Table 5.
Association between serum iron and type 2 diabetes (stratified by copper levels according to physiological status).
| N | Case (%) | OR (95%CI) | p | p interaction | ||
|---|---|---|---|---|---|---|
| Age, years | Copper, µg/dL | |||||
| ≤60 | ≤132.1 | 655 | 149 (22.7) | 1.48 (1.01, 2.12) | 0.046 | 0.054 |
| >132.1 | 702 | 84 (11.9) | 0.82 (0.51, 1.30) | 0.393 | ||
| >60 | ≤132.1 | 444 | 222 (50.0) | 1.73 (1.18, 2.53) | 0.005 | 0.016 |
| >132.1 | 397 | 47 (11.8) | 0.63 (0.33, 1.23) | 0.175 | ||
| Gender | ||||||
| Men | ≤132.1 | 408 | 153 (37.5) | 1.90 (1.22, 2.97) | 0.004 | 0.029 |
| >132.1 | 364 | 47 (12.9) | 0.75 (0.39, 1.45) | 0.398 | ||
| Women | ≤132.1 | 691 | 218 (31.5) | 1.42 (1.01, 1.99) | 0.046 | 0.042 |
| >132.1 | 735 | 84 (11.4) | 0.78 (0.49, 1.24) | 0.288 | ||
| BMI, kg/m2 | ||||||
| ≤24 | ≤132.1 | 483 | 152 (31.5) | 1.71 (1.13, 2.59) | 0.011 | 0.079 |
| >132.1 | 519 | 44 (8.5) | 0.82 (0.43, 1.54) | 0.528 | ||
| >24 | ≤132.1 | 616 | 219 (35.6) | 1.54 (1.08, 2.19) | 0.017 | 0.007 |
| >132.1 | 580 | 87 (15.0) | 0.69 (0.43, 1.11) | 0.125 |
Odds ratios (95% confidence intervals) and p values were obtained from the logistic regression model adjusted for age, gender, body mass index, total cholesterol, and triglycerides. Serum iron was included in the analysis as a binary variable according to the median, with the lower group serving as the reference group. p-values for interaction were assessed using a likelihood ratio test to compare the models with and without interaction terms. BMI, body mass index; OR, odds ratio; CI, confidence interval.