Testosterone [Figure 1] is the main male sex hormone. It is responsible for male sexuality and is the main hormone-producing the features associated with masculinity such as substantial muscle mass, facial hair, libido, and sperm production. Besides, the hormone has other vital functions as the basic chemical composition of testosterone is steroidal; and steroids are known to have significant physiological, as well as psychological, effects in male individuals, especially adults. Testosterone production is reduced gradually in men starting from the age of 30. Hence, testosterone blood concentrations slowly diminish as age progresses. As a result, men may experience a number of physiological and psychological events, such as a lack of sex-drive, erectile dysfunction, acute depression, fatigue, low energy levels, and insomnia.
An international consensus document was recently published and provides guidance on the diagnosis, treatment and monitoring of late-onset hypogonadism (LOH) in men. The diagnosis of LOH requires biochemical and clinical components. Controversy in defining the clinical syndrome continues due to the high prevalence of hypogonadal symptoms in the aging male population and the non-specific nature of these symptoms. Further controversy surrounds setting a lower limit of normal testosterone, the limitations of the commonly available total testosterone result in assessing some patients and the unavailability of reliable measures of bioavailable or free testosterone for general clinical use. As with any clinical intervention testosterone treatment should be judged on a balance of risk versus benefit. The traditional benefits of testosterone on sexual function, mood, strength and quality of life remain the primary goals of treatment but possible beneficial effects on other parameters such as bone density, obesity, insulin resistance and angina are emerging and will be reviewed. Potential concerns regarding the effects of testosterone on prostate disease, aggression and polycythaemia will also be addressed. The options available for treatment have increased in recent years with the availability of a number of testosterone preparations which can reliably produce physiological serum concentrations.
Testosterone levels generally peak during adolescence and early adulthood. As you get older, your testosterone level gradually declines — typically about 1 percent a year after age 30 or 40. It is important to determine in older men if a low testosterone level is simply due to the decline of normal aging or if it is due to a disease (hypogonadism).