IGF-I and Free Fatty Acids Isn Glucose Metabolism in Acromegaly
Background Glucose metabolism abnormalities are frequent in acromegaly. Insulin resistance (IR) correlates with the intensity of acromegaly and Insulin-like Growth factor-I (IGF-I) correlates better with IR than growth hormone (GH). Insulin secretion (IS) is significantly reduced in hyperglycemic acromegalics as compared with those with normal glucose levels. IS is independent of acromegaly intensity.
The aim of this study is to show that in active acromegaly: 1) IGF-I does not cause IR but is just a better marker of acromegaly intensity than GH; 2) high GH levels induce IR through free fatty acids (FFA); 3) hyperglycemia is caused by a defficient IS on a background of IR.
Methods Intensity of acromegaly will be assessed using serum levels of GH, IGF-I and IGF binding globulin-3. IR and IS will be assessd using an intravenous glucose tolerance test acording to Bergman model. FFA will be directly measured in plasma.
|Study Design:||Observational Model: Case-Only
Time Perspective: Prospective
|Official Title:||The Role of Insulin-like Growth Factor-I (IGF-I) and Free Fatty Acids in Insulin Resistance, Insulin Secretion and Glucose Metabolism Abnormalities in Acromegaly|
- The correlation coefficient between IGFBP-3 and insulin resistance assessed using Bergman model is non-inferior to the correlation coefficient between IGF-I and insulin resistance [ Time Frame: 2 years ]
- Free fatty acids correlates significantly with insulin resistance assessed using Bergman model [ Time Frame: 2 years ]
- Disposition index calculated using Bergman model is significantly reduced in subjects with glucose intolerance than in subjects with normal glucose tolerance [ Time Frame: 2 years ]
- GH, IGF-I and IGFBP-3 significantly correlates with insulin resistance calculated using Bergman model [ Time Frame: 2 years ]
- GH, IGF-I and IGFBP-3 significantly correlates with free fatty acids [ Time Frame: 2 years ]
- GH, IGF-I and IGFBP-3 does not correlate with insulin sensitivity calculated using Bergman model [ Time Frame: 2 years ]
- GH, IGF-I and IGFBP-3 does not correlate with disposition index [ Time Frame: 2 years ]
- Disposition index after reduction of acromegaly activity by various treatments [ Time Frame: 3 months after surgery or start of medical treatment ]
|Study Start Date:||March 2014|
|Estimated Study Completion Date:||December 2016|
|Estimated Primary Completion Date:||December 2016 (Final data collection date for primary outcome measure)|
Please refer to this study by its ClinicalTrials.gov identifier: NCT02084095
|Contact: Dan A Niculescu, MDfirstname.lastname@example.org|
|"C. I. Parhon" Institute of Endocrinology||Recruiting|
|Bucharest, Romania, 011863|