Inter-Assay Growth Hormone and IGF-I Variability
Trial Snapshot
- Phase
- Not Applicable
- Status
- Withdrawn
- Sponsor
- Cedars-Sinai Medical Center
- Enrollment
- 171
Study Overview
Brief Summary
The purpose of this study is to demonstrate the degree of variability in commercially available assays for Growth Hormone measurement in the context of clinical decision making for Growth Hormone (GH) deficiency and Acromegaly and to determine variability among IGF-I inter-assay samples obtained at the time of Growth-Hormone Releasing Hormone Arginine Testing and Oral Glucose Tolerance Testing.
Detailed Description
This research will explore the variability of GH and IGF-1 measurements by commercially available tests. The hypothesis is that the variability in GH and IGF-1 measurement will be sizable enough that different conclusions would be drawn in patient case decision making in the diagnosis and management of GH deficiency and acromegaly.
In order to correctly diagnose disorders of growth hormone secretion, either deficiency or excess, it is necessary to have the accurate measurement of GH (growth hormone) serum and Insulin-like growth factor (IGF-1).
For this study, subjects will be asked to give the Investigators additional blood during either an OGTT (a test for acromegaly) or a growth hormone stimulation test (GHRH-arginine stimulation). Ordinarily, blood would be measured at the beginning and end of the OGTT, and for the GHRH-arginine it would be measured one half hour before the test and then every half hour for 2 hours.
For this study, subjects will provide us with additional blood at the times when blood is drawn for the clinically-indicated tests. No additional needle sticks will be necessary and taking the additional blood will not interfere with the clinical test.
The test we will be doing with the additional blood will be identical to the tests we ordinarily do, but will be done by a different lab. We are testing to see if these results would be the same as our usual lab.
Study Design
- Study Type
- Observational
- Observational Model
- Cohort
- Time Perspective
- Prospective
Eligibility Criteria
- Ages
- 18 Years to — (Adult, Older Adult)
- Sex
- All
- Accepts Healthy Volunteers
- Yes
Inclusion Criteria
- •Male or Female age 18+
- •Clinical indication for testing GH response to secretagogue testing to evaluate for GHD OR clinical indication for testing for GH response to oral glucose load (75grams of glucose) to evaluate for Acromegaly either for diagnosis OR normal volunteer for control group.
- •Normal volunteers will be screened for evidence of pituitary endocrine dysfunction prior to Oral Glucose Tolerance Testing (OGTT) and Growth Hormone Releasing Hormone - Arginine Testing (GHRH-ARG).
- •Able to provide informed consent
Exclusion Criteria
- •Subjects taking GH
- •Pregnant or breast feeding