury and prostate surgery [3,4]; is often a comorbid condition of diabetes, depression, and other diseases [5 9]; and may be a symptom of underlying, chronic systemic vascular disease [10 12]. Nevertheless, ED is often undertreated [13]. Moreover, men are often reluctant or embarrassed to discuss sexual issues [14], making diagnosis and treatment a challenge for health-care providers. Sexual and erectile function are considered important components of men s overall health [15]. The psychosocial impact of ED can lead to depression, loss of self-esteem, and relationship and marital difficulties [16]. A review of clinical trials showed that successful ED treatment was associated with improved sexual, relational, and emotional aspects of the lives of patients with ED, regardless ISPOR /05/S54 S54 S60 S54

2 EDITS/SEAR Association of the specific therapy used [16]. Three of these studies assessed the impact of sildenafil in a doubleblind placebo-controlled setting [3,17,18]. Sildenafil was significantly associated with clear improvements in several components of sexual function (ability to achieve and maintain an erection, sexual satisfaction), mental health (well-being, depression, anxiety), and quality of life after successful treatment of ED [18,19]. Thus, assessing the psychosocial impact of ED is relevant toward understanding and measuring sexual, relationship, and emotional s of treatment outcomes of interest to patients. More recently, three independent clinical trials with sildenafil one an open-label trial [20] and two double-blind placebo-controlled studies [21,22] have demonstrated major psychosocial gains in self-esteem, confidence, and relationships as measured by the Self-Esteem and (SEAR) questionnaire, an ED-specific instrument that has undergone rigorous development and validation [20,23]. Focus groups of men with ED, their female partners, and physicians, along with the clinical literature, have provided testimony that improved self-esteem, confidence, and relationships add value to health in men with ED [23]. The three studies [20 22] also demonstrated uniformly large gains in erectile and sexual functioning. For example, in the open-label trial [20], mean scores for the erectile function of the International Index of Erectile Function (IIEF) (range: 1 [lowest] to 30 [highest]) increased significantly from 15.5 (SD 6.4) at baseline to 25.6 (SD 6.8) at end of treatment (EOT) (P = ); the remaining four s on the IIEF also showed considerable improvement. Changes in Erectile Function score correlated moderately with changes in SEAR and scores (Sexual, r = 0.69; Confidence, r = 0.48; Self-Esteem, r = 0.47;, r = 0.35; P 0.001). The Erectile Dysfunction Inventory of Treatment Satisfaction (EDITS), another well-validated EDspecific instrument, was developed to assess satisfaction with ED therapies and to explore the impact of patient and partner satisfaction on treatment continuation [24]. EDITS has been used to evaluate patients satisfaction with therapies such as sildenafil, apomorphine, intracavernosal injections, and penile prosthesis [25 27] for the treatment of ED of varied etiologies, including Peyronie s disease [28] and following therapy for prostate cancer [29]. To fully assess how ED therapy affects a patient s condition, we need to consider different questionnaires each intended to measure a different aspect of S55 how ED therapy affects a patient s profile. Efficacy assessments of ED therapies like the IIEF primarily focus on the patient s erection and associated sexual functioning. Treatment satisfaction measures like the EDITS focus on treatment satisfaction, a characteristic feature of ED therapy. Measures like the SEAR questionnaire focus on the broader psychosocial impact of the condition. Research is lacking, however, on the association between treatment satisfaction and improvements in psychosocial factors following a beneficial intervention for ED. Treatment satisfaction is critical in helping to prevent therapy discontinuation for patients with ED [30,31]. A tangible association between treatment satisfaction and psychosocial factors like self-esteem, confidence, and relationships may suggest that these factors are also relevant for treatment adherence. We therefore investigated the relationship between the EDITS index and the SEAR questionnaire