Endocrine Abstracts

Oral but not transdermal ORT reduces serum IGF-1 levels in postmenopausal women. The effect of ORT type on GH dose and sensitivity is unclear. We present a retrospective analysis of GH-deficient women on ORT in the KIMS database.

AIM: To determine the type of oestrogen prescribed and its effect on GH dose.

METHOD: Patients were divided into groups taking oral oestradiol valerate, conjugated oestrogen, ethinyloestradiol and transdermal oestradiol. GH sensitivity was calculated as the change in IGF-1 SDS/unit GH/day after a year. ANOVA and Mann-Whitney or t-tests were used to determine statistical differences between groups.

RESULTS: 897 patients were on ORT at least a month prior to entering KIMS database. 77.9 percent were aged 50 years or less, 46.9 percent had never been treated with GH and 69.8 percent had adult-onset pituitary disease. 17.8 percent were on conjugated oestrogen, 24.3 percent on ethinyloestradiol, 42.4 percent on oral oestradiol and 15.5 percent on transdermal oestradiol. Patients on ethinyloestradiol compared to patients taking conjugated oestrogen, oral and transdermal oestradiol, were younger [median (range) age 30.9 (21.0-46.4) versus 45.9 (26.1-57.7), 42.8 (24.5-58.3) and 47.7 (30.3-60.3) years respectively, p less than 0.001] and were on higher GH doses independent of age [median (range) GH dose 2.00 (1.00-3.00) versus 1.60 (0.80-2.40), 1.60 (0.80-2.40) & 1.20 (0.80-2.40) IU/day respectively, p less than 0.001). There was no difference in GH doses between patients taking oral oestradiol and conjugated oestrogen, and patients taking oral and transdermal oestradiol after correction for age. Patients taking transdermal oestradiol were on lower GH doses compared to patients taking conjugated oestrogen (p=0.0066) independent of age. There was no difference in GH sensitivity between all groups of ORT after correction for age.

CONCLUSION: GH-deficient patients taking ethinyloestradiol are on higher GH doses but have no difference in GH sensitivity compared to patients taking other ORT.