Male Erectile Dysfunction and Health-Related Quality of Life $

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1 European Urology European Urology 44 (2003) Male Erectile Dysfunction and Health-Related Quality of Life $ J.J. Sánchez-Cruz a, A. Cabrera-León a, A. Martín-Morales b, A. Fernández a, R. Burgos b, J. Rejas c,* a Andalusian School of Public Health, Granada, Spain b Urology Department, Hospital Carlos Haya, Málaga, Spain c Health Outcomes Research, Medical Unit, Pfizer SA, Parque Empresarial de la Moraleja, Avenida de Europa, 20-B, Alcobendas, Madrid, Spain Accepted 22 April 2003 Abstract Objective: The purpose of this work was to assess the health-related quality of life factors associated with erectile dysfunction (ED). Methods: 2476 non-institutionalised Spanish males, age ranging from 25 to 70 years, were interviewed. ED was defined using two instruments: a simple self-assessment question (ED-sq) and the International Index of Erectile Function (IIEF). Health-related quality of life (HRQoL) was measured through the SF-36 questionnaire. Results: The severity of ED (measured both through the ED-sq and with the IIEF) increased as the scores of the scales of the SF-36 decreased (Mantel Hänszel w 2 -test statistic range: [26 305]; p < 0:001). The two summary components (physical and mental) showed a downward trend, more for the physical than for the mental component. Conclusion: We found a clear pattern of negative association between self-perceived erectile dysfunction and HRQoL. This association was clearer when ED-sq (rather than IIEF) was used, and stronger for the physical summary component than for the mental one. # 2003 Elsevier Science B.V. All rights reserved. Keywords: Erectile dysfunction; Quality of life; SF-36 questionnaire; IIEF 1. Introduction Erectile dysfunction (ED) is a serious public health problem affecting millions of citizens and their quality of life [1,2]. The directly proportional correlation between the age of the subjects and both the probability of suffering erectile dysfunction and its degree of severity is widely documented [3,4]. As the populations of the Organization for Economic Cooperation Development (OECD) countries are aging but maintaining their interest in sex [5,6], erectile dysfunction has acquired greater significance as a public health problem, to which the health systems and policies must $ The results shown here are part of the EDEM study (J Urol 2001, 166: ), which was supported by an unrestricted grant from Pfizer S.A. * Corresponding author. Tel. þ ; Fax: þ address: javier.rejas@pfizer.com (J. Rejas). devote an increasing amount of attention and resources. In the last decade, measurements of health-related quality of life (HRQoL) have gained great relevance in the study of the health status of patients and populations and in the evaluation of both the quality of clinical and health care in general and the efficacy of public health interventions. This has been the result of an historic evolution in the concept of health, which, under the influence of both biomedical and social sciences and of environmental movements, has become more complex and multidimensional [7]. Currently, we are not only concerned with the traditional clinical aspects of the disease presumably more objective but also with other more subjective dimensions, in agreement with the definition of health made by the WHO [8], related to the degree of the individual s physical, social or emotional function, and which considers the satisfaction and well-being of patients in relation to their health /$ see front matter # 2003 Elsevier Science B.V. All rights reserved. doi: /s (03)00215-x

2 246 J.J. Sánchez-Cruz et al. / European Urology 44 (2003) as perceived by the individuals themselves. This is known as the health-related quality of life (HRQoL) [9]. This study was made in the context of the EDEM project (Epidemiología de la Disfunción Eréctil Masculina [4], which investigates the prevalence and independent risk factors for Erectile Dysfunction in Spain) and its objective was to establish the HRQoL factors associated with erectile dysfunction. 2. Methods 2.1. Design This is a population-based, prevalence study in which the target population consists of Spanish men aged from 25 to 70 years inclusively, taken from the community at large, who are not institutionalised and who are resident in the Spanish peninsula. A probabilistic, multistage sampling design was used, with stratification of the primary sampling units. The primary sampling units were census section, then secondary sampling units were dwellings and the final sampling units were subjects. The stratification was based on age group (25 39 years, years, years, and years), autonomous community with 15 levels corresponding to each peninsular autonomous community and population density with 4 levels, including fewer than 10,000, 10,001 to 50,000, 50,001 to 500,000 and more than 500,000 inhabitants or provincial capitals. The sample setting was proportional to the number of men included in each population stratum. In all, for the study population, the overall sample contained 2476 men. (A detailed description of the sampling design and data collection can be found in [4].) 