in patients treated with a beneficial intervention for ED. Methods Study Design The current study was part of a larger investigation to assess the responsiveness of change scores on the SEAR questionnaire and especially its self-esteem in a multicenter, open-label, flexible-dose ( mg) clinical trial in sildenafil-naïve men with ED [20]. Patients were 18 years or older, in a stable relationship with a single partner, and had clinically documented ED. Following a 2-week screening phase, patients received sildenafil (initial dose 50 mg, adjustable to 100 mg or 25 mg based on efficacy and tolerability) to be taken as needed for 10 weeks. Patients were excluded if they had sitting hypotension (blood pressure <90/50 mm Hg) or severe hypertension (blood pressure >170/ 110 mm Hg) or significant cardiovascular disease. Patients were excluded if they were taking nitrates or nitric oxide donors or CYP3A4 inhibitors, were previously treated with sildenafil, or were currently taking any other treatment for ED. The study was approved by an Institutional Review Board, was conducted in accordance with Good Clinical Practice requirements, and in full compliance with the most recent amendments of the World Medical Assembly Declaration of Helsinki. Efficacy Measures In this report we focused on the association between treatment satisfaction as measured by the EDITS index and psychosocial factors as measured

3 S56 Cappelleri et al. Table 1 The EDITS index (patient version) 1., how satisfied are you with this treatment? 2. During the past 4 weeks, to what degree has the treatment met your expectations? 3. How likely are you to continue using this treatment? 4. During the past 4 weeks, how easy was it for you to use this treatment? 5. During the past 4 weeks, how satisfied have you been with how quickly the treatment works? 6. During the past 4 weeks, how satisfied have you been with how long the treatment lasts? 7. How confident has this treatment made you feel about your ability to engage in sexual activity? 8., how satisfied do you believe your partner is with the effects of this treatment? 9. How does your partner feel about your continuing to use this treatment? 10. How natural did the process of achieving an erection feel when you used this treatment during the past 4 weeks? 11. Compared to before you had an erection problem how would you rate the naturalness of your erection when you used this treatment during the past 4 weeks in terms of hardness? Response options are specific for each question: 0 = Very dissatisfied/did not meet expectations/very unlikely to continue/very difficult to use, etc. 4 = Very satisfied/completely met expectations/very likely to continue/very easy to use, etc. The EDITS index is calculated by multiplying the mean score of all 11 items by 25, which yields a total score ranging from 0 (lowest satisfaction) to 100 (highest satisfaction). by the SEAR questionnaire. The EDITS (patient version) consists of 11 items, scored from 0 (low satisfaction) to 4 (high satisfaction), and an EDITS index score is calculated by multiplying the mean score of all 11 items by 25, which yields a total score ranging from 0 (lowest satisfaction) to 100 (highest satisfaction) (Table 1). The EDITS index was administered only at EOT. We restricted attention to EDITS as reported by the patient and did not consider the optional partner EDITS responses because partner responses were too limited for meaningful analysis. Table 2 The SEAR questionnaire 1. Sexual During the past 4 weeks: 1). I felt relaxed about initiating sex with my partner. 2). I felt confident that during sex my erection would last long enough. 3). I was satisfied with my sexual performance. 4). I felt that sex could be spontaneous. 5). I was likely to initiate sex. 6). I felt confident about performing sexually. 7). I was satisfied with our sex life. 8). My partner was unhappy with the quality of our sexual relations. 2. Confidence 2a. Self-Esteem 9). I had good self-esteem. 10). I felt like a whole man. 11). I was inclined to feel that I am a failure. 12). I felt confident. 