Canadian Health&Care Mall: Determinants of sexual function in the aging male
Canadian Health&Care Mall: Determinants of sexual function in the aging male
The prevalence of erectile dysfunction has recently been studied in various countries in Europe and other continents. However, determinants of erectile dysfunction on a An example of a survey in which both prevalence and determinants of erectile dysfunction have been studied is the Krimpen study.
In this study, the prevalence rates of erectile dysfunction and its determinants, and the level of concern about the dysfunction, were studied in a population-based sample of men aged 50 years or over in Krimpen aan den Jssel, a commuter town of about 28 000 inhabitants, near Rotterdam.
The investigated group consisted of 1688 men aged 50–78 years. They were studied by means of self-administered questionnaires, and measurements at a health center and a urology out-patient clinic. The study population represented a 50% response to an invitation to participate.
The prevalence of severe erectile dysfunction (i.e. erections of severely reduced rigidity or no erections) increased from 3 to 26% between the age groups of 50–54 and 70–78 years. Complete absence of erections was rare before the age of 65. One-third of men suffering from severe erectile dysfunction were concerned about the dysfunction, compared with only 8% of men with mild dysfunction (i.e. erections with reduced rigidity). In the same age strata, the prevalence of significant ejaculatory dysfunction (i.e. ejaculations with significantly reduced volume or no ejaculations) increased from 3 to 35%.
The percentage of men who reported to be sexually active also decreased with increasing age, but was still surprisingly high at 69% between 70 and 78 years. Men without marital partners, and men with erectile or ejaculatory dysfunction, were sexually less active than other men in the same age strata. In sexually active men, 17–28% did not have normal erections, indicating that, in older age groups, normal erections are not an absolute prerequisite for a sexually active life. In general, men were less concerned about ejaculatory dysfunction than about erectile dysfunction. Since only a minority of men in the total population were concerned about the dysfunction, the term ‘changed function’ might be better than ‘dysfunction’.
Recently, we conducted a systematic review of studies on the prevalence of erectile dysfunction in the general population6. Accepted guidelines for the reporting of systematic reviews were adhered to. We identified 23 studies, described in 35 articles, that met the inclusion criteria; of these studies, five, 15, two and one were from the USA, Europe, Asia and Australia, respectively. Six studies provided information on all 11 prespecified methodological items; on average 1.8 items were missing.
The reported prevalence rates varied from 2% in men younger than 40 years up to 93% in men older than 80 years. Comparison of prevalence rates is hampered by large methodological differences among the studies. The most important differences are the definition of erectile dysfunction and the type of questionnaire used to measure erectile dysfunction in the various studies. It is obvious that these two issues will have an important impact on the prevalence rates.
Even if there is no true difference in prevalence between two populations, then still the apparent difference could be quite large if different definitions and different questionnaires are used. In general, the more items a questionnaire contains, the greater is the chance that an individual man will score an ‘abnormal’ answer on one of the questions. Furthermore, some studies are conducted only in men who are sexually active or who have a partner available; such studies may underestimate the prevalence of erectile dysfunction.
Traditionally, erectile dysfunction has been associated with several factors:
(1) Cardiovascular disease, including myocardial infarction, coronary artery disease, hypertension, hyperlipidemia, cerebro-vascular accident. The incidence of erectile dysfunction in men with heart disease and hypertension may be double that found in men without these problems8. Indeed erectile dysfunction itself is often a microvascular disease. It has been postulated that erectile dysfunction might be a precursor of more serious vascular disease states. This hypothesis, however, has not yet been proven in a prospective study.
(2) Cigarette smoking and substance abuse including alcohol abuse. An overall effect of smoking is not obvious. Smoking increases the risk for erectile dysfunction in men who have been treated for cardiovascular problems or hypertension. The effects of alcohol are less certain. In smaller quantities alcohol may be protective against vascular disease.
(3) Diabetes. Particularly those men who have vascular, neurological and/or nephrological complications of diabetes mellitus are more likely to suffer from erectile dysfunction.
(4) Surgical or non-surgical pelvic organ trauma can lead to vascular or neural damage. Spinal cord injury or cauda equina syndrome may also cause impotence. Well-known iatrogenic causes include radical prostatectomy, colorectal surgery and aortoiliac vascular surgery. These factors play a minor role on a population level.
(5) Drugs, particularly antidepressants, anti-psychotics, drugs that can lower the blood pressure (antihypertensives), antiarrhythmics and drugs that have endocrine effects such as antiandrogens, steroids and hormone replacement therapy.
(6) Chronic diseases such as chronic obstructive pulmonary disease (COPD), and renal, hepatic, hormonal and neurological disorders.
(7) Psychological factors such as depression, and relationship or marital problems including problems of sexual technique. In the Massachusetts Male Aging Study, however, depression and anger were not associated with incident erectile dysfunction, but new cases were more likely to occur among men who exhibited a submissive personality.
Table 1 summarizes the findings of four studies1–4 that analyzed determinants of erectile dysfunction on a population level. Most of these studies looked at the different factors only in a univariate fashion. The Krimpen study was an exception to this pattern; the following factors were taken into account in a multivariate logistic regression analysis:
Determinants of sexual function in the aging male 11 age, body mass index, symptoms of benign prostatic hyperplasia (lower urinary tract symptoms, LUTS), smoking, COPD, history of cardiac complaints, lower level of education, hypertension (World Health Organization-2 definition), diabetes mellitus, previous prostate operation, alcohol consumption. The following factors were statistically significant independent determinants of severe erectile dysfunction in the multivariate analysis: age, smoking, obesity, level of education, LUTS and treatment for cardiovascular problems as well as COPD.
The parameter ‘population attributable risk’ (PAR) takes into account the prevalence of a certain risk factor in the general population. In the total population, the PAR was greatest for LUTS and obesity.
