TRH tests in a healthy elderly population. Demonstration of gender differences.

Thyrotropin releasing hormone (TRH) tests were conducted in 99 healthy elderly men and women between the ages of 65 and 89. The TRH test identified elderly patients with subclinical thyroid dysfunction not recognized by basal TSH values alone. Men revealed significantly diminished TSH responses to TRH injection relative to women. Mean delta max TSH was 9.0 +/- 8.3 microIU/mL in men vs 15.7 +/- 14.8 microIU/mL in women (P less than .01) reflecting the need to consider gender effect in the interpretation of TRH test responses.