Abstract
Introduction.
Western cultural perceptions that favor spontaneous sex may create unrealistic expectations for erectile dysfunction (ED) treatment. Little is known about how users of phosphodiesterase type 5 inhibitors (PDE5Is) plan sexual activity and timing of their preactivity PDE5I ingestion. Because various PDE5Is vary in their duration of action and dosage regimen, this may be an important consideration in selecting the optimal agent for the ED patient.
Aim.
To better understand the sexual habits of PDE5I users
Methods.
Men from 7 countries (Brazil, China, Italy, Japan, Russia, Taiwan, Turkey) were screened online for age, self-reported comorbidities, and ED medication use in the prior 3 months. After screening, eligible participants were asked to complete a 7-question, self-administered, online survey containing questions regarding sexual habits and behaviors.
Main Outcome Measures.
Survey questions focused primarily on advanced planning of sexual intercourse and timing of PDE5I ingestion but also addressed the frequency of sexual intercourse and ED medication use.
Results.
Of the 1458 respondents (response rate: 48%; median age: 48 years [interquartile range (IQR), 44–55]), 83% always/sometimes planned a specific time for intercourse in advance; 72% planned a specific time for sexual intercourse up to several hours in advance. Of respondents who planned in advance, more than half planned specific days of the week (55%) and times of the day (60%) for sexual intercourse. The time to sexual intercourse after dosing was ≤1 hour for 70% and ≤4 hours for 96% of men. The median frequency of sexual intercourse was 6 times/month (IQR, 4–10), with ED medication taken a median of 5 times/month (IQR, 3–8).
Conclusions.
Sexual activity is usually planned by ED medication users several hours in advance, and the vast majority are attempting activity within a short time after ingestion of the agent. These data should aid clinicians in the selection of the optimal PDE5I.
Keywords: sexual habits, erectile dysfunction, phosphodiesterase type 5 inhibitors, treatment satisfaction, online survey
Introduction
Erectile dysfunction (ED) is defined as the persistent inability to achieve or maintain an erection sufficient for satisfactory sexual performance [1]. ED is a highly prevalent condition; approximately 50% of men aged 40 to 70 years reported ED in the Massachusetts Male Aging Study, with the severity of ED increasing with increasing age [2]. In men aged 40 to 70 years in Brazil, Italy, Japan, and Malaysia, the age-standardized prevalence of mild, moderate, or severe ED ranged from approximately 40% to 80% [3]. In addition to age, ED is significantly associated with other diseases, including cardiovascular disease, hypertension, diabetes, depression, and lower urinary tract symptoms [2,4,5].
Erectile dysfunction can have a negative impact on overall quality of life and well-being, sexual relationships, and the partner relationship [5,6]. Several oral phosphodiesterase type 5 inhibitors (PDE5Is) are available, each with different attributes. PDE5Is are a first-line therapy for the treatment of ED [7–9]. Within Western culture, spontaneous sex is portrayed as the most gratifying type of sex, which may promote unrealistic expectations in patients with ED [10]. Patient satisfaction with ED treatment may be optimized by the choice of PDE5I based on that patient’s sexual habits. Despite the availability of several guidelines and the volume of literature on ED and PDE5I use, the sexual habits of men with ED are not integrated into the management of ED, with limited information available on the sexual habits and behaviors of men taking a PDE5I, especially in non-Western countries.
Aims
The objective was to evaluate the sexual habits and behaviors of men taking PDE5I, including aspects of advanced planning and satisfaction with the medication.