2.2. Erectile dysfunction definition This study used two criteria to define male erectile dysfunction. Question 16 (Table 1), based on the subject s overall self-assessment of his erectile capacity ( simple question ), was used as the first defining criterion of the different degrees of erectile dysfunction (ED-sq). This simple question was worded as follows: Do you consider yourself a man...(a) with no erection problem;(b) with a minimal incapacity; (c) with a moderate incapacity; (d) with a severe/complete incapacity for erection?. The second criterion defining the different degrees of ED is the score of the answers to questions 1 5 and 15 (Table 1) of the International Index of Erectile Function (IIEF) [10,17] which form the erectile function domain of the IIEF (EF-IIEF), according to the following scale: 26 to 30 no dysfunction, 17 to 25 mild dysfunction, 11 to 16 moderate dysfunction, and 6 to 10 severe/complete dysfunction (ED-IIEF). SF-36 was the questionnaire used to measure health-related quality of life (HRQoL) in this study [11,12]. It includes 36 items addressing eight health concepts (scales; physical functioning, social functioning, role-physical, bodily pain, general mental health, role-emotional, vitality, general health perceptions), and two summary measurements (summary components): physical health and mental health. The survey was designed for self-administration by persons of 14 years of age and over, and for administration by trained interviewers, in person and by telephone. The scores for each of the 8 dimensions (scales) are coded, added up and transformed to a scale from 0 to 100, where the higher the score, the better the state of health. It has been validated for Spain [13] Data analysis A descriptive analysis was made of each scale and summary component of the SF-36 scale, giving measurements of a central tendency and of dispersion (mean, median and standard deviation), for the overall sample and for each age group sub-sample (25 39 years, years, years, years). Spearman s correlation coefficient (r) was used to study the association between age and the profiles and components of the SF-36 scale. A Mantel Hänszel w 2 -test (M H) was used to assess the trend between the score obtained in the SF-36 scale and the degree of dysfunction. Line figures were also used for visual representation of the trend. To study the association between the SF-36 scale and the dysfunction a Student s t-test was made (after performing Levene s homocedasticity test). A stratification by the age group variable Table 1 List of questions of erection capacity used in the EDEM study. It includes Erectile Domain of the International Index of Erectile Function (IIEF, questions 1 to 5 plus 15), and the Simple Question -ED-sq- (question 16 of the questionnaire) List of questions of erection capacity Q.1. Q.2. Q.3. Q.4. Q.5. Q.6. Q.7. Q.8. Q.9. Q.10. Q.11. Q.12. Q.13. Q.14. Q.15. Q.16. Over the past 4 weeks, how often were you able to get an erection during sexual activity? Over the past 4 weeks, when you had erections with sexual stimulation, how often were your erections hard enough for penetration? Over the past 4 weeks, when you attempted sexual intercourse, how often were you able to penetrate your partner? Over the past 4 weeks, during sexual intercourse, how often were you able to maintain your erection after you had penetrated your partner? Over the past 4 weeks, during sexual intercourse, how difficult was it to maintain your erection to the completion of intercourse? Over the past 4 weeks, how many times have you attempted sexual intercourse? Over the past 4 weeks, when you attempted sexual intercourse, how often was it satisfactory for you? Over the past 4 weeks, how much have you enjoyed sexual intercourse? Over the past 4 weeks, when you had sexual stimulation or intercourse, how often did you ejaculate? Over the past 4 weeks, when you had sexual stimulation or intercourse, how often did you have the feeling of orgasm or climax (with or without ejaculation)? Over the past 4 weeks, how often have you felt sexual desire? Over the past 4 weeks, how would you rate your level of sexual desire? Over the past 4 weeks, how satisfied have you felt with your overall sex life? Over the past 4 weeks, how satisfied have you been with your sexual relationship with your partner? Over the past 4 weeks, how do you rate your confidence that you can achieve and maintain your erection? Do you consider yourself a man...(a) With no erection problem; (b) With a minimal incapacity; (c) With a moderate incapacity; (d) With a severe/ complete incapacity for erection.

