IGF- 1 levels are dependent on the amount of growth hormone in the blood but can also be low in normal, young children, so the test must be interpreted carefully. A more accurate but still imperfect way to diagnose growth hormone deficiency is a growth hormone stimulation test. Jan 10, · A growth hormone deficiency (GHD) occurs when a person’s pituitary gland does not produce enough growth hormone. It is a condition common in children.
It has long been known that insulin-like growth factor 1 (IGF1) causes an increase in the circulating levels of 1,dihydroxyvitamin D (1,25(OH) 2 D), the hormonally active vitamin D metabolite, by stimulating the expression and activity of the 1α-hydoxylase that produces 1,25(OH) 2 D in the kidney (1, 2). IGF-1 is best known for its role in muscle building and repair. During childhood, IGF-1 works in conjunction with other growth hormones to help children grow normally. Among adults, IGF-1 is known to: Promotes repair of skeletal muscles. Respond to exercise. During and after workouts, HGH levels go up, causing a rise in the levels of IGF
IGF-1 is a mediator of the effects of growth hormone, and its level in the bloodstream remains stable throughout the day. This marker is used to help doctors determine GH deficiency in adults, as well as the dosage of HGH to prescribe based on the level of hormonal decline. Testing Procedure. Insulin‐like growth factor‐1 (IGF‐1) is the principal hormonal mediator of statural growth. IGF‐1 must be present in order for children's bones, cartilage, and organs to grow normally. Under typical circumstances, growth hormone (GH) binds to its receptor in the liver and other tissues, and stimulates the synthesis/secretion of IGF‐1.
A normal level of IGF-1 does not exclude presence of GH deficiency in adults ; studies show that 37 to 70% of GH deficient adults have normal IGF-1 levels. [16, 17] An explanation for this discordance is that the regulation of IGF1 production in the liver is . In adults, decreased production can lead to low bone density, less muscle mass, and altered lipid levels. However, testing for IGF-1 deficiency or GH deficiency is not routinely done in adults who have decreased bone density and/or muscle strength or increased lipids.