Men may be less likely to give up on phosphodiesterase type 5 inhibitors (PDE5s) for treatment of erectile dysfunction (ED) if their erections become more rigid, American researchers have found.
PDE5s are often an effective ED treatment and increased rigidity has been associated with greater self-confidence and sexual satisfaction. However, an estimated one-third of men stop taking the drugs after their first prescription. About one-half stop within six months.
Some men find that PDE5s are not as effective as they had hoped. Others stop taking the drugs because they or their partner have lost interest in sex or because the medications are too expensive.
Researchers from the Memorial Sloan-Kettering Cancer Center in New York examined this issue further, focusing on the relationship between erection hardness and treatment adherence.
One hundred sixty-eight men with ED participated in the study. The researchers used the International Index of Erectile Function (IIEF) and the Erection Hardness Scale (EHS) to assess the men’s erections at baseline and at 6-month follow-up points for at least twelve months.
The EHS uses a 4-point scoring system to determine the rigidity of an erection, with a score of 1 indicating severe ED and 4 describing a penis that is “completely hard and fully rigid.”
At the start of treatment, the men were given clear instructions for taking sildenafil. They were told to take the medication on an empty stomach and to expect an approximate 8-hour time frame for sexual activity. Adherence was defined as taking the drug at least once a month.
Generally, the men’s EHS scores improved with treatment. For example, at the start of the study, none of the men achieved an EHS score of 4. However, by the end-of-treatment interview, 46% of the men reached this point.
Eighty-two percent of the men had at least a 1-point improvement in EHS score. Thirty-eight percent saw a 2-point improvement and 11% of the men had a 3-point improvement.
Overall, 67% of the men continued the medication at follow-up. Men who could achieve a score of 4 on the EHS appeared more likely to keep taking sildenafil. Men whose EHS scores jumped two points or more were also more likely to continue.
Partners played an important role in medication adherence. Frequent sexual activity and having a partner, especially one that was at least ten years younger, were predictors of continued sildenafil use. “The fact that having a partner is related to adherence to PDE5 treatment emphasizes that partners should be involved in ED discussions regarding ED management,” the authors noted.
The researchers also recommended “driving patients to a greater rigidity” and aiming for an EHS score of 4. This could lead to fewer men dropping out of the treatment program.
The study was published online in December in the Journal of Sexual Medicine.
The Journal of Sexual Medicine
Mazzola, Clarisse, et al.
“Exploring the Association Between Erectile Rigidity and Treatment Adherence With Sildenafil”
(Full-text. First published online: December 17, 2012)