Large‐scale questionnaire survey of erectile dysfunction drugs in Japanese men

Abstract

Aim:  The aim of the present study was to investigate the assessment of currently prescribed drugs and approaches to overall erectile dysfunction (ED) therapy.

Methods:  A large‐scale questionnaire survey was conducted in patients with ED who had taken an ED drug in the past 2 months.

Results:  Of the 308 patients surveyed, 23% became aware of having ED more than 3 years ago. In the early stages, the patients frequently experienced ‘anxiety and a sense of loss’ and ‘irritation and powerlessness’. The ED drugs taken were sildenafil and vardenafil in 65 and 31% of the patients, respectively. Although their efficacy was generally high, approximately 80% of the patients (younger patients in particular) experienced some problems with these medications. As negative assessments, the difficulty in finding a good time to take the drug and the strange sensation of the drug forcing the patient to have an erection were pointed out.

Conclusion:  Use of an ED drug such as tadalafil, which produces long‐lasting effects and allows more spontaneity in sexual activity, will improve ED symptoms in a favorable manner, and will not only improve the self‐image of the ED patients, leading to activation and fulfillment of their lives as a whole, but will also enhance the satisfaction and security of their partners. (Reprod Med Biol 2008; 7: 105–114)

INTRODUCTION

ACCORDING TO AN epidemiological survey conducted by Shirai ¹ in 2002, the number of men aged 30–79 years with erectile dysfunction (ED) in Japan was 11.3 million – a similar prevalence rate to that in the US adult male population. ² However, a health survey of men conducted by Shinoyama et al. ³ in 2001 revealed that only 10% of Japanese individuals with ED had received treatment. At that time, the significance of ED and its therapeutic drugs were not widely understood by medical institutions in Japan, although the phosphodiesterase 5 (PDE5) inhibitor sildenafil citrate (Viagra; Pfizer, New York, NY, USA) had been available for use since 1999. Soon after the launch of sildenafil, another PDE5 inhibitor, vardenafil hydrochloride hydrate (Levitra; Bayer Schering Pharma AG, Berlin, Germany), was launched in 2004, followed by tadalafil (Cialis; Eli Lilly, Indianapolis, IN, USA) in 2007. Thus, a variety of ED drugs are currently available in Japan. In addition, through public enlightenment activities concerning ED and its treatment, ED is becoming accepted as a tractable condition.

Erectile dysfunction has been shown to be highly correlated not only with advanced age, but also independently with overall health. ⁴ Conventionally, the criteria for the efficacy of ED drugs have been set mechanistically as, for example, ‘penile rigidity’ and ‘maintenance of an erection’. ⁵ However, under the current situation where ED treatment has been generalized and the ED drug market has matured to some extent, ED patients are seeking not only sexual satisfaction, but also spontaneity in sexual activity. In other words, men desire not only to have an erection sufficient for successful sexual intercourse with the use of ED drugs, but also to return to their sexual performance in a pre‐ED state by restoring their self‐confidence; patients want to perform spontaneous sexual activities in their daily living without experiencing impatience or pressure. Considering the above, anti‐ED treatment should be regarded as an important part of positive health management for men.

In the present study, we conducted a nationwide questionnaire survey using the Internet to identify the level of satisfaction felt by patients on currently prescribed ED drugs and to assess the attitudes of patients receiving anti‐ED treatment. In addition, we discuss changes in the levels of satisfaction felt by patients on ED drugs based on our survey results.

METHODS

THE SURVEY WAS conducted in ≥20‐year‐old ED patients who desired to improve their symptoms and had been prescribed sildenafil or vardenafil within the past 2 months.

The survey was conducted nationwide using the Internet. Screening for ED was carried out by a survey panel from the Internet research agency Macromill (Tokyo, Japan). Screening was designed to close when the number of respondents to the questionnaire reached 50 000. Apart from having received an anti‐ED drug in the past 2 months, patients who answered ‘yes’ or ‘somewhat’ to questions such as whether they had ‘concern about penile rigidity and maintenance of erection’, ‘occasional difficulty with penetration due to insufficient rigidity of erection during sexual intercourse’, and ‘occasional difficulty in maintaining an erection during sexual intercourse’ during screening were examined in the present survey. The survey contained 15 major items (see Appendix I), including initial ED status, assessment of the currently prescribed drug and approaches to overall ED therapy.

