Change in testosterone concentrations over time is a better predictor than the actual concentrations for symptoms of late onset hypogonadism.

Background: Symptoms of late-onset hypogonadism (LOH) and concentrations of testosterone (T) and bioavailable testosterone (BT) were studied in relation to the data from the same men 5 years earlier.

Methods: In 2008, 282 men, aged 60-82 years, answered a questionnaire regarding demographic data, medical history, different symptoms of LOH and the 10 questions from the 'Androgen Decline in Aging Males (ADAM)-questionnaire'. Blood samples were analysed for concentrations of T and calculations were made for BT.