Table 3.
Associations of osteocalcin concentration, carboxylation, and fragmentation with glucose tolerance, insulin sensitivity, and pancreatic beta-cell function.
| Glucose tolerance (AUC glucose in 2-h OGTT, mg/dL × min) | Insulin sensitivity [clamp, (mg/min)/(uU/mL)] | Pancreatic beta-cell function [AIRg, (uU*min/mL)] | |
|---|---|---|---|
| Osteocalcin concentration, ng/mL (per doubling) | |||
| Model 1 | 33 (−229; 294), p=0.81 | 0.03 (−0.15; 0.21), p=0.73 | −9.1 (−31.1; 12.0), p=0.42 |
| Model 2 | 35 (−228; 297), p=0.80 | 0.05 (−0.13; 0.22); p=0.60 | 0.0 (−30.1; 30.2), p=0.99 |
| Osteocalcin gamma-carboxylation score (per additional mean number of carboxyl-groups) | |||
| Model 1 | −1,295 (−3,147; 558), p=0.17 | 0.21 (−0.82; 1.23), p=0.69 | 69.7 (−158.3; 297.7), p=0.55 |
| Model 2 | −1,126 (−2,942; 690), p=0.22 | −0.21 (−1.40; 0.99), p=0.74 | −14.3 (−192.5; 164.1), p=0.88 |
| Fully uncarboxylated osteocalcin, % of total (per 10 percentage point increase) | |||
| Model 1 | 530 (−248; 1,309), p=0.18 | −0.12 (−0.51; 0.27), p=0.54 | −3.0 (−104.6, 98.6), p=0.95 |
| Model 2 | 472 (−291; 1,235), p=0.23 | 0.02 (−0.43; 0.47), p=0.92 | 20.9 (−63.6; 105.4), p=0.63 |
| Fully uncarboxylated osteocalcin, ng/mL (per doubling) | |||
| Model 1 | 153 (−19; 325), p=0.08 | 0.01 (−0.14; 0.16); p=0.89 | −27.1 (−49.0; −5.2), p=0.02 |
| Model 2 | 99 (−109; 308), p=0.35 | 0.04 (−0.15; 0.23), p=0.68 | −1.3 (−25.8; 23.3), p=0.92 |
| Intact osteocalcin fragments, % of total (per 10 percentage point increase) | |||
| Model 1 | −94 (−959; 770), p=0.83 | 0.30 (−0.11; 0.72), p=0.15 | 74.5 (−49.7; 198.8), p=0.24 |
| Model 2 | 50 (−870; 970), p=0.92 | 0.10 (−0.42; 0.62); p=0.71 | 11.1 (−85.2; 107.5), p=0.82 |
| Intact osteocalcin fragments, ng/mL (per doubling) | |||
| Model 1 | 35 (−274; 344), p=0.82 | 0.08 (−0.13; 0.30), p=0.46 | −2.9 (−29.3; 23.5), p=0.83 |
| Model 2 | 52 (−261; 365), p=0.75 | 0.07 (−0.13; 0.28), p=0.48 | 2.5 (−33.2; 38.2), p=0.89 |
Data shown are beta-coefficients (95% confidence intervals). Abbreviations: AUC: area-under-the-curve, AIRg: acute insulin response to glucose in an intravenous glucose tolerance test. Model 1: unadjusted. Model 2: adjusted for age, sex, race (white/black/other), fat mass, and CKD (yes/no).