Osteocalcin and type 2 diabetes risk in Latinos: A life course approach.

Objective: To examine associations between circulating levels of the bone-derived protein osteocalcin (OC) and type 2 diabetes (T2D) risk in Latino children and adults. Methods: Serum OC was measured in 136 children and 531 adults who had the following T2D risk factors assessed, body mass index (BMI), Hemoglobin A1c (HbA1c), fasting and 2-hour glucose during an oral glucose tolerance test. Results: OC was significantly higher in children than adults (209.0±12.1 vs. 41.0±0.9 ng/ml, p<0.0001). In adults, OC was inversely associated (all p<0.001) with BMI (r=-0.2), HbA1c (r=-0.2), fasting glucose (r=-0.16), and 2-hour glucose (r=-0.21), while there were no significant associations in children. There was a stepwise decrease in OC with increasing dysglycemia in adults, normoglycemic (44.1±1.3 ng/ml), prediabetic (39.3±1.3 ng/ml), and T2D (31.8±1.2 ng/ml), (p<0.0001), whereas there were no differences between normal and prediabetic youth (195.7±16.1 vs. 194.7±25.8 ng/ml, p=0.3). Conclusions: OC was inversely associated with T2D risk in Latino adults; however, this pattern was not observed in children. Am. J. Hum. Biol. 27:859-861, 2015.