Risk factors:
(1) older age
(2) obesity
(3) type 2 diabetes
(4) COPD
(5) chronic liver disease
(6) chronic heart disease
(7) chronic kidney disease
(8) chronic inflammatory condition
Clinical features:
(1) reduced libido
(2) erectile dysfunction
(3) diminished physical performance or loss of muscle strength
(4) low energy or mood
(5) variable: small testes, gynecomastia, flushing, reduced bone density
Laboratory features may include:
(1) serum total testosterone may be low or normal (often at the lower limit of the normal reference range)
(2) elevated serum levels of SHBG (sex hormone binding globulin)
(3) elevated serum FSH and/or LH
Differential diagnosis:
(1) other explanations for clinical signs and symptoms
A patient with evidence of late-onset hypogonadism may be a candidate for testosterone replacement therapy. Improvement in symptoms after starting testosterone therapy support the diagnosis.