In the tabulation of the survey results, the total percentage of the top three answers was taken as the response rate for the following five major items: feelings when becoming aware of ED symptoms, reasons for taking an ED drug, feelings when taking an ED drug, attitudes towards ED drugs, and lifestyle and approaches to sex life.

RESULTS

Screening

THE SURVEY WAS started on 3 July 2007. As 50 000 respondents were obtained in 2 days, the survey ended on 4 July 2007.

In the screening, the percentage of respondents who answered positively to having ‘concern about penile rigidity and maintenance of erection’ was 33.2%, whereas the percentages for having ‘occasional difficulty with penetration due to insufficient rigidity of erection during sexual intercourse’ and ‘occasional difficulty in maintaining an erection during sexual intercourse’ were 27.1 and 21.2%, respectively. Positive response rates tended to increase with advancing age: 40–50% of respondents aged in their 60s and 50–60% aged ≥70 years responded positively to these items.

Of the patients who answered ‘yes’ or ‘somewhat’ to these three issues, those who indicated a ‘strong desire for improvement’ and ‘desire for improvement’ accounted for 60.0% of the total respondents. The percentage of such respondents was consistent among age groups.

Actions taken against symptoms were: ‘purchase of Chinese herbal medicines, nutritional supplements, dietary supplements, or sexual vitalizers or tonics from a pharmacy or drugstore’ in 11.4%; ‘search for information on ED and therapeutic drugs’ in 10.1%; ‘purchase of Chinese herbal medicines, nutritional supplements, dietary supplements, or sexual vitalizers or tonics by mail order’ in 9.9%; and ‘purchase of ED drugs (sildenafil, vardenafil) from a hospital or clinic’ in 3.7% of respondents.

Survey

Of the 50 000 participants screened, 308 patients entered the present survey. They had a wide distribution in age from 25 to >60 years. When examined in age groups in 5‐year intervals, patients aged 45–49 years accounted for the highest percentage (21.1%). Younger individuals aged 25–39 years accounted for 44.5%. With respect to their occupations, company employees accounted for 66.6%. With respect to their residential areas, although Kanto, Kinki and Chubu regions accounted for 80% of respondents, the entire country was covered.

The time of becoming aware of having ED was >3 years ago in 23% of the patients surveyed, and the percentage tended to be higher in middle‐aged and elderly patients. In more than half of the younger population aged 20–39 years, this parameter was <1 year. In contrast, oral ED medication started within <3 months in approximately half of these individuals, and started ≥1‐year later in >40% of patients aged in their 40s and 50s.

Regarding their feelings at the time of becoming aware of the subjective symptoms, markedly high response rates were obtained for experiencing ‘anxiety and sense of loss that I have physically deteriorated considerably’ (81.8%) and ‘irritation and sense of powerlessness regarding the inability to satisfy my partner’ (73.4%). Comparisons among age groups showed a trend that a high positive response rate to these items was applicable to patients aged in their 30s.

Sildenafil and vardenafil were taken by 65% and 31% of respondents, respectively. This distribution is similar to the prescription ratio of these two drugs in Japan. Prescription of sildenafil was particularly high (80%) in patients aged in their 20s and 30s. In contrast, medication with vardenafil was higher in patients aged ≥40 years.

The number of tablets prescribed at each medical examination was 3–5 in >60% of patients aged in their 20s and 30s, whereas it was ≥10 tablets in a high percentage (approximately 45%) of patients aged in their 40s and 50s (Fig. 1). The mean number of tablets taken per month in the past 6 months was <2 in the highest percentage (42%) of patients, whereas it was ≥3 in >40% of patients aged in their 40s (Fig. 2).

Figure 1.

Number of tablets prescribed at each medical examination in patients stratified by age group.

Figure 2.

Mean number of tablets taken per month in patients stratified by age group.