Methods
Subjects in 7 countries (Brazil, China, Italy, Japan, Russia, Taiwan, and Turkey) who were already enrolled as potential survey respondents in an Ipsos Healthcare (London, UK; independent market research company) database were invited to participate in an online survey conducted from October 7 to November 2, 2015. Multiple methods were used to screen for respondents, including using panels of ED sufferers who previously agreed to participate in market research. Local companies contracted by Ipsos Healthcare distributed emails to their sample panels that contained a weblink to learn more and answer the qualifying questions. Potential participants were informed of the sensitive nature of the survey questions, that they could withdraw at any time during the online survey, and that their responses to the survey questions would remain anonymous and confidential. Potential participants were screened online for male gender, age 40 to 70 years (except 35–65 years in Russia and 30–70 years in Brazil), use of a PDE5I in the past 3 months, and comorbidities. PDE5I taken included sildenafil citrate (branded and generic), tadalafil (on demand and once daily; branded and generic), and vardenafil (branded). Subjects who met the screening survey eligibility criteria were asked to complete a self-administered online survey (see Appendix). Nominal compensation was offered for respondents to complete the survey and varied by country.
Main Outcome Measures
The main outcome measures were survey questions on the frequency of advanced planning of sexual intercourse, timing of PDE5I ingestion, the frequency of sexual intercourse per month, and the frequency of ED medication use per month. Descriptive results are reported.
Results
Respondents
Overall, 230,610 men received the initial invitation and 19,250 (8%) responded. Of those who responded, 3029 men met the survey eligibility criteria and 1458 (48%) of eligible participants went on to complete the 8-question, self-administered, online survey (completion time: ~10 minutes). The median age of the total population of 1458 ED medication users was 48 years (interquartile range [IQR]: 44–55 years; mean [SD]: 50.0 [7.5] years; Table 1). The percentages of respondents according to age subgroups for the total population and for each individual country are shown in Table 1. The largest age subgroup in 6 of the 7 countries was 41 to 50 years; in Japan, 51 to 60 years was the largest age subgroup. In the total population of 1458 men, 36% self-reported the presence of high blood pressure, 30% reported high cholesterol, 26% reported prostate problems, 22% reported depression, and 19% reported diabetes. Comorbidities reported by age subgroup are shown in Table 2. The ED medications respondents reported taking (screening questions) included generic and branded sildenafil citrate, generic and branded tadalafil, and branded vardenafil. Medication selection was based on the options available in each country at the time of the survey. Overall, 35% reported that the PDE5I last used was sildenafil (branded); 28% reported tadalafil (branded), and the remainder was distributed among the other agents used. Most participants (51%) had used only 1 type of PDE5I in the previous 3 months; 28% had used 2, and 15% had used 3 PDE5Is. Six percent had used ≥4 PDE5I agents. These values were similar by age subgroup, with the exception that 10% of respondents aged 30 to 40 years reported taking ≥4 PDE5Is in the previous 3 months (Table 2).
Table 1.
Age and Comorbidities of Survey Respondents
| Total (N=145) |
Brazil (n=252) |
China (n=254) |
Taiwan (n=100) |
Italy (n=251) |
Japan (n=250) |
Russia (n=251) |
Turkey (n=100) |
|
|---|---|---|---|---|---|---|---|---|
| Age, y | ||||||||
| Mean (SD) | 50.0 (7.5) | 53.0 (8.5) | 48.7 (5.4) | 48.2 (6.2) | 49.9 (7.3) | 54.1 (8.0) | 46.6 (5.9) | 45.8 (5.7) |
| Median (IQR) | 48.0 (44–55) | 52.0 (46–59) | 48.0 (45–52) | 47.0 (44–52) | 48.0 (44–54) | 54.0 (48–60) | 45.0 (42–51) | 44.0 (41–48) |
| Age subgroups, n (%) | ||||||||
| 30–40 y | 78 (5) | 9 (4) | 3 (1) | 8 (8) | 11 (4) | 7 (3) | 27 (11) | 13 (13) |
| 41–50 y | 787 (54) | 110 (44) | 165 (65) | 64 (64) | 138 (55) | 83 (33) | 157 (63) | 70 (70) |
| 51–60 y | 446 (31) | 86 (34) | 81 (32) | 23 (23) | 77 (31) | 102 (41) | 62 (25) | 15 (15) |
| 61–70 y | 147 (10) | 47 (19) | 5 (2) | 5 (5) | 25 (10) | 58 (23) | 5 (2) | 2 (2) |
| Comorbidities, n (%) | ||||||||
| High blood pressure | 523 (36) | 90 (36) | 67 (26) | 63 (63) | 97 (39) | 60 (24) | 116 (46) | 30 (30) |
| High cholesterol | 432 (30) | 87 (35) | 53 (21) | 48 (48) | 100 (40) | 52 (21) | 67 (27) | 25 (25) |
| Prostate problems | 386 (26) | 47 (19) | 110 (43) | 25 (25) | 78 (31) | 32 (13) | 76 (30) | 18 (18) |
| Depression | 319 (22) | 63 (25) | 26 (10) | 17 (17) | 59 (24) | 30 (12) | 85 (34) | 39 (39) |
| Diabetes | 276 (19) | 66 (26) | 47 (19) | 30 (30) | 44 (18) | 35 (14) | 31 (12) | 23 (23) |
Table 2.
