Until the last 10 years we have had little detailed information concerning the prevalence of ED. The first modern study was the Massachusetts Male Aging Study (MMAS), published in 1994, and since then a number of similar epidemiological studies have been undertaken in other countries. Although the methodology has varied a number of common themes have emerged, which are outlined below. Erectile dysfunction is common. The MMAS study suggested that around 50% of men over the age of 40 suffered from ED. However, it was also clear that many of these cases were not severe, and this has been confirmed in subsequent studies. Overall, in the MMAS 35% of men between the ages of 40 and 70 had moderate or severe ED.
The prevalence of erectile dysfunction increases with age
The prevalence of ED increases with increasing age, such that, if we restrict ourselves to patients with moderate and severe ED, then around 10% of men in their 40s, around 20% of men in their 50s, around 40% of men in their 60s and 60% of men in their 70s are affected. Similarly, the incidence of newly developing cases of ED also increases with increasing age. Erectile dysfunction shows some geographical and cultural variation The prevalence of ED is broadly similar across a range of countries with different cultures. However, there is variation, with some countries (such as Turkey) appearing to have a substantially higher incidence, particularly in older men.The possible reasons for these differences are multiple, and include different cultural attitudes towards sexual activity and differing rates of vascular disease. Unfortunately, the methods of assessing ED were not the same in each study, so any comparisons cannot be definitive. Erectile dysfunction is associated with other conditions, including vascular disease and its risk factors.
Most of the studies looked at risk factors for erectile dysfunction and most found significant associations with a variety of diseases, including:
- Cardiovascular disease (approximately increased relative risk×2),
- Diabetes (approximately increased relative risk×3–4)
- Hypertension (approximately increased relative risk×1.5–2)
- Depression (approximately increased relative risk×2–3.5)
- Lower urinary tract symptoms (approximately increased relative risk×1.5–2).
Erectile function is associated with a number of lifestyle issues
There is increasing evidence that exercise is beneficial for sexual function, as is modest alcohol consumption, whereas increasing body mass index (BMI) and excessive alcohol consumption lead to increased erectile dysfunction. Although intuitively we would expect to find that ED is associated with cigarette smoking, the data are inconclusive in this respect.
Summary
■ Significant erectile dysfunction is present in around a third of men over 40 years of age
■ The prevalence of ED:
■ Increases with age
■ Is strongly associated with vascular risk factors
■ Is also associated with psychosocial issues
■ Is broadly similar in different races and cultures
■ Normal erectile function is associated with ‘healthy’ living