Weaker Masturbatory Erection May Be a Sign of Early Cardiovascular Risk Associated with Erectile Dysfunction in Young Men Without Sexual Intercourse
Yan-Ping Huang MD, PhD; Bin Chen MD, PhD; Feng-Juan Yao MD; Sheng-Fu Chen MD; Bin Ouyang MD; Chun-Hua Deng MD, PhD; and Yi-Ran Huang MD, PhD
ONLINE: March 3, 2014– The Journal of Sexual Medicine
Erectile dysfunction (ED) is associated both with aging and with conditions related to aging, such as diabetes, hypertension, cardiovascular disease (CVD), and obesity.
ED does occur in younger men. However, unlike older men, the etiology of ED in this group has not been widely studied.
Some young men have weaker masturbatory erections with no sexual intercourse (WME-NS). Many professionals believe ED in younger men is psychogenic and do not investigate other risk factors.
This study aimed to determine whether underlying risk factors exist in men with WME-NS and whether such risk factors are similar to those of men with identified ED.
Participants and Methods
Prospective study participants between the ages of 18 and 40 were evaluated for general health status, sexual history, physical examination, blood chemistry and endocrine assay, and cardiovascular risk factors. Men were excluded if they had severe diseases (such as coronary artery disease or congestive heart failure), penile deformities, pelvic surgery, or long-term pharmacotherapy or addiction problems. Men with hypertension and diabetes were also excluded.
The ED population consisted of men who had had ED for at least six months. Non-ED subjects were selected from infertility patients and healthy men without erection problems. To be included in the study, men in both groups were required to be in a stable relationship with a female partner and to have had one occurrence of sexual intercourse during the previous four weeks. They were also required to have a masturbation history of at least one year and to masturbate at least once monthly. They must have experienced weaker masturbatory erections for at least six months.
Evaluation and Classification of Erectile Dysfunction
The ED and non-ED groups were assessed with the five-item International Index of Erectile Function (IIEF-5). Men with scores of 5 ≤ IIEF-5 ≥ 21 were classified as having ED. Those with scores greater than 22 were classified as not having ED.
Men without partners or sexual intercourse were evaluated by their masturbatory erections, which were considered weak if they met one of the following criteria:
1. Poor erectile response to audio visual sexual stimulation and/or sexual fantasy;
2. Weak penile hardness during the course of masturbation
3. Low satisfaction to the course of masturbation
Men who had had weak masturbatory erections for at least six months were classified as having WME-NS.
Nocturnal Penile Tumescence and Rigidity (NPTR) Test
All men used the NPTR test at home to provide data on “natural” nocturnal erections over the course of one to three nights with eight hours of sleep.
Patients who did not meet any of the following criteria were classified as having an NPTR abnormality:
1. More than three full erections during the night;
2. Greater than 70% of maximal tip rigidity;
3. Greater than 15 minutes of average duration of erectile events;
4. Greater than 60 minutes of total duration in erectile events.
Assessment of Vascular Parameters
The researchers used the Cardiovascular Ultrasound System to assess the vascular and hemodynamic status of the brachial artery and bilateral carotid for each man.
For this study, carotid intima-media thickness (CIMT) of greater than 0.80 mm was defined as subclinical atherosclerosis.
Brachial artery flow-mediated dilation (FMD) was used to assess vascular endothelial function. An FMD reading of less than 10 indicated endothelial dysfunction. Readings of 10 and above indicated normal endothelial function.
Measurement of Target Biochemical Indicators
Blood was drawn from each man and analyzed for a variety of biochemical indicators, including uric acid, sex hormones, creatinine, lipids, insulin, and glycosylated serum protein (GSP).
Overall, 78 WME-NS cases, 179 ED cases, and 43 non-ED cases were screened for analysis. All men were between the ages of 18 and 40.
For the ED group, the top four ED risk factors were:
• endothelial dysfunction (73.2%)
• high level GSP (47.5%)
• insulin resistance (46.9%)
• NPTR abnormality (40.8%)
For the WME-NS group, the top four ED risk factors were:
• endothelial dysfunction (62.8%)
• insulin resistance (50.0%)
• high level GSP (41.0%)
• NPTR abnormality (33.3%)
Age-adjusted models of logistic regression analyses showed that endothelial dysfunction, NPTR abnormality, and high level GSP were associated with both ED and WME-NS. The multivariate logistic regression model showed that endothelial dysfunction, NPTR abnormality, and high level GSP were the independent risk factors for ED. Endothelial dysfunction was the independent risk factor for WME-NS.
These results showed that men with WME-NS had similar underlying risk factors as those with ED, including subclinical vascular dysfunction, abnormal nocturnal tumescence, and early glycometabolic disorder.
Based on their analysis, the authors suggested that both ED and WME could be considered as early cardiovascular risk factors in young men.
ED in older men is usually attributed to hormonal and penile structural processes as well as comorbidities associated with aging. Usually, such diseases are advanced and have caused vascular damage.
While younger men may not have the same degree of comorbidities, the subclinical disorders (vascular dysfunction, abnormal nocturnal tumescence and early glycometabolic disorder) can still occur and may be used to predict ED in this age group.
Currently, there are no recommendations for healthcare professionals who must assess young men with non-typical ED. Examples of non-typical ED include honeymoon ED (with a first sexual attempt), teenager ED, mild ED, unrecognized ED, and WME-NS. These types of ED cannot be assessed with the IIEF and are usually believed to be psychogenic.
However, past studies have shown that early vascular dysfunction and cardiovascular risk factors have occurred with some forms of non-typical ED. In addition, the present study shows similar risk factors in WME-NS.
Thus, it’s possible that WME-NS is a sign of early cardiovascular risk associated with ED.
The authors acknowledged some limitations. Their study sample was small. However, they still considered the results valuable. Also, the researchers did not use Duplex ultrasound (DUS) data. But DUS has been deemed unreliable in younger men with early onset ED, they said.
The authors concluded that “underlying risk associated with erectile dysfunction also occur in young men presenting weaker erection with no sexual intercourse, despite this cohort cannot be classified by guidelines and is habitually presumed psychological origin in clinical practice. Weaker masturbatory erection may be a sign of early cardiovascular risk associated with ED in young men without sexual intercourse. Large sample and multi-centre studies need to be developed for assessing the value of these strategies on early ED diagnosis and treatment.”