Regarding the reason for taking an ED drug, among all age groups high response rates were obtained for sexual satisfaction of themselves and their partners; for instance, positive responses to items such as ‘to restore self‐confidence’, ‘to enhance my sexual ability’, and ‘to enrich my life with my partner’ were made by 80.2, 81.5 and 82.8% of respondents, respectively (Table 1). In patients aged in their 20s and 30s, high response rates were obtained for items such as ‘to restore healthy body condition’ (70.5 and 64.5%, respectively), ‘to avoid breaking up with my partner due to ED’ (65.9 and 61.3%), and ‘for infertility treatment’ (52.3 and 37.6%).

Table 1.

Purpose of taking an erectile dysfunction drug by age group

	Positive response rate (%)
	Age 20s (n = 44)	Age 30s (n = 93)	Age 40s (n = 102)	Age >50 (n = 69)	Total (n = 308)
To satisfy my partner sexually	79.5	88.2	89.2	91.3	88.0
To restore my self‐confidence	77.3	81.7	87.3	81.2	82.8
To satisfy myself sexually	79.5	80.6	84.3	81.2	81.8
To enhance my sexual ability	77.3	82.8	82.4	81.2	81.5
To enrich my life with my partner	75.0	80.6	80.4	82.6	80.2
To receive affection from my partner	75.0	74.2	69.6	62.3	70.1
Not to have a sexless relationship with my partner	63.6	71.0	68.6	73.9	69.8
To enhance feelings of companionship	59.1	61.3	50.0	59.4	56.8
To restore a healthy body condition	70.5	64.5	52.9	40.6	56.2
To avoid breaking up with my partner because of ED	65.9	61.3	48.0	36.2	51.9
For infertility treatment	52.3	37.6	15.7	10.1	26.3

ED, erectile dysfunction.

High positive responses were noted regarding efficacy; those responding that ED drugs were ‘effective’ and ‘generally satisfactory’ accounted for 89.9 and 85.1%, respectively, although slightly lower positive responses to these items were seen among younger patients aged in their 20s (84.1 and 77.3%, respectively). The response rate for ‘no worry about side‐effects’ was also fairly low at 60.1%.

Among 13 items related to problems taking ED drugs, ≥1 item was applicable to 79.5% of the respondents; the mode of the number of responses was three items. Patients who answered ≥3 items accounted for >60%, and there were quite a few patients, particularly among those aged in their 20s and 30s, who answered all 13 items. The highest response rate (48.7%) was noted for ‘I started sexual intercourse assuming that the effect was present, but actually it was not’; the response rate to this item was high in all age groups. In the younger population aged in their 20s and 30s, higher response rates were obtained for ‘I fell asleep earlier while I was waiting for my partner’ (47.7 and 40.9%, respectively) and ‘due to refusal of my partner, I had to give up sexual intercourse for the day’ (47.7 and 45.2%, respectively; Table 2). In patients aged in their 30s, markedly high response rates were obtained for ‘it reached midnight while waiting for a good timing’ (48.4%) and ‘my partner came to the bedroom late because of other distraction’ (46.2%).

Table 2.

Problems encountered when taking an erectile dysfunction drug by age group^†

	Positive response rate (%)
	Age 20s (n = 44)	Age 30s (n = 93)	Age 40s (n = 102)	Age >50 (n = 69)	Total (n = 308)
I started sexual intercourse assuming that the effect was present, but actually it was not	47.7	54.8	45.1	46.4	48.7
Due to the refusal of my partner, I had to give up sexual intercourse for the day	47.7	45.2	37.3	30.4	39.6
I was troubled at meal times, considering that taking food may reduce the effect of the drug	38.6	45.2	36.3	36.2	39.3
The effect of the ED drug had run out by the time of starting sexual intercourse	47.7	40.9	39.2	27.5	38.3
My partner came to the bedroom late because of other distraction	38.6	46.2	27.5	27.5	34.7
My partner fell asleep earlier	38.6	40.9	24.5	31.9	33.1
I had a quarrel with my partner and could not create a suitable atmosphere that night	45.5	40.9	25.5	23.2	32.5
My partner came to the bedroom late because otherwise occupied	40.9	38.7	25.5	24.6	31.5
I fell asleep earlier while I was waiting for my partner	47.7	40.9	18.6	21.7	30.2

^† Items scored positive by >30% of total respondents. ED, erectile dysfunction.

