Objective: To investigate the prevalence of erectile dysfunction (ED) in the South Australian community, and the influence of demographic and other risk factors.
Design: Survey by mailed questionnaire (based on the University of California, Los Angeles prostate cancer index) of a subset (men who agreed to participate) of a probability sample of the South Australian community who completed a multiuser interview survey.
Participants and setting: Men over the age of 40 in South Australia.
Main outcome measures: Sexual desire, orgasm, ability to have an erection, adequacy (firmness) of erections for intercourse, frequency of erections when wanted, frequency of intercourse, nocturnal or morning erections, and history of prostate surgery; total sexual function score based on these.
Results: 612 men (86.7%) agreed to answer the sexual function survey; 427 (69.8%) returned questionnaires. ED was strongly correlated with age in all seven domains of sexual function. Erections inadequate for intercourse affected 3% of 40-49-year-olds, increasing to 64% of 70-79-year-olds. The frequency of intercourse considered normal for age by men 50-69 years was 1-6 times weekly; the disparity between this and reported frequency increased in men over 60 years, as did the difference between sexual desire and potency. A history of vigorous exercise was protective across all ages. High triglyceride levels, blood pressure medication and non-cancer surgery for prostate disease were independent predictors of poor sexual function at older ages. High cholesterol level was an independent predictor of impotence.
Conclusions: We found similar or higher levels of ED than in comparable overseas studies. Disparity between potency and desire was greatest, and hence the age group in whom demand for treatment may be highest, in those 60 years and older. Cardiovascular risk factors were predictors of ED in these older men, suggesting that prevention may benefit sexual function. Non-cancer prostate surgery may be a greater contributor to ED than previously realised.