3 was also used in order to identify the potential modifying effect of age on the association obtained between the SF-36 scale and the dysfunction. The 95% confidence level was used. SPSS 10 statistical software [18] was used for all the analyses and figures. J.J. Sánchez-Cruz et al. / European Urology 44 (2003) Results Participation rate was 75% (n ¼ 2476 subjects), and 12.1% (95% CI: 10.8% 13.3%), of men showed some degree of ED: 5.2% mild, 5% moderate and 1.9% severe/complete when simple question is used and 18.9% (95% CI: 17.2% 20.7%) when IIEF instrument is applied to assess ED prevalence. Sociodemographic characteristics were similar between subjects with and without erectile dysfunction. Table 2 shows the ageadjusted odd ratios (ORs) of the different physical and sociodemographic characteristics analyzed, none of which appear to be related to erectile dysfunction. The mean scores obtained in SF-36 by subjects with ED were significantly lower than in subjects without ED, and mean differences ranged between 7.5% and 16.5% ( p < 0:01 to p < 0:001, Fig. 1). The score most closely related to ED is that of the scale corresponding to the physical function (Spearman r ¼ 0:35). The rest of the scales also related negatively although to a lesser extent. The summary scales of physical and mental components showed significantly lower scores in subjects with ED than in those without ED ( p < 0:01 in both cases, Fig. 2), with the most significant difference being in the physical component. Adjusted Odds Ratio for standardised components were 0.93 ( ) for Table 2 OR (age-adjusted) according to physical and sociodemographic characteristics of suffering some degree of erectile dysfunction Fig. 1. Radial chart showing SF-36 domains mean values between subjects with (&, n ¼ 295) and without (*, n ¼ 2160) erectile dysfunction from the EDEM study [4]. PF: Physical functioning, SF: Social functioning, RP: Role-physical, BP: Bodily pain, MH: General mental health, RE: Role-emotional, V: Vitality, GH: General health perceptions. p < 0:01, p < 0:001. physical and 0.94 ( ) for mental. Spearman s correlation coefficient sign was negative in all the associations of age with the different scales and components of the SF-36 scale, suggesting that the older the subjects, the lower the score in all the scales (that is, a poorer health-related quality of life). The strongest associations were observed with the physical function scale and with the physical summary component ( r ¼ 0:475 and respectively; p < 0:001). Non-significant associations were obtained with the mental health, role-emotional and social function scales Characteristics Adjusted OR (95% CI) Height in cm 0.99 ( ) Weight in kg 1.00 ( ) Body volume 1.03 ( ) Educational level Can neither read nor write 1.06 ( ) Has no educational certificates 1.00 ( ) Primary education, VT I 0.97 ( ) Secondary education, VT II 0.97 ( ) College studies 0.88 ( ) Degree studies 1 Monthly income * Fewer than 50,000 PTA 1.91 ( ) From 50,001 to 70,000 PTA 0.88 ( ) From 70,001 to 90,000 PTA 1.17 ( ) From 90,.001 to 150,000 PTA 1.29 ( ) From 150,001 to 200,000 PTA 0.71 ( ) More than 200,000 PTA 1 * Currency in Spanish pesetas (PTA). Fig. 2. Bar chart showing SF-36 mental and physical summary components mean values (with 95% confidence intervals) between subjects with (n ¼ 295) and without (n ¼ 2160) erectile dysfunction from the EDEM study [4]. p < 0:01.

4 248 J.J. Sánchez-Cruz et al. / European Urology 44 (2003) Fig. 3. SF-36 domains mean values according to ED-sq degree of severity. PF: Physical functioning, SF: Social functioning, RP: Role-physical, BP: Bodily pain, MH: General mental health, RE: Role-emotional, V: Vitality, GH: General health perceptions. Fig. 4. SF-36 domains mean values according to ED-IIEF degree of severity. PF: Physical functioning, SF: Social functioning, RP: Rolephysical, BP: Bodily pain, MH: General mental health, RE: Roleemotional, V: Vitality, GH: General health perceptions. (r ¼ 0:006, and 0.064) and with the mental component (r ¼ 0:052). As shown in Fig. 3, the degree of erectile dysfunction (ED-sq) increases as the scores of the SF-36 decrease (M H range: [54 305]; p < 0:001). The vitality and general health scales show lower scores for any dysfunction level. The higher scores appear in the roleemotional and social function scales. If we analyse the trend between the two summary components (physical and mental) of the SF-36 scale and the degree of erectile dysfunction according to ED-sq levels, we find (as in the scales) a downward trend, more