Erectile dysfunction (ED) is an important worldwide health issue that has a significant negative impact on the quality of life and life satisfaction of both the affected individual and his partner. Here we review the prevalence of ED in Asia, associated factors that may influence sexual attitudes and sexual behaviours, and randomized clinical trials (RCTs) of phosphodiesterase-5 (PDE-5) inhibitors to evaluate the clinical efficacy and safety of PDE-5 inhibitors in Asian men. We searched for English-language articles in MEDLINE and PubMed from January 2000 to September 2010. Our results showed that the overall reported prevalence rate of ED in Asia ranged widely, from 2% to 88%. This finding indicates that ED is a common and major health problem in this region. However, sociocultural and economic factors in Asia prevent people from seeking and obtaining appropriate medical care. We found reports on five kinds of PDE-5 inhibitors for the management of ED: sildenafil, vardenafil, tadalafil, udenafil and mirodenafil. The results of RCTs showed that these five PDE-5 inhibitors are more effective than placebo in improving erectile function in Asian men with ED and that these drugs have similar efficacy and safety profiles.
INTRODUCTIONErectile dysfunction (ED) has been defined as the inability to achieve or maintain an erection sufficiently rigid for achieving satisfying sexual intercourse.1 ED is an important worldwide health issue that affects nearly half of men over the age of 40 years, and it has a significant negative impact on the quality of life and life satisfaction of the affected individual as well as his partner.2,3 One of the most frequently cited epidemiological surveys reporting prevalence data for ED is the Massachusetts Male Aging Study.2 The Massachusetts Male Aging Study-the first longitudinal, community-based, randomized, widescale epidemiological study of ED-included 1709 men between the ages of 40 and 70 years who completed a self-reported ED questionnaire. Over that age range, the probabilities of minimal, moderate and complete ED were 16.5%, 17.5% and 4.9%, respectively, at age of 40 years, and 18%, 34% and 15% at age of 70 years, showing that the prevalence of ED increases with age.Another pivotal epidemiological study of sexual dysfunction was the Global Study of Sexual Attitudes and Behaviors (GSSAB), which included 27 500 men and women aged 40-80 years in 29 countries.