Metabolic syndrome, testosterone deficiency and erectile dysfunction never come alone.

Until a decade ago the ailments of elderly men, such as atherosclerosis, hypertension, diabetes mellitus, lower urinary tract symptoms and erectile dysfunction (ED), were regarded as distinct diagnostic/therapeutic entities but there is a growing awareness that these entities are not disparate and, to improve the health of the ageing male, require an integral approach. There is an inter-dependence between the metabolic syndrome, ED and patterns of testosterone in ageing men. The main features of the metabolic syndrome are abdominal obesity, insulin resistance, hypertension and dyslipidaemia, significant factors in the aetiology of erectile function. The metabolic syndrome is associated with lower-than-normal testosterone levels. A new concept of the role of testosterone in male physiology suggests that testosterone plays also a significant role in the development and maintenance of bone and muscle mass and is a determinant of glucose homeostasis and lipid metabolism. Testosterone is not only a factor in libido but exerts also essential effects on the anatomical and physiological substrate of penile erection. With these recent insights, the health problems of elderly men must be placed in a context that allows an integral approach. Treatment of testosterone deficiency is to become part and parcel of this approach.