UF study: Prescribed erectile dysfunction drugs don't lead to risky sexual behavior

January 12, 2010

GAINESVILLE, Fla. — Despite studies suggesting that erectile dysfunction drugs promote irresponsible sexual behavior, men who receive prescriptions for them are no more likely to engage in risky sex acts than men who do not receive prescriptions for the medications, according to a University of Florida study.

“For this study we took the perspective of a doctor who may worry that prescribing erectile dysfunction drugs to patients could contribute to the spread of HIV,” said lead researcher Dr. Robert Cook. “The findings from this study should provide some reassurance to health-care providers that erectile dysfunction drugs appear to be prescribed responsibly and used responsibly.”

The study appears in the February issue of the Journal of General Internal Medicine.

“Previous studies have linked erectile dysfunction drugs to risky sexual behavior, but nearly all of those studies have evaluated the behavior of men who obtained erectile dysfunction drugs without a prescription or were already known to be at high risk, such as men who have sex with men, or men who have substance abuse problems,” said Cook, an associate professor in the department of epidemiology and biostatistics in UF’s College of Public Health and Health Professions. “In this study we looked at erectile dysfunction drugs and sexual behavior in the context of routine health care for a group of men who are more representative of the general population.”

The researchers defined risky sexual behavior as having unprotected sex with a partner who has a different or unknown HIV status.

In the United States, three drugs are approved for the treatment of erectile dysfunction, or impotence, in men: Cialis, Levitra and Viagra. Between 15 and 25 percent of 65-year-old men experience erectile dysfunction, according to the National Institute of Diabetes and Digestive and Kidney Diseases. Erectile dysfunction drugs account for more than $3 billion in sales worldwide, according to estimates.

“The question of whether to prescribe an erectile dysfunction drug is an important question related to preventing HIV infection or re-infection among at-risk men primarily because of the magnitude of
prescription use,” said Anthony Silvestre, a professor at the University of Pittsburgh’s department of infectious diseases and microbiology, who was not involved in the study. “While this study’s findings are reassuring to those who prescribe or use the medications, health-care providers should still emphasize HIV prevention with their older patients who request an erectile dysfunction drug.”

For the UF study, researchers examined medical records, participant surveys and pharmacy data for a subset of men participating in the Veterans Aging Cohort Study, an ongoing national study of health outcomes for HIV-positive and HIV-negative veterans sponsored by the National Institutes of Health and the Veterans Health Administration. The men involved in the erectile dysfunction drug use study included 2,787 sexually active men receiving care from Veterans Health Affairs outpatient clinics between 2005 and 2007. Among the men in the sample, 53 percent were HIV-infected and the other 47 percent did not have HIV infection. The mean age of participants was 52.

The researchers found that 28 percent of the men received prescriptions for erectile dysfunction drugs over a one-year period. Erectile dysfunction drugs were more commonly used by men over age 50, who are not white and who had existing health conditions including depression, high blood pressure and diabetes.

Men who took the drugs were just as likely as men who did not use the drugs to report risky sexual behavior. About 10 percent of men in both groups — erectile dysfunction drug users and non-users alike — reported engaging in risky sexual behavior.

Men were more likely to engage in risky sexual behavior if they consumed alcohol over recommended amounts, had sex with other men or used cocaine.

The UF study findings set the stage for doctors to make more informed decisions when prescribing erectile dysfunction drugs, Cook said.

“I think we answered the question of whether or not doctors can prescribe erectile dysfunction drugs without too much concern about causing risky sexual behavior, at least in the VA Health Care System, but doctors should continue to counsel patients on safe behavior,” Cook said.