Risk Factors of Sexual Dysfunction
Prevalence data for erectile dysfunction appear to be the most clearly supported by evidence-based literature using the stringent criteria outlined in Table 1. Twenty-four studies from around the world regarding prevalence of ED (male sexual arousal dysfunction) from 1993 to 2003 were summarized. Methods of collecting the data varied from study to study. Definition of ED used in each of the studies differed. Time periods covered by the questions about ED varied from a few months to 1 year and, in fact, eight of the studies did not specify a time period question about ED. By region of the world there were 15 studies from Europe (three from the United Kingdom, two each from the Netherlands, Sweden, Finland, and France and one each from Denmark, Germany, Italy, and Spain), five from the United States, one each from Thailand and Japan, and two from Australia. Most were random population studies, some stratified by age or region. Five of the studies were from general practice settings. The percentage responses from populations studied were determined from data presented in the paper or chapter regarding the eligible number who were scheduled to be screened and ranged from 39% to 82%. The number of respondents was not below 200 in any of the studies and only five of the 24 studies were under 500 in number. All of the studies that were stratified by age showed rising prevalence of ED as a population aged. In the full chapter extensive tabulations are made to present these data [8]. Below the age of 40 years the prevalence of ED is 1–9%, in the decade from 40–59 the prevalence range is from 2–9% to as high as 20–30% with some population showing marked differences between the 40–49 age groups compared to the 50–59 year age group. The 50–59 year age group showed the greatest range of reported prevalence rates. Most of the world showed a rather high rate from 20% to 40% for the ages of 60–69 years, some increasing after age 65 except for the Scandinavian reports where the age of 70 years and older is the decade of major prevalence rates change. Almost all of the reports showed high prevalence rates for those men in their 70s and 80s, ranging from 50% to 75% prevalence of ED in these decades.
Five descriptive epidemiological investigations of ejaculatory disturbances fulfilling our validity criteria were chosen [8]. Prevalence rates for ejaculatory disturbances were from a low of 9% up to 31%. These were rates for early ejaculation. Still fewer investigators have reported on the prevalence of delayed ejaculation. One of the problems of surveys regarding early ejaculation is the inconsistency of how the condition is defined. In men it was quite difficult to assess the prevalence of orgasmic dysfunction. In contrast to many men with complete spinal cord injury, some men may be unable to distinguish between ejaculation and orgasm. In the United States and France a prevalence rate for orgasmic dysfunction was from 7% to 8%, although a much lower rate was reported in older Icelandic men (less than 1%). The prevalence of genital pain in men during sexual intercourse has only been fragmentarily studied.
As far as concurrence of sexual dysfunctions, both in the descriptive and analytical epidemiological literature, there is very little on simultaneous occurrence of sexual dysfunctions within and across genders. The association between manifest erectile dysfunction and early ejaculation has been described in men. Recently it was described in Sweden that within both genders (age 18–74) nearly all personal sexual dysfunctions were closely associated [10]. In addition, all women’s dysfunctions were closely coherent with all male partner’s functions/dysfunctions as perceived by the women. Men’s dysfunction had precisely the same close associations with men’s perceptions of their female partner’s functions/dysfunctions. These findings firmly suggest that it is important to think in terms of sexual partner relationship. It is important to know to which extent sexual dysfunctions are accompanied by distress. Among women and men with manifest dysfunctions per se, generally less than half experience that it is accompanied by manifest personal distress. However, among the manifestly personally distressed, the vast majorities were not satisfied with their sexual life.