Across all age groups, high response rates were obtained for items related to rigidity and maintenance of erection, such as ‘an erection of sufficient rigidity for penetration can be achieved’ (80.8%), ‘a rigid erection can be obtained’ (80.2%), and ‘after penetration, the erection can be maintained’ (77.9%). However, the response rate for ‘it is troublesome to find a good timing for taking the drug’ tended to be high (66.9%) in these individuals. In patients aged in their 20s and 30s, the response rate tended to be high for ‘I sometimes become impatient, not knowing when the effect will appear after taking the drug’ (61.4 and 64.5%, respectively) and ‘I have a strange sensation that the drug forces me to have an erection’ (59.1 and 60.2%, respectively; Table 3). Positive response rates for items related to experiencing ‘impatience’ and ‘pressure’ tended to be high in patients with a relatively short dosing period lasting <3 months (Table 4). The response rate for ‘it is troublesome to find a good timing for taking the drug’ was highest (74.6%) among patients who had been taking ED drugs for 1–3 months.

Table 3.

Attitudes towards erectile dysfunction drugs by age group^†

	Positive response rate (%)
	Age 20s (n = 44)	Age 30s (n = 93)	Age 40s (n = 102)	Age >50 (n = 69)	Total (n = 308)
An erection of sufficient rigidity for penetration can be achieved	77.3	76.3	85.3	82.6	80.8
A rigid erection can be obtained	79.5	80.6	83.3	75.4	80.2
After penetration, the erection can be maintained	75.0	76.3	78.4	81.2	77.9
It is troublesome to find a good time for taking the drug	63.6	71.0	67.6	62.3	66.9
It is fast acting	70.5	65.6	60.8	58.0	63.0

^† Top five items were extracted.

Table 4.

Attitudes towards erectile dysfunction drugs by duration of dosing (time since starting medication)^†

	Positive response rate (%)
	<1 month	1–3 months	4–6 months	6–12 months	1–2 years	>2 years	Total
An erection of sufficient rigidity for penetration can be achieved	63.6	71.6	85.7	87.0	90.5	87.2	80.8
A rigid erection can be obtained	59.1	77.6	85.7	89.1	88.9	76.9	80.2
After penetration, the erection can be maintained	65.9	73.1	81.6	80.4	92.1	69.2	77.9
It is troublesome to find a good time for taking the drug	68.2	74.6	67.3	69.6	65.1	51.3	66.9
It is fast acting	65.9	65.7	69.4	67.4	61.9	43.6	63.0

^† Top five items were extracted.

In all patients, high response rates were obtained for items such as ‘I want to keep my body and mind young as long as possible’ (89.6%), ‘I have a desire to keep loving someone because being in love is wonderful’ (80.8%), and ‘the ability to perform satisfactory sexual intercourse is proof of good health’ (86.7%). Particularly for the first and third of these items the response rate tended to increase with age. In patients aged in their 20s and 30s, high response rates were obtained for ‘I want to be strict with myself by suppressing desires’ (52.3 and 44.1%, respectively), ‘it is disgraceful for the elderly to have strong sexual desire’ (43.2 and 39.8%, respectively), and ‘I do not want to think about sexual activity because I lost confidence in my sexual ability’ (40.9 and 48.4%, respectively); these response rates were in contrast to the pattern of responses obtained in older patients aged >40 years.

DISCUSSION

WHEN CONDUCTING QUESTIONNAIRE surveys using the Internet, we can generally predict a lower response rate from older‐generation subjects who might be less familiar with online surveys. However, considering that the Internet surveys allow respondents to protect their anonymity, we can expect them to express frank responses. Under these considerations, we believe that the Internet is a suitable method for this type of survey. In this large‐scale questionnaire survey of 50 000 ED patients using the Internet, 308 ED patients who wished to improve their ED symptoms and who had used ED drugs in the past 2 months were extracted to assess their evaluation of ED and its treatment.

