Table 2.
Calculated means (95% confidence interval) of insulin, glucose, HOMA-IR, QUICKI across quartiles of serum magnesium after adjusting covariates.
| Q1 | Q2 | Q3 | Q4 | Nominal P value for trend a | |
|---|---|---|---|---|---|
| Fasting insulin | |||||
| Model 1 b | 107.2 (106.7-107.7) | 100.3 (100.0-100.5) | 95.2 (95.0-95.5) | 87.6 (86.9-88.3) | 0.401 |
| Model 2 c | 104.3 (99.6-109.0) | 98.8 (94.0-103.6) | 99.1 (94.6-103.5) | 86.9 (82.6-91.2) | 0.219 |
| Model 3 d | 102.9 (89.2-116.5) | 96.9 (86.3-107.5) | 89.7 (80.0-99.4) | 89.4 (80.3-98.6) | 0.078 |
| Fasting glucose | |||||
| Model 1 b | 5.26 (5.25-5.28) | 5.10 (5.10-5.11) | 4.99 (5.00-5.01) | 4.82 (4.80-4.84) | <0.001 |
| Model 2 c | 5.25 (5.22-5.28) | 5.10 (5.07-5.13) | 5.01 (4.99-5.04) | 4.82 (4.78-4.85) | <0.001 |
| Model 3 d | 5.26 (5.11-5.40) | 5.20 (5.08-5.32) | 4.96 (4.84-5.07) | 4.76 (4.66-4.87) | <0.001 |
| HOMA-IR | |||||
| Model 1 b | 3.82 (3.78-3.86) | 3.40 (3.37-3.42) | 3.12 (3.10-3.15) | 2.65 (2.60-2.69) | 0.002 |
| Model 2 c | 3.74 (3.57-3.91) | 3.34 (3.17-3.50) | 3.25 (3.09-3.41) | 2.62 (2.46-2.78) | <0.001 |
| Model 3 d | 3.75 (3.13-4.36) | 3.38 (2.95-3.81) | 3.00 (2.61-3.38) | 2.86 (2.50-3.21) | <0.001 |
| QUICKI | |||||
| Model 1 b | 0.336 (0.335-0.336) | 0.340 (0.340-0.341) | 0.343 (0.343-0.344) | 0.349 (0.348-0.349) | 0.044 |
| Model 2 c | 0.338 (0.335-0.341) | 0.341 (0.338-0.344) | 0.341 (0.339-0.344) | 0.349 (0.346-0.352) | 0.009 |
| Model 3 d | 0.341 (0.334-0.347) | 0.336 (0.331-0.342) | 0.345 (0.339-0.351) | 0.347 (0.341-0.352) | 0.003 |
HOMA-IR, homeostatic model assessment of insulin resistance; QUICKI, quantitative insulin-sensitivity check index.
a
Linear trends across quartiles of serum magnesium were evaluated by entering the median values of each category into the generalized linear model.
b
Model 1 adjusted for age.
c
Model 2 additionally adjusted for body mass index, waist circumference, hip circumference, systolic blood pressure, diastolic blood pressure.
d
Model 3 additionally adjusted for total testosterone, estradiol, follicle-stimulating hormone, luteinizing hormone, and sex hormone-binding globulin.