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. RESULTS A total of 87.2% of the questionnaires were returned and analysed, and 75.2% of the responders gave blood samples. The oldest third of the men were most affected by LOH symptoms (p < 0.05). Both T and BT concentrations decreased during the 5 years (p < 0.05) but only the symptom 'less strong erections' changed significantly (p < 0.05). Men reporting one of the four specific symptoms from the 'ADAM-questionnaire' for the first time in 2008 had a higher loss of T and BT than men who had unchanged or fewer symptoms than that reported in 2003. CONCLUSIONS The magnitude of the decrease in concentrations is a better predictor of LOH than are the actual concentrations of T and BT. A combination of symptoms predicts LOH better than any single symptom.