Screening conducted in 50 000 patients suggested that 20–30% of respondents aged ≥20 years have experienced ED symptoms, that the ratio is higher in older age groups, and that as many as 60% of patients across all age groups wish to improve their ED symptoms. These results are roughly equivalent to those observed in the USA and Europe. ² , ⁶ However, despite wishing to improve their symptoms many subjects in our study delayed seeking treatment for >1 year after the onset of ED symptoms, particularly older individuals; these results are similar to findings in other countries. Paradoxically, considerable anxiety over having ED as well as the desire for successful treatment and trust of physicians appear widespread among sufferers. ⁷ Previous research has suggested that although younger individuals often do not seek medical treatment because of the belief that their ED symptoms will spontaneously subside, older men resist seeking treatment because they consider that their symptoms are a normal part of aging. ⁸ Across all age groups, however, it seems that the presence of ED symptoms in conjunction with desire for sexual activity are both necessary as predictors of seeking treatment. In the present study, concrete actions taken to improve ED symptoms were not only seeking ED drug therapy and purchasing nutritional supplements and sexual vitalizers, but also searching for information on ED and its treatment (in 10% of patients). This result suggests the importance of the provision of information and enlightenment activities for patients.

At the early stages when subjective symptoms of ED are noted, patients frequently reported ‘irritation and a sense of powerlessness’ in addition to ‘anxiety and a sense of loss’. In particular, it was suggested that there may be a vicious cycle, especially in patients aged in their 30s: awareness of having ED makes them feel physical deterioration and reduction of their presence in both family and at work, leading to reinforcement of a negative self‐image, which further aggravates ED symptoms. A multicountry population‐based study, including Japanese men, has previously confirmed the bidirectional nature of depressive symptoms and ED. ⁹ Therefore, it appears important to offer therapeutic intervention, particularly to younger individuals with such psychological problems.

The ED drugs taken were sildenafil and vardenafil in 65 and 31% of the patients, respectively. As this distribution pattern is similar to the prescription ratio between these two drugs in Japan, the results from the present survey are considered to represent the actual current situation of ED drug users. In the majority of patients aged in their 20s and 30s, the number of tablets prescribed at each medical examination was 3–5; the mean number of tablets taken per month was ≤2. As it appears necessary to take ED drugs continuously to achieve consistent efficacy, an adequate treatment effect might be obtained by increasing the number of tablets per prescription in Japan to 4–8 tablets. This is also more likely to enhance patient satisfaction. A suggested increase in the number of tablets per prescription is considered appropriate based on our findings that patients who used ED drugs for <3 months tended to have ‘impatience’ and ‘pressure’ and that the number of patients who felt it troublesome to find a good time for dosing was highest among those using an ED drug for 1–3 months – suggesting that those with the least experience of taking these medications had the most difficulty associated with their use.

Overall, patients who answered that they had experienced problems in taking ED drugs accounted for approximately 80% of those surveyed. In the younger population, the type and frequency of problems were more notable. The highest response rate was obtained for ‘I started sexual intercourse assuming that the effect was present, but actually it was not.’ Other frequently observed problems were also attributable to difficulty in finding a good time for sexual intercourse relative to the appearance of the effect of the drugs.

Erectile dysfunction drugs were highly evaluated in terms of their pharmacological action, such as ‘a rigid erection can be obtained’ and ‘after penetration, the erection can be maintained’. This result is in line with our previous data on patient expectation: ‘more rigid penile erection can be obtained and maintained’ was a functional aspect in an attitude survey of ‘a better sex life’ that we conducted in 3193 men in 2005. ⁵ In contrast, negative assessments such as ‘timing for dosing’, ‘timing of the appearance of effect’, and ‘a strange sensation that the drug forces me to have an erection’ were reported by many users. Moreover, a survey conducted in 300 married couples in Japan reported that ‘the timing for starting sexual activity is unforeseeable before more than 30 minutes’ in ≥80% of men and women. ¹⁰ Thus, although largely satisfied regarding the erection induced by ED drugs, many users appear troubled by finding a good time for dosing for sexual intercourse, or appear to feel that it is unnatural.