Results by Age Subgroup
| Total (N=1458) |
30–40 y (n=78) |
41–50 y (n=787) |
51–60 y (n=446) |
61–70 y (n=147) |
|
|---|---|---|---|---|---|
| Comorbidities, n (%) | |||||
| High blood pressure | 523 (36) | 30 (38) | 253 (32) | 167 (37) | 73 (50) |
| High cholesterol | 432 (30) | 30 (38) | 220 (28) | 134 (30) | 48 (33) |
| Prostate problems | 386 (26) | 26 (33) | 209 (27) | 106 (24) | 45 (31) |
| Depression | 319 (22) | 23 (29) | 185 (24) | 81 (18) | 30 (20) |
| Diabetes | 276 (19) | 15 (19) | 148 (19) | 74 (17) | 39 (27) |
| PDE5Is taken in the previous 3 months, n (%) | |||||
| 1 | 747 (51) | 41 (53) | 392 (50) | 241 (54) | 73 (50) |
| 2 | 401 (28) | 18 (23) | 227 (29) | 120 (27) | 36 (24) |
| 3 | 219 (15) | 11 (14) | 117 (15) | 59 (13) | 32 (22) |
| ≥4 | 91 (6) | 8 (10) | 51 (6) | 26 (6) | 6 (4) |
| Planned sexual intercourse in advance | |||||
| Always | 366 (25) | 14 (18) | 191 (24) | 127 (28) | 34 (23) |
| Sometimes | 844 (58) | 53 (68) | 474 (60) | 240 (54) | 77 (52) |
| Hardly ever | 181 (12) | 9 (12) | 89 (11) | 62 (14) | 21 (14) |
| Never | 51 (3) | 2 (3) | 23 (3) | 14 (3) | 12 (8) |
| Don’t know | 9 (1) | 0 (0) | 5 (1) | 2 (<1) | 2 (1) |
| Prefer not to say | 7 (<1) | 0 (0) | 5 (1) | 1 (<1) | 1 (1) |
| Timing of advanced planning of sexual intercourse, n (%) | N=1391 | n=76 | n=754 | n=429 | n=132 |
| Up to 1 h in advance | 367 (26) | 18 (24) | 219 (29) | 105 (24) | 25 (19) |
| Up to several h in advance | 630 (45) | 37 (49) | 351 (47) | 191 (45) | 51 (39) |
| Up to 1 d in advance | 274 (20) | 14 (18) | 140 (19) | 86 (20) | 34 (26) |
| Up to 1 wk in advance | 67 (5) | 4 (5) | 26 (3) | 26 (6) | 11 (8) |
| More than 1 wk | 24 (2) | 1 (1) | 4 (1) | 15 (3) | 4 (3) |
| Don’t know | 25 (2) | 1 (1) | 14 (2) | 5 (1) | 5 (4) |
| Prefer not to say | 4 (<1) | 1 (1) | 0 (0) | 1 (<1) | 2 (2) |
| Agreement with sexual planning statements, n (%) | N=1391 | n=76 | n=754 | n=429 | n=132 |
| I plan when I am going to have sexual intercourse | |||||
| Strongly agree | 415 (30) | 16 (21) | 229 (30) | 121 (28) | 49 (37) |
| Tend to agree | 605 (43) | 42 (55) | 311 (41) | 201 (47) | 51 (39) |
| There are specific days of the week when I plan to have sexual intercourse | |||||
| Strongly agree | 276 (20) | 13 (17) | 149 (20) | 86 (20) | 28 (21) |
| Tend to agree | 484 (35) | 28 (37) | 263 (35) | 144 (34) | 49 (37) |
| There are specific times of day when I plan to have sexual intercourse | |||||
| Strongly agree | 329 (24) | 13 (17) | 169 (22) | 102 (24) | 45 (34) |
| Tend to agree | 502 (36) | 36 (47) | 253 (34) | 170 (40) | 43 (33) |
| Time to sex, n (%) | |||||
| ≤30 min | 285 (20) | 22 (28) | 169 (21) | 76 (17) | 18 (12) |
| 30 min to 1 h | 729 (50) | 37 (47) | 404 (51) | 230 (52) | 58 (39) |
| 1–4 h | 381 (26) | 16 (21) | 184 (23) | 125 (28) | 56 (38) |
| 4–8 h | 36 (2) | 2 (3) | 17 (2) | 10 (2) | 7 (5) |
