Premarin priming does not alter growth hormone release following exercise.

Area of Science:

• Pediatric Endocrinology
• Growth Hormone Physiology
• Diagnostic Screening

Background:

• Assessing growth hormone (GH) deficiency in children is crucial for timely intervention.
• Standard screening tests for GH deficiency include exercise and glucose tolerance tests.
• Estrogen priming (e.g., with Premarin) has been explored to enhance GH release during testing.

Purpose of the Study:

• To evaluate the efficacy of Premarin priming on exercise-induced growth hormone release in prepubertal children.
• To determine the value of combining multiple GH screening agents (estrogen, glucose, exercise) in a large pediatric cohort.
• To assess the impact of age on GH response to screening tests.

Main Methods:

• A study involving 205 short, healthy prepubertal children (below 5th percentile height).
• Group 1 (n=144): Exercise test following glucose ingestion.
• Group 2 (n=61): Estrogen (Premarin) priming before glucose and exercise testing.

Main Results:

• Premarin priming did not significantly increase the number of children responding to exercise or glucose challenges.
• Response rates (GH increase ≥ 8 ng/ml) were high and similar: 86% (non-primed) vs. 88.5% (primed).
• Younger age (≤ 5 years) correlated with lower post-exercise GH levels and higher test failure rates.

Conclusions:

• Premarin priming does not enhance the growth hormone releasing capacity of prepubertal children during exercise.
• Combined screening tests (exercise, glucose, estrogen) offer no advantage over exercise screening alone for GH deficiency diagnosis.
• Glucose loading alone is insufficient to rule out GH deficiency in most children evaluated.