In Japan, tadalafil was clinically introduced as the third available ED drug in 2007. Tadalafil is characterized by producing a longer‐lasting action that allows for more spontaneity in sexual activity than conventional ED drugs. ¹¹ , ¹² Indeed, randomized evidence has consistently suggested that patients exhibit significantly higher preferences for using tadalafil over sildenafil, regardless of age and severity of ED. ¹³ , ¹⁴ , ¹⁵ , ¹⁶ However, because direct head‐to‐head comparisons have not been made, there are no data on differences in the efficacy and safety among the available ED drugs. The present survey was implemented before the launch of tadalafil; therefore, with regard to problems in taking ED drugs and negative assessments, problems related to finding a good time for dosing relative to the appearance of the effect and related to a lack of spontaneity in their use may become irrelevant with the spread of long‐acting tadalafil among users. The use of an ED drug that causes no difficulties or problems in finding a good time for dosing before sexual intercourse is expected not only to improve the self‐image of men who have started to notice ED, leading to activation and fulfillment of their lives as a whole, but also to enhance the satisfaction and security of their partners.

Appendix I

Survey form

Questionnaire about erectile dysfunction drugs.

In this survey, the following symptoms are referred to as erectile dysfunction (ED):

‘Concern about penile rigidity and maintenance of erection’

‘Occasional difficulty with penetration due to insufficient rigidity of erection during sexual intercourse’

‘Occasional difficulty in maintaining an erection during sexual intercourse’

Q1: When did you become aware of ‘ED’? [Input required]

• 1Up to 3 months since the awareness of ED
• 2Between 3 and 6 months since the awareness of ED
• 3Between 6 months and 1 year since the awareness of ED
• 4Between 1 year and 2 years since the awareness of ED
• 5Between 2 and 3 years since the awareness of ED
• 6More than 3 years since the awareness of ED

Q2: When did you start taking an ED drug? [Input required]

• 1Up to 1 month after becoming aware of ED
• 2Between 1 month and 3 months after becoming aware of ED
• 3Between 3 and 6 months after becoming aware of ED
• 4Between 6 months and 1 year after becoming aware of ED
• 5Between 1 year and 2 years after becoming aware of ED
• 6More than 2 years after becoming aware of ED

Q3: What ED drug is prescribed by your doctor?

*If more than 1 drug is taken, please answer for the ED drug mainly taken.

[Input required]

• 1Viagra
• 2Levitra
• 3Other
• 4Unknown

Q4: How many tablets of your main ED drug (the drug selected in Q3) have you taken on average per month for the past 6 months?

*If 1 tablet is taken in 2 months on average, enter ‘0.5’.

[Input required]

Q5: How many tablets of your main ED drug (the drug selected in Q3) are prescribed for you at each medical examination? [Input required]

Q6: Please answer regarding the reasons why you are taking an ED drug. To what extent do the following items apply to you? For each item, select the item (1 to 7 in the box below) that is most applicable to you.

*If you have a reason other than items 1 to 11, please describe it in the free‐entry column under ‘12. Other’.

[Input required, except for ‘Other’]

• 1To restore self‐confidence
• 2To satisfy myself sexually
• 3To enhance my sexual ability
• 4To enrich my life with my partner
• 5To receive affection from my partner
• 6To satisfy my partner sexually
• 7To avoid breaking up with my partner due to ED
• 8Not to have a sexless relationship with my partner
• 9For infertility treatment
• 10To enhance feelings of companionship
• 11To restore a healthy body condition
• 12Other

Q7: Please answer regarding your main ED drug (the drug selected in Q3). For each item, select the item (1 to 7 in the box below) that is most applicable to you. [Input required]

• 1Effective
• 2No worry about side‐effects
• 3Generally satisfactory

Q8: Have you ever experienced the following conditions after taking your main ED drug (the drug selected in Q3) before sexual intercourse? Please answer based on your experience. [Input required]

• 1My partner fell asleep earlier
• 2I fell asleep while I was waiting for my partner
• 3My partner came to the bedroom late because otherwise occupied
• 4I had a quarrel with my partner and could not create a suitable atmosphere that night
• 5My child (children) did not go to bed readily
• 6I started sexual intercourse assuming that the effect was present, but actually it was not
• 7I was embarrassed to take the drug in front of my partner
• 8My partner came to the bedroom late because otherwise distracted
• 9It reached midnight while waiting for a good timing
• 10I was troubled at meal times, considering that taking food may reduce the effect of the drug
• 11I had an urgent work call
• 12Due to refusal of my partner, I had to give up sexual intercourse for the day
• 13The effect of the ED drug had run out by the time of starting sexual intercourse

Q9: Please describe any other problems you experienced after taking your main ED drug (the drug selected in Q3) based on your experience. Please provide as many as you can recall.

