Why is understanding the relationship of testosterone to cardiovascular risk so important?

Resolution of the uncertainty of the effects of T-therapy on the male cardiovascular system is important from two perspectives. First, men who are androgen deficient due to diseases of the hypothalamus, pituitary, and testes should be considered for T-replacement therapy.11 In these men who have hypogonadism due to pathology of the gonadal axis, it is essential to inform and advise them of potential benefits and possible risks of treatment.12 Second, there has been a marked increase in T prescribing worldwide over the past decades, despite the prevalence of pathological hypogonadism remaining relatively stable.1314 In men who do not have hypothalamic, pituitary, or testicular disease, who are typically older with other medical comorbidities and circulating T that would be regarded as low in younger men, the question arises as to the justification for T treatment and whether potential harms might outweigh anticipated benefits.15 Understanding the extent and the limitations of the existing evidence base would help health practitioners counsel men receiving T treatment for medical indications, may discourage its misuse in men where a medical indication is not clear, and will provide a foundation for future research.

In this Special Issue of the Asian Journal of Andrology, authors from around the world provide reviews of the available evidence of the cardiovascular effects of T on men. These reviews cover epidemiological studies of T and the incidence of cardiovascular events16 and mortality risk,17 RCTs representing mechanistic studies of T and the cardiovascular system,18 T RCTs reporting cardiovascular adverse events,19 and retrospective reviews of T prescription databases.20 These are accompanied by commentaries on the implications for Andrology in the regional context21 and globally for studies of male hormonal contraception.22 Taken together, the content of this Special Issue addresses a pressing debate that affects the care we provide to men with androgen deficiency and future research to preserve health in the expanding population of older men in our communities.