2b. 13). My partner was satisfied with our relationship in general 14). I was satisfied with our relationship in general. Response options: 1 = Almost never/never 2 = A few times (much less than half the time) 3 = Sometimes (about half the time) 4 = Most times (much more than half the time) 5 = Almost always/always Note: Questions 8 and 11 are reverse scored and all scores are transformed onto a scale so that a higher score indicates a more favorable response to treatment for all 14 items. The SEAR questionnaire is composed of two s, Sexual (items 1 8) and Confidence (items 9 14); the Confidence is decomposed into two s, Self-Esteem (items 9 12) and (items 13 and 14) (Table 2) [20,23]. Scores are determined by summing their respective items and transforming them onto a scale; higher scores indicate a more favorable response. The SEAR questionnaire was completed at baseline and EOT. Statistical Analysis Pearson correlation coefficients between scores on the EDITS index and the SEAR questionnaire were computed at EOT. An analysis of covariance model was applied to associate changes (baseline to EOT) in SEAR score with EDITS score at EOT, controlling for baseline SEAR score. Descriptive profiles with mean and 95% confidence intervals on the SEAR questionnaire at EOT were partitioned by the median EDITS score at EOT. All analyses were performed with SAS software (SAS Institute Inc. 1999, Version 8, Cary, NC). Results Baseline Characteristics A total of 101 patients enrolled in the study (Table 3). Comorbid medical conditions included borderline or mild hypertension (48%), hypercholesterolemia (23%), unspecified hyperlipidemia (16%), diabetes (14%), benign prostatic hyperplasia (13%), esophagitis (12%), depression (9%), and ischemic heart disease (8%). Of these patients, 93 (92.1%) had taken at least one sildenafil dose and had at least one efficacy evaluation (EOT or time of discontinuation) and were

4 EDITS/SEAR Association Table 3 Patient characteristics at baseline (n = 101) Age (year) Mean ± SD (range) 55 ± 12 (27 81) Race, n (%) White 66 (65) African American 26 (26) Asian 1 (1) Other 8 (8) Duration of ED (year) Mean ± SD (range) 4.6 ± 7.5 ( ) Primary etiology of ED, n (%) Psychogenic 26 (26) Organic 48 (48) Mixed 26 (26) Unknown 1 (1) SEAR component (n = 93), mean ± SD 1. Sexual 42.1 ± Confidence 55.0 ± a. Self-Esteem 51.6 ± b ± (total) score 47.6 ± 21.6 included in the intent-to-treat analysis of the SEAR questionnaire. Association between EDITS Index and SEAR Questionnaire EDITS index scores at EOT showed moderate-tohigh correlations with SEAR questionnaire scores at EOT, ranging from 0.49 with the to 0.84 with the Sexual of the SEAR questionnaire (Table 4); therefore, all correlations were tangible and, in addition, statistically significant (P ). A 10-point higher EDITS score at EOT (e.g., a patient with a score of 70 compared with another patient with a score of 60) corresponded to a statistically significant (P ) average improvement in SEAR scores from baseline to EOT, ranging S57 Table 4 Descriptive statistics and correlations on SEAR questionnaire and EDITS index at end of treatment (n = 93) SEAR components SEAR score (Mean ± SD) Correlation with EDITS* 1. Sexual (77.8 ± 21.1) Confidence (80.7 ± 21.2) a. Self-Esteem (81.0 ± 22.4) b. (81.0 ± 24.4) score (78.9 ± 20.3) 0.79 *P EDITS score: mean ± SD = 82.6 ± from 6.6 with the to 8.7 with the Sexual (Fig. 1). Variation in EDITS scores, along with variation in baseline SEAR scores, accounted for a substantial proportion of variation in changes in SEAR scores (Sexual, r 2 = 0.78; Confidence, r 2 = 0.70; Self-Esteem, r 2 = 0.70;, r 2 = 0.63;, r 2 = 0.76). The median EDITS score was Descriptive profiles of SEAR scores were markedly different between patients with greater treatment satisfaction (i.e., greater than or equal to the median EDITS score of 88.6; n = 50) and those with lesser treatment satisfaction (less than the median EDITS score of 88.6; n = 43; Fig. 2). Similar results would be obtained if the mean EDITS score of 82.6 (SD 18.9) was used instead of the median EDITS score as the cutoff score of central tendency. Inferential results with an analysis of covariance model, adjusting for corresponding baseline SEAR score, confirmed similar differences in mean SEAR scores between the two groups of EDITS scores split at the median EDITS score (P ). Figure 1 between EDITS index at end of treatment and changes on the SEAR questionnaire. Higher scores on the EDITS questionnaire, indicating higher levels of treatment satisfaction with sildenafil, were associated with improvements on all SEAR components. Data are the mean improvement (from baseline to end of treatment) in SEAR score for a 10-point higher EDITS score at end of treatment. Error bar represents 95% confidence interval (CI), n = 93. Mean improvement in SEAR scores for 10-point higher EDITS score (95% CI) Sexual Confidence Self- Esteem SEAR questionnaire score

