Table 3. Linear regression between bone mineral density (BMD; g/cm2) and insulin resistance (HOMA1-IR1), insulin sensitivity (HOMA2-S2) and β cell function (HOMA2-β2) in 468 young adults, 2002-2004 Ribeirão Preto cohort, Brazil, fourth follow-up.
| HOMA1-IR | HOMA2-S | HOMA2-β | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Model 1 β1 (95% CI) | p2 | Model 2 β1 (95% CI) | p2 | Model 1 β1 (95% CI) | p2 | Model 2 β1 (95% CI) | p2 | Model 1 β1 (95% CI) | p2 | Model 2 β1 (95% CI) | p2 | |
| BMD - Spinal | ||||||||||||
| Spinal (g/cm2) | -0.2 (-0.8;0.4) | 0.510 | -0.5 (-1.1;0.1) | 0.133 | 0.2 (-0.3;0.8) | 0.432 | 0.4 (-0.2;1.0) | 0.160 | -0.2 (-0.6;0.1) | 0.196 | -0.2 (-0.5;0.2) | 0.424 |
| WC (normal/increased)3 | -0.0 (-1.4;1.3) | 0.936 | -0.2 (-1.6;1.2) | 0.763 | 0.1 (-1.2;1.4) | 0.885 | 0.2 (-1.1;1.5) | 0.760 | -0.1 (-1.0;0.7) | 0.735 | -0.1 (-1.0;0.8) | 0.836 |
| Interaction term | ||||||||||||
| Spinal#WC | 0.6 (-0.7;1.9) | 0.344 | 0.8 (-0.5;2.0) | 0.246 | -0.6 (-1.8;0.6) | 0.324 | -0.7 (-1.9;0.5) | 0.256 | 0.4 (-0.4;1.2) | 0.322 | 0.3 (-0.5;1.2) | 0.401 |
| Osteocalcin (ng/mL) | -0.0 (-0.0;0.0) | 0.230 | -0.0 (-0.0;0.0) | 0.114 | 0.0 (-0.0;0.0) | 0.189 | 0.0 (-0.0;0.0) | 0.139 | -0.0 (-0.0;0.0) | 0.079 | -0.0 (-0.0;0.0) | 0.364 |
| R2 4 | 0.13 | 0.16 | 0.12 | 0.15 | 0.08 | 0.11 | ||||||
| BMD - Femoral neck (FN) | ||||||||||||
| FN (g/cm2) | -0.1 (-0.6;0.3) | 0.553 | -0.5 (-1.0;0.0) | 0.052 | 0.2 (-0.2;0.6) | 0.385 | 0.5 (-0.0;1.0) | 0.066 | -0.3 (-0.6;-0.0) | 0.038 | -0.2 (-0.5;0.1) | 0.245 |
| WC (normal/increased)3 | -0.4 (-1.3;0.5) | 0.395 | -0.3 (-1.3;0.5) | 0.440 | 0.4 (-0.5;1.3) | 0.383 | 0.3 (-0.5;1.2) | 0.457 | -0.2 (-0.8;0.3) | 0.392 | -0.1 (-0.7;0.4) | 0.606 |
| Interaction term | ||||||||||||
| FN#WC | 1.0 (0.1;1.9) | 0.032 | 1.0 (0.1;1.9) | 0.036 | -1.0 (-1.9;-0.1) | 0.033 | -0.9 (-1.8;-0.0) | 0.042 | 0.6 (-0.0;1.2) | 0.061 | 0.4 (-0.1;1.0) | 0.135 |
| Osteocalcin (ng/mL) | -0.0 (-0.0;0.0) | 0.269 | -0.0 (-0.0;0.0) | 0.119 | 0.0 (-0.0;0.0) | 0.228 | 0.0 (-0.0;0.0) | 0.144 | -0.0 (-0.0;0.0) | 0.110 | -0.0 (-0.0;0.0) | 0.378 |
| R2 4 | 0.13 | 0.17 | 0.13 | 0.16 | 0.09 | 0.11 | ||||||
| BMD - Proximal femur (PF) | ||||||||||||
| PF (g/cm2) | -0.1 (-0.5;0.4) | 0.799 | -0.5 (-1.0;0.0) | 0.080 | 0.1 (-0.3;0.5) | 0.571 | 0.4 (-0.1;0.9) | 0.098 | -0.3 (-0.6;-0.0) | 0.047 | -0.2 (-0.5;0.2) | 0.307 |
| WC (normal/increased)3 | -0.2 (-1.2;0.7) | 0.617 | -0.2 (-1.2;0.7) | 0.638 | 0.2 (-0.7;1.2) | 0.605 | 0.2 (-0.7;1.1) | 0.647 | -0.2 (-0.8;0.4) | 0.591 | -0.1 (-0.7;0.5) | 0.726 |
| Interaction term | ||||||||||||
| PF#WC | 0.8 (-0.1;1.7) | 0.090 | 0.8 (-0.1;1.7) | 0.086 | -0.8 (-1.6; 0.1) | 0.091 | -0.7 (-1.6;0.1) | 0.097 | 0.4 (-0.1;1.0) | 0.137 | 0.4 (-0.2;1.0) | 0.205 |
| Osteocalcin (ng/mL) | -0.0 (-0.0; 0.0) | 0.248 | -0.0 (-0.0;0.0) | 0.113 | 0.0 (-0.0;0.0) | 0.212 | 0.0 (-0.0;0.0) | 0.138 | -0.0 (-0.0;0.0) | 0.106 | -0.0 (-0.0;0.0) | 0.373 |
| R2 4 | 0.13 | 0.16 | 0.12 | 0.15 | 0.08 | 0.11 | ||||||
Linear regression coefficient;
p-value refers to linear regression.
Categorized using World Health Organization cutoff points, normal WC: < 80 cm for women and < 94 cm for men; increased WC: ≥ 80 cm for women and ≥ 94 cm for men.
R2 refers to the outcome variation explained by the models.
Model 1 was adjusted only for osteocalcin and the interaction between BMD and WC, Model 2 was further adjusted for physical activity, smoking, alcohol intake, sex, age and skin color. All the multiple models were statically significant (p-value < 0.001).
CI: confidence interval; HOMA: homeostatic model assessment; HOMA1-IR: insulin resistance; HOMA2-S: insulin sensitivity; HOMA2-β: β-cell function (insulin secretion); WC: waist circumference; BMD: bone mineral density.