Premium
IGF‐1 and IGF‐Binding Proteins and Bone Mass, Geometry, and Strength: Relation to Metabolic Control in Adolescent Girls With Type 1 Diabetes
Author(s) -
MoyerMileur Laurie J,
Slater Hillarie,
Jordan Kristine C,
Murray Mary A
Publication year - 2008
Publication title -
journal of bone and mineral research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.882
H-Index - 241
eISSN - 1523-4681
pISSN - 0884-0431
DOI - 10.1359/jbmr.080713
Subject(s) - endocrinology , metabolic control analysis , bone mass , medicine , relation (database) , diabetes mellitus , type 2 diabetes , geometry , mathematics , osteoporosis , computer science , data mining
Abstract Children and adolescents with poorly controlled type 1 diabetes mellitus (T1DM) are at risk for decreased bone mass. Growth hormone (GH) and its mediator, IGF‐1, promote skeletal growth. Recent observations have suggested that children and adolescents with T1DM are at risk for decreased bone mineral acquisition. We examined the relationships between metabolic control, IGF‐1 and its binding proteins (IGFBP‐1, ‐3, ‐5), and bone mass in T1DM in adolescent girls 12–15 yr of age with T1DM ( n = 11) and matched controls ( n = 10). Subjects were admitted overnight and given a standardized diet. Periodic blood samples were obtained, and bone measurements were performed. Serum GH, IGFBP‐1 and ‐5, glycosylated hemoglobin (HbA 1c ), glucose, and urine magnesium levels were higher and IGF‐1 values were lower in T1DM compared with controls ( p < 0.05). Whole body BMC/bone area (BA), femoral neck areal BMD (aBMD) and bone mineral apparent density (BMAD), and tibia cortical BMC were lower in T1DM ( p < 0.05). Poor diabetes control predicted lower IGF‐1 ( r 2 = 0.21) and greater IGFBP‐1 ( r 2 = 0.39), IGFBP‐5 ( r 2 = 0.38), and bone‐specific alkaline phosphatase (BALP; r 2 = 0.41, p < 0.05). Higher urine magnesium excretion predicted an overall shorter, lighter skeleton, and lower tibia cortical bone size, mineral, and density ( r 2 = 0.44–0.75, p < 0.05). In the T1DM cohort, earlier age at diagnosis was predictive of lower IGF‐1, higher urine magnesium excretion, and lighter, thinner cortical bone ( r 2 ⩽ 0.45, p < 0.01). We conclude that poor metabolic control alters the GH/IGF‐1 axis, whereas greater urine magnesium excretion may reflect subtle changes in renal function and/or glucosuria leading to altered bone size and density in adolescent girls with T1DM.