Male hypogonadism--a non-specific consequence of illness.

Depressed thyroid hormone levels are commonly found in sick patients. Low serum testosterone concentrations have also been described in men suffering from a number of illnesses. To investigate whether this might be a non-specific marker of illness, various endocrine parameters were measured in 30 male patients in a general medical ward. Patients were suffering from a wide spectrum of medical disorders and were not receiving drugs known to affect endocrine function. Results were compared with a healthy age-matched control group. Serum testosterone concentrations (mean +/- SE) were low in the patient group (8.9 +/- 1.1 vs. 18.2 +/- 1.4 nmol/l, p less than 0.001), correlated significantly with serum T3 levels but were not related to prognosis. Half the patients had testosterone levels below the normal control range. Changes in testosterone concentrations could not be explained on the basis of binding protein changes, hyperprolactinaemia or depressed pituitary secretion of gonadotrophins. Depression of serum testosterone concentrations is a non-specific marker of illness.