A University of Alberta researcher has discovered a potential breakthrough for premature ejaculation--the most common sexual dysfunction in men--with a drug usually used to treat bi-polar or anxiety disorder.

Dr. Pierre Chue, a psychiatry professor at the U of A, has found success in treating premature ejaculation (PE) with the use of gabapentin, better known by the brand name Neurontin. Chue writes about his findings in the September issue of the "Canadian Journal of Psychiatry."

"This disorder affects almost 40 per cent of males--it is even more common than erectile dysfunction--yet it is not talked about much and there has been very little research on it," said Chue.

The essential feature of the disorder is persistent ejaculation with minimal sexual stimulation before or shortly after penetration and before the person wishes it. PE is believed to be a neurobiological phenomenon involving primarily a disturbance of serotonin receptor function. Currently, physicians prescribe medications that are known to influence these receptors--selective serotonin reuptake inhibitors or SSRIs--that delay ejaculation but these antidepressants also come with negative side-effects..

In his report, Chue cites a case study in which a 40-year-old man diagnosed with PE received minimal effectiveness from different techniques--the use of a condom with topical anesthetic and different antidepressant drugs--aimed to improve the disorder. The drugs resulted in such side effects as restless legs, headaches, decreased libido or accelerated ejaculation. The man "had previously found that alcohol produced satisfactory ejaculatory delay with no loss of erectile capacity, but clearly this was not a feasible regular option," says Chue. A trial of gabapentin taken one to two hours before intercourse proved effective. Higher doses prolonged ejaculation even further but also caused drowsiness.

Dr. Chue is not certain how gabapentin works to improve PE but believes it has to do with the drug's ability to increase aminobutyric acid (GABA), the most important inhibitory neurotransmitter in the brain. Since there are currently no specific treatments for PE, the use of gabepentin to prolong ejaculation warrants further study, says Chue, particularly for those men where other therapies are ineffective or poorly tolerated.

Meanwhile, Chue is looking for people to participate in a clinical trial he is running that will use an SSRI-type drug called dapoxetine, to learn its effects on men with PE. This is an SSRI with a very short half-life that has been shown in clinical trials to delay ejaculation without the usual SSRI side effects.

Source: Science Daily

Men with type 2 diabetes who have difficulty achieving an erection could have heart disease and not realize it, according to a report in today's rapid access issue of Circulation: Journal of the American Heart Association.

Men who had silent, or symptomless, coronary artery disease (CAD) and type 2 diabetes were nine times as likely to have erectile dysfunction (ED) as were diabetic men who did not have silent heart disease.

"If our findings are confirmed, erectile dysfunction may become a potential marker to identify diabetic patients to screen for silent CAD," said lead researcher Carmine Gazzaruso, M.D., an internal medicine specialist at Maugeri Foundation Hospital in Pavia, Italy.

Erectile dysfunction and coronary atherosclerosis (narrowing of the coronary arteries) are frequent complications of diabetes, and the association between erectile dysfunction and overt or symptomatic CAD is well documented. However, many diabetic patients have asymptomatic (silent) CAD and are unaware of their heart disease risk. This is the first study to evaluate the prevalence of erectile dysfunction among men with type 2 diabetes and silent heart disease, researchers said.

"Silent CAD is a strong predictor of coronary events and early death, especially in diabetic patients," the investigators noted. "So, it is of interest to know clinical conditions associated with silent CAD to identify subjects who should be screened for CAD."

To evaluate potential associations between ED and silent coronary artery disease, the Italian group studied 133 men who had uncomplicated diabetes and silent coronary artery disease documented by coronary angiography, a test that produces images inside the heart's blood vessels. They were compared with 127 diabetic men who did not have silent heart disease, as verified by a series of tests.

Men in the two groups were evaluated for ED by means of the International Index of Erectile Function (IIEF), a widely used questionnaire to determine a man's ability to achieve erections. The IIEF was administered to all of the men as part of routine ED screening in the year prior to diagnosis or exclusion of silent CAD.

Diabetic men with and without silent CAD did not differ with respect to current forms of treatment. They also had similar rates of diabetic retinopathy, a diabetes complication that correlates with the severity of the disease.

Among the diabetic men with silent CAD, 33.8 percent had ED, compared to 4.7 percent of diabetic men who did not have silent CAD. A statistical analysis that evaluated potential risk factors for silent CAD showed that ED was a better predictor than more traditional risk factors for CAD. Risk factors for silent CAD were apolipoprotein(a) polymorphism (genetic alteration affecting cholesterol), smoking, microalbuminuria (protein loss related to kidney function), and levels of HDL (good) and LDL (bad) cholesterol.

The findings have several potential implications for the evaluation and management of diabetic patients, Gazzaruso said. First, erectile dysfunction warrants consideration with other CAD risk factors, such as high blood pressure and cholesterol abnormalities, in deciding whether a diabetic man requires more extensive evaluation for coronary artery disease.

A second implication relates to treatment of erectile dysfunction in diabetic men. The availability of oral medications for ED has raised questions about their use in men with cardiovascular disease, not only because the drugs can affect blood pressure, but also because they permit formerly impotent men with heart disease to resume sexual activity. Gazzaruso and his associates suggest that diabetic men with erectile dysfunction might require an exercise test or other evaluation for silent CAD before starting erectile dysfunction medication.

As for the possible biologic or physiologic mechanisms that link ED and silent CAD, the investigators cite microalbuminuria and neurologic disorders as possible explanations. However, they emphasize that more studies are needed to determine the precise nature of the association.

Source: Science Daily

Mayo Clinic researchers report in the latest issue of Mayo Clinic Proceedings that there may be an association between lower urinary tract symptoms and sexual dysfunction among older men. As the population ages, this finding will help further research that could help millions of men.

Lower urinary tract symptoms become common as men age and their prostates enlarge, restricting urine flow or altering their bladder habits. At this same age (age 65 and older) an estimated 100 million men worldwide experience erectile dysfunction. The Mayo Clinic researchers set out to determine whether the urinary tract symptoms and sexual dysfunction are related or not.

"This observation suggests there may be a common cause that someday may prove amenable to medical treatments that could be effective for treating both conditions," says Steven Jacobsen, M.D., Ph.D., a Mayo Clinic researcher and the senior author of the study in the June 2004 issue of Mayo Clinic Proceedings.

The researchers studied 2,115 male patients in The Olmsted County Study of Urinary Symptoms and Health Status Among Men. The men, ages 40 to 79, completed questionnaires in 1990 and were followed up every two years. Dr. Jacobsen says the study in Mayo Clinic Proceedings is one of the few community-based studies to assess the relationship between the symptoms of sexual dysfunction and lower urinary tract symptoms. In contrast, other studies examined only the association between individual urinary symptoms and sexual life dysfunction and lower urinary tract symptoms in selected patients who underwent medical or surgical treatments.

The symptoms that were most strongly associated with sexual dysfunction included a feeling of urgency, having to get up multiple times at night, a weak urine stream and straining to start urinating. These symptoms were all associated with difficulties with getting or maintaining erections, feeling of problems with sexual function and satisfaction. However, they were not strongly associated with sex drive after taking age differences into account.

Source: Science Daily