5 S58 Cappelleri et al Mean SEAR scores (95% CI) Sexual Confidence Self- Esteem SEAR questionnaire score Figure 2 Mean SEAR scores at end of treatment, partitioned by median EDITS score at end of treatment. The median score was Compared with patients who reported lower levels of treatment satisfaction (EDITS score < median EDITS score of 88.6; n = 43), patients who reported greater treatment satisfaction (EDITS score 88.6; n = 50) reported higher scores on all facets of the SEAR questionnaire. Error bar represents 95% confidence interval (CI), n = 93. ( ) Mean SEAR score among patients who had an EDITS score equal to or greater than the median score of 88.6 (n = 50); ( ) mean SEAR score among patients who had an EDITS score less than the median score of 88.6 (n = 43). Discussion Erectile dysfunction can diminish self-esteem, confidence, and relationships [20]. The inability to perform sexually can have a significant negative impact on overall health and aspects of quality of life [32]. The World Health Organization includes emotional and psychological well-being in its definition of health [15], and normal sexual function is an important component of men s psychological wellbeing and functioning. Confirmatory evidence indicates that successful treatment of ED improves psychological and interpersonal relationships [33] as well as quality of life [34]. Although questionnaires related to the SEAR questionnaire have merit [33 36], a salient feature of the SEAR questionnaire is its emphasis on confidence, relationship, and especially self-esteem [20,23]. Three independent clinical trials suggest that the SEAR questionnaire is robust in detecting substantial changes related to relationships, confidence, and particularly self-esteem after successful treatment with sildenafil [20 22]. Studies using the EDITS index indicate its validity in measuring patient satisfaction with different treatment options for ED [25 27]. Because it measures interrelated facets of treatment satisfaction, the multiitem EDITS has better validity and reliability than a single-item measure of treatment satisfaction [24]. The current report is the first to examine the association between the EDITS index and the SEAR questionnaire and, to our knowledge, the first to examine the association between a measure of treatment satisfaction for ED therapy and an ED-specific measure of psychological well-being and functioning. The data indicate a high correspondence of treatment satisfaction with enhanced self-esteem, confidence, and relationship for sildenafil-naïve patients who were later given sildenafil in an openlabel clinical trial. These results hold promise that, like treatment satisfaction, improvements in selfesteem, confidence, and relationships may also be an important consideration in maintaining longterm therapy for ED. Limitations of this single-treatment, open-label study are the lack of placebo control and the lack of blinding. These limitations might have predisposed patients toward a successful study outcome, resulting in artificially high scores and correlations between treatment satisfaction and psychosocial indicators. Nevertheless, two subsequent randomized, double-blind, placebo-controlled trials [21,22] demonstrated that sildenafil resulted in considerable gains, above and beyond placebo, on the SEAR questionnaire and on standard measures of clinical efficacy like the IIEF [37]; correlations between these standard measures and the SEAR questionnaire were moderate to high in general [21,22]. Although treatment satisfaction was not assessed in those two randomized trials, it is quite likely that treatment satisfaction would have maintained a high level of association with psychosocial factors similar to that found in the open-label study, given the relatively high level of interrelationships among the EDITS index, the SEAR questionnaire, the IIEF, and other measures of clinical efficacy obtained from existing studies.