| 8–12 h | 12 (1) | 0 (0) | 8 (1) | 2 (<1) | 2 (1) |
| >12 h | 2 (<1) | 1 (1) | 0 (0) | 1 (<1) | 0 (0) |
PDE5I=phosphodiesterase type 5 inhibitor.
Sexual Habits Survey
Of the 1458 men who reported taking ED medication, 83% reported that they always or sometimes planned for sexual intercourse in advance (Figure 1). There was reasonable concordance in this regard between countries, although these rates varied from 73% in Japan to 95% in China. Similarly, most respondents in any age subgroup reported always or sometimes planning intercourse in advance (Table 2).
Figure 1.
Planning sexual intercourse. Net percentage may not equal sum of percentages indicated in bar because of rounding.
Of those planning sexual activity in advance, 72% planned sexual intercourse up to several hours in advance (Figure 2). There was significant variability in this factor between countries, with planning up to several hours in advance reported by 39% of respondents from Japan and 81% in Russia, with Japan being the only country where a notable proportion of respondents planned more than 1 week in advance. Furthermore, of the respondents who indicated that they planned in advance, many planned specific days of the week (55%) and times of the day (60%) for sexual intercourse (Figure 3). Among age subgroups, nearly half of those aged 30 to 60 years planned sexual intercourse up to several hours in advance, whereas 39% of those aged 61 to 70 years did so. Similar to the total population, most respondents reported planning for specific days of the week and times of the day (Table 2).
Figure 2.
Timing of advance planning of sexual intercourse. Net percentage may not equal sum of percentages indicated in bar because of rounding.
Figure 3.
Planning of sexual intercourse for specific occasions. Net percentage may not equal sum of percentages indicated in bar because of rounding.
Thirty percent of ED medication users strongly agreed with the statement, “I plan when I am going to have sexual intercourse.” Among men using generic or branded tadalafil, branded vardenafil, or generic sildenafil, no statistically significant differences were observed for percentages that strongly agreed with this statement (mean, 30%). Only 2% to 3% of men strongly disagreed with the statement no matter which PDE5I was last used.
In the total population of 1458 men, the time to sexual activity commencement after ED medication dosing was ≤30 minutes for 20%, 30 to 60 minutes for 50%, and 1 to 4 hours for 26%, with 96% or more of all respondents in all countries having sexual activity within 4 hours of using the PDE5I (Figure 4). Interestingly, the use of a PDE5I within 30 minutes of sexual activity ranged from 8% in Japan to 32% in Taiwan. The majority of respondents in any age subgroup reported time to sexual activity as 1 hour or less.
Figure 4.
