Male sexual dysfunction is one of the most common health problems affecting men, and is more common with increasing age. The three major forms of male sexual dysfunction are erectile dysfunction, ejaculatory dysfunction and decreased libido.
Erectile dysfunction is a common problem in men over the age of 40 due to hormonal abnormalities, medications, psychological problems, neurologic disease, or vascular insufficiency.
Men with this disorder experience significant psychological distress, which improves if treatment successfully restores erectile function.
Premature ejaculation
Premature ejaculation (PE) is a common problem in males aged 18 to 60 and affects as many as one-in-three men, research shows. Experts say this number is probably much higher, as many men do not always come forward because of fear or embarrassment.
In men who have erectile dysfunction, PE is claimed to be even more common. While many treatments have been devised for this problem, none has been effective in the long-term. Previously available creams took nearly 45 to 60 minutes to work, and usually the individuals had to wear a condom to prevent transmitting the anaesthetic to the partner.
The results from two large studies examining new treatments for PE were presented in Lyon.
The first study found that men with primary PE said they favour daily versus on-demand ingestion of the selective serotonin reuptake inhibitor (SSRI) paroxetine.
Dr Juza Chen of the Tel Aviv Sourasky Medical Centre, Israel, and colleagues reviewed the medical records of 111 men without erectile dysfunction who had been successfully treated for primary PE with paroxetine 20mg for at least two years.
“The organic factors involved in PE are not well understood, but serotonin is important at the level of the central nervous system in the complex regulatory mechanisms involved in ejaculation,” Dr Chen observed, speaking to delegates at the Congress.
“SSRI antidepressants – paroxetine, fluoxetine, and sertraline – and the tricyclic antidepressant clomipramine increase ejaculatory control and delay ejaculation in men with PE, suggesting that pharmacological intervention might be useful for PE.”
While these agents are intended for chronic dosing for treating psychiatric disorders, their pharmacokinetic profiles and pharmacodynamic activity might represent shortcomings when used for treating PE, Dr Chen continued. In fact, these properties might limit the usefulness of these drugs, whether administered on-demand or chronically for the episodic treatment requirements of PE, he said.
“On-demand treatment with SSRIs usually exerts much less ejaculation delay than daily SSRI treatment; however, there is little information available on whether men with chronic PE prefer on-demand or daily drug treatment,” he added.
Participants in the trial were treated with paroxetine either daily or on-demand by their own choice. They were allowed to switch to the other regimen after a trial of at least one month.
Overall, 62 (55.8 per cent) men chose to start the medication on a daily basis, while 49 (44.1 per cent) chose to start using it on-demand.
The results indicate that men prefer daily to on-demand paroxetine for treatment of their PE, Dr Chen concluded.
Erectile dysfunction
Men with mild erectile dysfunction (ED) can achieve substantial clinical benefit from treatment with sildenafil, according to results of an open-label extension phase of an eight-week trial presented at the Congress.
Most of the 152 men enrolled in the trial reported improved erections, and about two-thirds of erections were completely hard and rigid, noted Dr Serge Carrier of McGill University, Montreal, Canada.
At the start of the trial, all men had mild ED, defined as a score of 22 to 25 on the Erectile Function domain of the International Index of Erectile Function (IIEF). Erectile dysfunction had been present for at least three months.
The study found that at the end of open-label treatment, the Erectile Dysfunction Inventory of Treatment Satisfaction (EDITS) score had increased, and 93 per cent of patients were satisfied with sildenafil treatment. The mean score was 86. These results demonstrated a high degree of treatment satisfaction.
In addition, the mean scores for all IIEF domains were significantly improved at the end of the open-label phase compared with the scores at the end of the double-blind treatment phase (P <= .001).
Most adverse events were mild to moderate in severity.
“Very few studies have prospectively assessed a population of men with mild ED,” Dr Carrier pointed out. “Mild ED may affect quality of life as much as moderate or severe ED.”
Testosterone deficiency syndrome
Of the four to five million American men who suffer from hypogonadism, only about two per cent undergo treatment with testosterone replacement therapy, the Congress heard. There are many causes of hypogonadism; including damage to the testes or pituitary gland from infection, trauma, radiation, or chemotherapy treatment, as well as congenital abnormalities such as Klinefelter Syndrome, a rare condition that occurs when a man is born with an extra X chromosome.
A special educational session at the Congress focused on testosterone deficiency, where specialists heard that the highest incidence of hypogonadism is seen in men over the age of 50. About 20 per cent of men over the age of 50 experience hypogonadism and its many symptoms due to a decline in the production of testosterone.
Prof Raymond Rosen of the New England Research Institutes, Watertown, MA, US, reviewed data from key epidemiological studies, explaining that several of these studies have shown that testosterone deficiency is strongly associated with hypertension, hyperlipidaemia, and obesity.
“For example, the Hypogonadism in Males (HIM) study of 2,162 men seeking healthcare for any reason found that men with testosterone levels of below 300 ng/dL were significantly more likely to have these conditions than men with normal testosterone,” said Prof Rosen.
Hypogonadal men had an odds ratio of 2.38 for obesity, 2.09 for diabetes, 1.84 for hypertension, and 1.47 for hyperlipidaemia. “Guay and Jacobson found that in 39 men presenting with organic ED who were also hypogonadal, 92 per cent were insulin-resistant,” added the professor.
However, of 115 men presenting with ED who had normal testosterone, only 25 per cent were insulin-resistant, the same study told. In addition, a community-based study of 864 nondiabetic men in Finland found that the lower a man’s testosterone level, the more likely he was to have metabolic syndrome.
When these men were followed over 11 years, hypogonadal men had more than double the risk of developing metabolic syndrome. Several other studies have shown a similar effect. Scientific studies suggest that the mechanism behind both hypogonadism and diabetes may be alterations in insulin resistance, Prof Rosen said. However, low testosterone is likely to be both an effect and a cause of weight gain and metabolic changes.