marked for the physical than for the mental component (M H ¼ and 44.6 respectively, p < 0:001). The physical component ranges from a maximum value of 52.9 for subjects with no dysfunction to a minimum value of 39.5 for those with severe dysfunction. The mental component progresses from a maximum of 51.8 for subjects with no dysfunction to a minimum of 48 for those with severe dysfunction. Fig. 4 shows a descending correlation between the scores of the different scales in the SF-36 questionnaire and the degrees of erectile dysfunction (according to the erectile function domain of the international index, ED-IIEF) (M H range ¼ [ ], p < 0:001). As with the simple question (ED-sq) the vitality and general health scales are the ones with the lowest scores for any degree of dysfunction, whereas the role-emotional and social function scales show the highest values. In the roleemotional scale, moderate erectile dysfunction obtains a mean score that is well below the rest of the degrees of dysfunction. On analysing the trend between the two summary components (physical and mental) of the SF-36 questionnaire and the degree of erectile dysfunction according to ED-IIEF levels, we find a downward trend (as with the scales), more marked for the physical than for the mental component (M H ¼ and respectively, p < 0:001). The physical component ranges from a maximum of 53.6 for subjects with no dysfunction to a minimum value of 42.3 for those with severe dysfunction, whereas the mental component ranges from a maximum of 52.3 for subjects with no dysfunction to a minimum of 48.9 for those with severe dysfunction. In view of the small sample size of the different subgroups when simultaneously separated based on the degree of dysfunction and age group variables, we decided, when making the corresponding statistical analysis to control any potential confounding effects of age, to recode the dysfunction level variable at just two levels: erectile dysfunction (yes, no). Table 3 shows mean scores differences in each scale of the SF-36 between subjects with and without erectile dysfunction according to the simple question and with stratification by the age group variable. The youngest age group (25 39 years) showed the greatest difference in mean scores in each scale of the SF-36 questionnaire, except for the physical function scale, where greater differences were found in the year age group. In all scales, there is a difference of more than

5 J.J. Sánchez-Cruz et al. / European Urology 44 (2003) Table 3 Mean scores differences in each scale of the SF-36 between subjects with and without erectile dysfunction according to the simple question (ED-sq), and with stratification by the age group variable Health domain Age groups Levine s homocedasticity test T test for equality of means F Sig. t df Sig. (bilateral) Difference in mean scores SE of difference 95% CI for the difference Lower Upper Physical function From 25 to 39 years From 40 to 49 years From 50 to 59 years From 60 to 70 years Role-physical From 25 to 39 years From 40 to 49 years From 50 to 59 years From 60 to 70 years Bodily pain From 25 to 39 years From 40 to 49 years From 50 to 59 years From 60 to 70 years General health From 25 to 39 years From 40 to 49 years From 50 to 59 years From 60 to 70 years Vitality From 25 to 39 years From 40 to 49 years From 50 to 59 years From 60 to 70 years Social function From 25 to 39 years From 40 to 49 years From 50 to 59 years From 60 to 70 years Role-emotional From 25 to 39 years From 40 to 49 years From 50 to 59 years From 60 to 70 years Mental health From 25 to 39 years From 40 to 49 years From 50 to 59 years From 60 to 70 years Physical component From 25 to 39 years From 40 to 49 years From 50 to 59 years From 60 to 70 years Mental component From 25 to 39 years From 40 to 49 years From 50 to 59 years E From 60 to 70 years points. The year age group showed the least difference for the physical function, general health, vitality, social function and role-emotional scales (being higher than 5 points in all cases). The year age group showed the least difference in all other scales. The scale with the greatest differences in score between subjects with and without dysfunction in all age groups was the role-physical scale, with differences of around 20 points. By contrast, the scale with the fewest differences was that of mental health, except for the year age group, in which a difference greater than 20 points was found. There was no specific trend in the different scores in any of the scales across the age groups.