Time to sexual intercourse after ED medication dosing. Net percentage may not equal sum of percentages indicated in bar because of rounding. ED=erectile dysfunction.
The median frequency of sexual intercourse was 6 times/month (IQR, 4–10) for the total population, ranging from 3 times/month (IQR, 2–5) in Japan to 8 times/month in Russia (IQR, 5–10) and Turkey (IQR, 4–10). ED medication was taken a median of 5 times/month (IQR, 3–8), ranging from 2.5 times/month (IQR, 2–4)in Japan to 6 times/month in Italy and Russia (IQR, 4–10; Figure 5). Median frequency of sexual intercourse was 6 times/month (IQR, 4–10) for those aged 30 to 50 years and 4 times/month (IQR, 3–8) for those 51 to 70 years of age.
Figure 5.
Frequency of sexual intercourse and ED medication use per month. ED=erectile dysfunction.
Only 22% of respondents reported being very satisfied with the ED medication that they had last used, and 63% were fairly satisfied; similar percentages were reported by age subgroup (17%–24% very satisfied, 59%–64% fairly satisfied).
Discussion
The primary objective of the current study was to better understand the sexual habits, behaviors, and treatment satisfaction of men who reported taking PDE5Is in the previous 3 months. The online survey was conducted by an independent market research organization in accordance with the requirements of the international quality standard for market research set forth by the European Pharmaceutical Market Research Association and the European Society for Opinion and Marketing Research. The respondents were not aware of the survey sponsor, and all identifying information was de-identified to maintain confidentiality. The countries included were selected based on the high use of PDE5Is, with sample size targets determined by balancing the desired size for robust analysis with the likelihood of finding qualified respondents. Candidate sampling was performed by local sample panel companies who contacted potential respondents with an email containing a link to the survey. For the men from 7 countries who reported taking a PDE5I in the past 3 months, the survey response rate (48%) was good and comparable to that of a recent internet-based survey of male sexuality [11]. For Russia and Brazil, lower age ranges were applied based on feedback from local opinion leaders that ED tends to emerge at a younger age in these countries. Patient comorbidity profiles were similar to those seen in the general ED population [12–14], suggesting that the respondents were representative of this population and supporting extrapolation of these findings to most patients with ED.
The frequency of sexual intercourse reported for the overall population in the current survey (median: 6 times/month; range 4–8 times/month; mean: 7 times/month) is similar to that reported in previous studies [15–18]. The reasons for differences between countries in this regard were not investigated, but is a topic worthy of further exploration.
The key messages from the data are that the respondents often planned sexual activity in advance, with 83% planning in advance at least sometimes; the majority plan to have sex up to several hours in advance; and nearly all ED medication users were having sexual activity within 4 hours of ingesting their PDE5I. Thus, these data challenge the concept of spontaneity; the majority of people appear to be having sex in a highly planned fashion. In this regard, these planning data are in contrast to a study by Eardley et al., which showed in an internet survey that the median time frame from thinking about sex to having sexual activity was 30 and 31 minutes (mean time frame: 53 and 54 minutes) for men with ED and those without ED, respectively, with the time frame decreasing with increasing age [19]. This difference could be explained by cultural factors. The fact that nearly all men were having sex within 4 hours of using their PDE5I is of clinical importance. Clinicians should now consider discussing sexual dynamics with patients to define their sexual patterns and behaviors in an effort to select the optimal PDE5I for that particular patient.
Another interesting finding from this survey is the proportion of PDE5I users ingesting the medication within 30 minutes of sexual activity, which is in stark contrast to the labeling of the agents. This might reflect the failure of prescribing clinicians to advise patients how to use the medications correctly or may indicate that patients were receiving the medication through nonmedical sources (it is not known whether participants were taking PDE5Is that were prescribed or purchased over the internet).
Of note, the PDE5Is used in this study included sildenafil (branded and generic), tadalafil (branded and generic, on demand and once a day), and vardenafil (branded). The major players were therefore included, but the study design excluded other agents used less frequently in the participating countries such as mirodenafil, lodenafil, avanafil, and udenafil, although it is unlikely that patient use of these agents would have differed.