Q10: Please answer regarding your main ED drug (the drug selected in Q3). For each item, select the response (1 to 7 in the box below) most applicable to you. [Input required]

• 1I sometimes become impatient, not knowing when the effect will appear after taking the drug
• 2I sometimes become impatient, feeling the need to complete sexual intercourse before the effect runs out
• 3It is troublesome to find a good timing for taking the drug
• 4I sometimes feel pressure to initiate sexual intercourse after taking the drug
• 5I feel it is unnatural to plan performance of sexual activities
• 6I have a strange sensation that the drug forces me to have an erection
• 7I am reluctant to take the drug in front of my partner
• 8An erection of sufficient rigidity for penetration can be achieved
• 9The drug is unlikely to cause side effects
• 10The drug action is unaffected by meals
• 11It is fast acting
• 12A rigid erection can be obtained
• 13After penetration, the erection can be maintained

Q11: Can you find a good timing for sexual intercourse? If yes, how long before sexual intercourse can you find a good timing? [Input required]

• 1I cannot find a good timing
• 2Up to 30 minutes before sexual intercourse
• 3Between 30 minutes and 1 hour before sexual intercourse
• 4Between 1 hour and 3 hours before sexual intercourse
• 5Between 3 and 6 hours before sexual intercourse
• 6Between 6 and 12 hours before sexual intercourse
• 7More than 12 hours before sexual intercourse

Q12: For each item, select the response (1 to 7 in the box below) most applicable to you. [Input required]

• 1I would like to cherish a natural timing for sexual activity with my partner, even when an ED drug is used
• 2I think it is unnatural to plan for sexual intercourse by using an ED drug
• 3I would like to be spontaneous in sexual activity, even when an ED drug is used

Q13: Please recall when you started to feel ED symptoms. To what extent do the following apply to the feelings you had when you became aware of having ED? [Input required]

• 1Irritation and a sense of powerlessness regarding the inability to satisfy my partner
• 2Anxiety that I may be disliked by or separated from my partner
• 3Anxiety and a sense of loss that I have physically deteriorated considerably
• 4Anxiety about maintaining dignity as a husband or father in the family
• 5Anxiety that I may be left behind by my colleagues and juniors at work
• 6Loss of self‐confidence in many aspects of daily living (loss of confidence)
• 7A sense of loss of purpose in life, being incapable of maintaining a good self‐image
• 8I started to have anxiety about my future health status
• 9Non‐specific anxiety about my future was increased

Q14: Please describe any other feelings you had when you became aware of having ED. Please provide as many details as you can recall.

Q15: Please answer regarding ‘your lifestyle’, ‘what you care about in your daily living’, ‘sexual life’, etc. To what extent are the following matters applicable to you? [Input required]

• 1I want to keep my body and mind young for as long as possible
• 2I care about public order and standards of decency and also to maintain social order
• 3I want to be strict with myself by suppressing desires
• 4I tend to get carried away with praise
• 5Authorities should be obeyed and respected
• 6I have a desire to keep loving someone because being in love is wonderful
• 7Men should focus on work, and women should focus on raising a family
• 8It is a symbol of manhood to satisfy his partner during sexual intercourse
• 9I accept age‐related decrease in sexual ability because it is natural
• 10The ability to perform satisfactory sexual intercourse is proof of good health
• 11It is disgraceful for the elderly to have strong sexual desires
• 12I desire to have sexual relationships with many partners
• 13Ordinary sexual intercourse is enough for me; I don't expect anything special
• 14I don't want to think about sexual activity because I lost confidence in my sexual ability
• 15I don't care if someone visits a sex shop even though he has a partner