6 EDITS/SEAR Association Conclusions The correlations between scores on the SEAR questionnaire and the EDITS index are statistically significant and substantial. The data attest to a moderate-to-high positive association between treatment satisfaction and psychosocial benefit among men with ED treated with sildenafil. Our research has demonstrated an important triangle among efficacious treatment of ED (in erectile and sexual function), treatment satisfaction (patients like the way the treatment works for them), and improvements in disease-specific parameters related to quality of life. Psychosocial factors self-esteem, confidence, and relationships as measured by the SEAR questionnaire, a disease-specific questionnaire for men with ED, show discernible separation in the expected direction for varying levels of treatment satisfaction, as measured by the EDITS index. More satisfaction with ED treatment is associated with more confidence, more self-esteem, and better relationships in men with ED. Further research is encouraged to go beyond such an association to formally examine a hypothesis of causality from treatment satisfaction to improved psychosocial factors; for such a purpose, structural equation models can be employed in future studies. In the meanwhile, the results of this study provide further evidence for the validity of the SEAR questionnaire and highlight the importance of assessing the psychosocial impact of ED among men undergoing treatment for this disorder. The authors thank Arkady Shpilsky, PhD; Caryn Diuguid, RN, MS; and Michael Sweeney, MD, FRCP, for their contributions to this study. Source of financial support: Pfizer Inc References 1 NIH Consensus Development Panel on Impotence. NIH consensus conference. Impotence. JAMA 1993;270: Feldman HA, Goldstein I, Hatzichristou DG, et al. Impotence and its medical and psychosocial correlates: results of the Massachusetts Male Aging Study. J Urol 1994;151: Hultling C, Giuliano F, Quirk F, et al. Quality of life in patients with spinal cord injury receiving Viagra (sildenafil citrate) for the treatment of erectile dysfunction. Spinal Cord 2000;38: Lowentritt BH, Scardino PT, Miles BJ, et al. Sildenafil citrate after radical retropubic prostatectomy. J Urol 1999;162: S59 5 Montorsi F, McDermott TED, Morgan R, et al. Efficacy and safety of fixed-dose oral sildenafil in the treatment of erectile dysfunction of various etiologies. Urology 1999;53: Conti CR, Pepine CJ, Sweeney M. Efficacy and safety of sildenafil citrate in the treatment of erectile dysfunction in patients with ischemic heart disease. Am J Cardiol 1999;83: Seidman SN, Roose SP, Menza MA, et al. Treatment of erectile dysfunction in men with depressive symptoms: results of a placebo-controlled trial with sildenafil citrate. Am J Psychiatry 2001;158: Olsson AM, Persson CA. Efficacy and safety of sildenafil citrate for the treatment of erectile dysfunction in men with cardiovascular disease. Int J Clin Pract 2001;55: Rendell MS, Rajfer J, Wicker PA, et al. Sildenafil for treatment of erectile dysfunction in men with diabetes. JAMA 1999;281: Solomon H, Man JW, Jackson G. Erectile dysfunction and the cardiovascular patient: endothelial dysfunction is the common denominator. Heart 2003;89: O Kane PD, Jackson G. Erectile dysfunction: is there silent obstructive coronary artery disease? Int J Clin Pract 2001;55: Kaiser DR, Billups K, Mason C, et al. Impaired brachial artery endothelium-dependent and independent vasodilation in men with erectile dysfunction and no other clinical cardiovascular disease. J Am Coll Cardiol 2004;43: Shabsigh R, Anastasiadis AG. Erectile dysfunction. Annu Rev Med 2003;54: Korenman SG. New insights into erectile dysfunction: a practical approach. Am J Med 1998;105: World Health Organization. About WHO. WWW document: Available from: about/en/. [Accessed July 20, 2004]. 16 Althof SE. Quality of life and erectile dysfunction. Urology 2002;59: Fowler CJ, Miller JR, Sharief MK, et al. A double blind, randomised study of sildenafil citrate for erectile dysfunction in men with multiple sclerosis. J Neurol Neurosurg Psychiatry 2005;76: Giuliano F, Peña BM, Mishra A, et al. Efficacy results and quality-of-life measures in men receiving sildenafil citrate for the treatment of erectile dysfunction. Qual Life Res 2001;10: Paige NM, Hays RD, Litwin MS, et al. Improvement in emotional well-being and relationships of users of sildenafil. J Urol 2001;166: Althof SE, Cappelleri JC, Shpilsky A, et al. Treatment responsiveness of the self-esteem and relationship questionnaire in erectile dysfunction. Urology 2003;61: Cappelleri JC, Duttagupta S, Sherman N, et al. Self-esteem, confidence, and relationships in men

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