6 250 J.J. Sánchez-Cruz et al. / European Urology 44 (2003) The behaviour shown in the EF domain of the IIEF was not as clear as in the single question when it came to assessing the score differences for each scale and age group. For the mental scales (vitality, social function, role-emotional and mental health) and for general health the most extreme age groups (25 39 and years) were the ones with the greatest score differences. In the rest of the scales there were no age groups that stood out from the rest. The score differences found for the EF domain were smaller than those found by the simple question (Table 4). With the single question, in the physical component of SF-36, score differences of the same size and statistically significant were obtained between no dysfunction and dysfunction Table 4 Mean scores differences in each domain of the SF-36 between subjects with and without erectile dysfunction according to International Index of Erectile Function questionnaire (ED-IIEF), and with stratification by the age group Health domain Age groups Levine s homocedasticity test T test for equality of means F Sig. t df Sig. (bilateral) Difference in mean scores SE of difference 95% CI for the difference Lower Upper Physical function From 25 to 39 years From 40 to 49 years From 50 to 59 years From 60 to 70 years Role-physical From 25 to 39 years From 40 to 49 years From 50 to 59 years From 60 to 70 years Bodily pain From 25 to 39 years From 40 to 49 years From 50 to 59 years From 60 to 70 years General health From 25 to 39 years From 40 to 49 years From 50 to 59 years From 60 to 70 years Vitality From 25 to 39 years From 40 to 49 years From 50 to 59 years From 60 to 70 years Social function From 25 to 39 years From 40 to 49 years From 50 to 59 years From 60 to 70 years Role-emotional From 25 to 39 years From 40 to 49 years From 50 to 59 years From 60 to 70 years Mental health From 25 to 39 years From 40 to 49 years From 50 to 59 years From 60 to 70 years Physical component From 25 to 39 years E From 40 to 49 years E From 50 to 59 years From 60 to 70 years Mental component From 25 to 39 years From 40 to 49 years From 50 to 59 years From 60 to 70 years

7 J.J. Sánchez-Cruz et al. / European Urology 44 (2003) (Table 3). However, when the EF domain of the IIEF scale was used (Table 4), no significant differences were observed in the lower age groups (25 39 and years), whereas there was a real statistical significance in the and age groups. The score differences seen in the IIEF scale were lower than those in the single question. When we established the dysfunction through the single question, we found that the mental component of SF-36 showed statistically lower (poorer) values in subjects with dysfunction for all age groups. Moreover, these differences, between dysfunction and no dysfunction, in said component become lower the higher the age group (Table 3), decreasing until they become stable in subjects over 50 years. The EF domain of the IIEF scale (Table 4) shows a similar behaviour to the simple question, except that the differences in the and age groups are not statistically significant. 4. Discussion We found a clear pattern of negative association between self-perceived erectile dysfunction and health-related quality of life, this association being more apparent when ED-sq was used for measuring the degree of EF than when erectile condition was ascertained through the erectile domain of the IIEF. This pattern of negative association is more apparent for the physical summary component of the SF-36 than for the mental one. Although the data strongly suggest that this effect may be different according to the age of the subject, differences in health-related quality of life scores being more significant in younger ages than in older ones, we cannot confidently state that it is an effect modification because of the difficulties in applying appropriate statistical tests, given data distribution. The epidemiological studies on ED conducted to date have been based mainly on the subject s own assessment by way of an overall simple question as a criterion for establishing erectile dysfunction (ED-sq). However, since this is a question of individual perception, an assessment that uses a multidimensional scale (ED-IIEF) would appear more accurate in its ability to detect ED. Recent studies have shown a substantial correlation between both measurements of ED, which, as was to be expected in view of their different composition, is far from perfect [4,15 17]. Therefore, the values obtained in our case are not identical. However, the pattern of results is very similar when we measure the ED through the simple question or using the erectile dysfunction domain of the IIEF, thus giving greater weight to our findings. The purpose of our study also led us to stress the convergence of the results in the essentials, rather than trying to explain the accessorial and inevitable divergences between two different forms of measuring the same event. SF-36 is one of the most widely used of the HRQoL measurements. It was designed to provide assessments involving generic health concepts that are not specific to any age, disease or treatment group, and places emphasis upon physical, social and emotional functioning. It was designed for use in clinical practice and research, health policy evaluations and general population surveys. As a result of the major trade-off between breadth and depth of measurement, important health concepts are not represented in the SF-36, such as family, cognitive functioning, or sleep disorders, but its increasing use as one of the reference questionnaires for establishing HRQoL allows the results to be compared with those of other studies, providing greater scientific knowledge in this area. This is a cross-sectional study conducted in a representative sample of the Spanish population. The fact that we obtained a higher response rate (75%), similar to other epidemiological studies performed on this issue (i.e. Jonler s study reported a response rate in 1995 of 90%, the Italian study on prevalence of ED showed a value of 82%, the