Andropause

Strictly, “andropause” does not exist — unlike the female menopause there is no precipitous, universal loss of gonadal function in men.

What occurs is a gradual, variable decline in testosterone with a continuously rising prevalence of low levels; this is termed late-onset hypogonadism (LOH).

Even the term LOH is imperfect, because the decline is continuous throughout adult life, not confined to old age.

LOH is defined as an age-associated clinical and biochemical syndrome with symptoms and signs of hypogonadism plus serum testosterone below the young adult reference range.

Although hypogonadal symptoms occur at least once in life in most men after age 50, the prevalence of true LOH is only about 2–3%.

Hypogonadism is common but under-diagnosed and under-treated in older men — only an estimated 5–35% of hypogonadal men receive treatment.

Prevalence rises with obesity, type 2 diabetes, metabolic syndrome, chronic illness, opioid use and glucocorticoid therapy — i.e. it is largely comorbidity-driven, not age-driven.

A combined primary and secondary defect: reduced Leydig-cell responsiveness to LH (testicular) plus reduced episodic and stimulated gonadotrophin secretion (hypothalamo-pituitary).

SHBG rises with age, so free testosterone falls faster than total testosterone; measuring only total testosterone underestimates the deficit.

Hypogonadotropic hypogonadism is frequent in type 2 diabetes and obesity, mediated by insulin resistance, inflammation and aromatisation of androgen to oestrogen in adipose tissue — this form is often reversible.

Sexual symptoms are the most specific: loss of morning erections, reduced sexual thoughts, and erectile dysfunction.

Non-specific symptoms overlap heavily with ageing and comorbidity: fatigue, low mood, poor concentration, reduced muscle mass and strength, increased visceral fat, decreased bone density, hot flushes, sweating and sleep disturbance.

Because of this overlap, screening questionnaires (ADAM, AMS) are sensitive but have poor specificity and are not recommended for case-finding.

Exclude depression, hypothyroidism, obstructive sleep apnoea, anaemia, chronic kidney or liver disease, malignancy, alcohol excess, opioids and glucocorticoids before attributing symptoms to testosterone.

Confirm biochemically with two morning samples, plus LH/FSH, prolactin and (if indicated) pituitary imaging.

First-line management is not hormonal: weight reduction, exercise (especially resistance training), treatment of sleep apnoea and diabetes, and withdrawal of opioids or glucocorticoids where possible.

Testosterone therapy is reserved for men with both low testosterone and clinically important symptoms, after explicit discussion of risks and with the same monitoring and contraindications as any testosterone replacement.

Related age-related declines — “adrenopause” (DHEA) and “somatopause” (GH/IGF-1) — are similarly not indications for routine replacement; there is no indication for testosterone treatment in the majority of adult men.