Limitations of the survey include the fact that some respondents (from Russia and Brazil) were younger than the general ED patient; the inability to confirm diagnosed ED (only the use of a PDE5I was known); and the reliance on self-reporting of comorbidity data rather than medical record review. However, the survey was answered by a large group of men, all using PDE5Is within the past 3 months and thus likely meeting the definition of ED, with a broad range of comorbidities. Finally, because no such survey results have been published in the literature to date, these data should provide insight into the mindset of the patient using a PDE5I and should aid clinicians in decision making regarding PDE5I selection.
Conclusions
For the population assessed in this study, most ED medication users plan sexual intercourse ahead of the encounter, most up to several hours in advance, and nearly all take their PDE5I within a few hours of sexual activity. In clinical practice, a thorough understanding of patients’ sexual habits, behaviors, and treatment goals can aid healthcare providers in the selection of the optimal ED medication for each patient.
What’s known?
Patient satisfaction with erectile dysfunction treatment could be optimized by using an oral phosphodiesterase type 5 inhibitor (PDE5I) with attributes that best suit a patient’s sexual habits.
Little is known regarding the sexual habits and behaviors of men taking PDE5Is.
What’s new?
This 7-country survey demonstrated that men taking a PDE5I typically plan sexual activity several hours in advance.
Despite their planning efforts, most PDE5I users attempted sexual activity within a short time after ingestion of the agent.
Acknowledgments
This study was sponsored by Pfizer Inc. Ipsos Healthcare received funding from Pfizer for the development of study materials, managing fieldwork and data processing, recruiting respondents, and preparing analyses. Editorial and medical writing assistance was provided by Patricia B. Leinen, PhD, and Jill E. Kolesar, PhD, of Complete Healthcare Communications, LLC, and funded by Pfizer Inc.
Appendix
SURVEY QUESTIONS
Q1. How many times do you have sexual intercourse in a typical month? Please enter the number of times in a typical month.
Q2. How long after taking [erectile dysfunction medication] before you typically have sexual intercourse? Please select one:
| 30 minutes or less |
| Over 30 minutes up to 1 hour |
| Over 1 hour up to 4 hours |
| Over 4 hours up to 8 hours |
| Over 8 hours to up to 12 hours |
| 12 hours or more |
| Prefer not to say |
| Don’t know |
Q3. In a typical month, on how many days do you take [erectile dysfunction medication]? Please enter the number of times in a typical month.
Q4. Typically before you have sexual intercourse, how often do you plan a specific time in advance? Please select one:
| Always |
| Sometimes |
| Hardly ever |
| Never |
| Prefer not to say |
| Don’t know |
Q5. FOR RESPONDENTS WHO ANSWER ALWAYS/SOMETIMES/HARDLY EVER AT Q4: When you do plan a time for sexual intercourse, how far in advance do you typically plan ahead? Please select one:
| Up to one hour in advance |
| Up to several hours in advance |
| Up to one day in advance |
| Up to one week in advance |
| More than one week in advance |
| Prefer not to say |
| Don’t know |
Q6. FOR RESPONDENTS WHO ANSWER ALWAYS/SOMETIMES/HARDLY EVER AT Q4: To what extent do you agree or disagree with the following statements?
| I plan when I am going to have sexual intercourse |
| There are specific days of the week I plan on having sexual intercourse |
| There are specific times of the day I plan on having sexual intercourse |
Q7. How satisfied are you with [insert answer to screening question of which ED medication was taken most recently]?
| Very satisfied |
| Fairly satisfied |
| Neither satisfied nor dissatisfied |
| Fairly dissatisfied |
| Very dissatisfied |
| Don’t know |
Footnotes
Disclosures
John Mulhall: Consultant for Pfizer, Lilly, Absorption Pharma
Tarek Hassan: Employee of Pfizer Inc
James Rienow: Former employee of Pfizer Ltd during the conduct of the study and initiation of the manuscript
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