Massachusetts Male Aging Study (MMAS) had a 75%, and the National Health and Social Life Survey (NHSLS) reported a figure of 79%) indicates that the EDEM study also succeeded in producing a truly representative sample of the population [23 26]. This should endorse to our study of a considerable reliability of observed results about the impact of ED on subject s quality of life. However, we cannot establish the direction of the association. We found that males with erectile dysfunction simultaneously experienced a poorer perception of healthrelated quality of life. Although we did not address the epistemological level of physiopathologic mechanisms involved in ED and HRQoL, and how they may relate to each other, it is not likely that dysfunction causes an impairment in physical function, or viceversa, but it is probable that when they are concurrent, they are both caused by physiological and, to some extent, common disorders. By contrast, it is possible that a poorer state of mental health can cause psychogenic ED, and that inversely, ED can cause a poorer state of mental health (which the psychological maturity of old age and the lower, although existent, sexual expectations may mitigate) [14]. There are few studies to date on the quality of life of subjects with ED that have used the same definitions of the concepts studied and identical measuring instruments, with a view to allowing the comparison of the same. Nevertheless, the most general findings resulting

8 252 J.J. Sánchez-Cruz et al. / European Urology 44 (2003) from our study are consistent with other previous studies that have shown an association of male erectile dysfunction with health status and emotional function [18,19], or with the existence of stress or emotional problems, and with low levels of general health and of physical or emotional satisfaction [19]. Other studies also suggest the association of psychological variables with erectile dysfunction: men with the highest levels of anger suppression and anger expression had higher probabilities of moderate and complete erectile dysfunction than the overall study population, as well as men with the greatest degree of depression [20]. Fugl- Meyer et al. [14] found that the level of satisfaction with sexual life is very low in men who seek professional help for their erectile dysfunction and a significant increase in the level of sexual satisfaction by successful intracavernosal treatment. Araujo et al. [21] concluded that the relationship between depressive symptoms and male erectile dysfunction in middleaged men was robust. Another surprising finding was the relatively high Social Functioning associated to severe ED as showed in Fig. 4 when IIEF is used. It is difficult to explain this finding as it was not shown the same value according to ED-sq degree of severity. A explanation could be that in the EDEM study, social functioning was unrelated with age, in fact, the younger male even shown a worst social functioning than older men (higher differences between non-ed and ED subjects at youngest segments of age, see Tables 3 and 4). Since the degree of ED determined by ED-sq does not match exactly with the degree assessed by IIEF, moderate ED patients assessed by IIEF could correspond to younger people than moderate ED patients determined by ED-sq. All these studies reveal that men who suffer erectile dysfunction also show a poorer quality of life, in both its physical and psychological or mental dimensions, although it is true that the studies mentioned have different approaches when defining and measuring erectile dysfunction and quality of life. On the one hand, this provides multiple findings proceeding from different ways of measuring the event which support the negative association between erectile dysfunction and quality of life, but on the other hand, it hinders the quantification of the event and the comparison of the relevant literature. Thus, Litwin et al. [22] studied HRQoL in men with erectile dysfunction, using the SF-36 to assess general HRQoL. Like us, they found that erectile dysfunction was associated with the physical and psychophysical function more than in the normal population. However, unlike our study, they found that emotional domains of SF-36 were more deeply affected than were physical domains in subjects with erectile dysfunction. In the absence of other studies to date which, with the same measuring instruments, could provide additional information, a possible explanation for this disparity in the results is not only the different cultural settings where the two studies have been conducted, but also the fact that, in the case of Litwin et al., the findings are based on a nonrepresentative sample in population terms, restricted to very specific groups, which could potentially limit the generalized nature of their findings and which, moreover, is very small in size (a sample somewhat larger than that of these authors at the different levels of erectile dysfunction led us, unlike them, to renounce making inferences and comparisons between these groups to avoid statistical artifacts). In order to be able to compare the multiple studies being conducted in this field and to achieve greater knowledge of the HRQoL associated with dysfunction, it is necessary to homogenize the definition of the events (in this case ED and HRQoL) and the instruments for measuring them. Our results show a consistent concurrence between HRQoL and male erectile dysfunction and suggest that erectile function may be one of the components for males to be considered when approaching healthrelated quality of life improvement. Future studies could address the issue of whether or not an adequate management of erectile dysfunction affects self-perceived health-related quality of life. References [1] NIH Consensus Development Panel on Impotence. Impotence. JAMA. 1993;270: [2] The likely worldwide increase in erectile dysfunction between 1995 and 2025 and some possible policy consequences BJU Int 1999;84(1): [3] Feldman HA, Goldstein I, Hatzichristou DG, Krane RJ, McKinlay JB. 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