Table 4.
Effect of OGTT, grouping variables, and clinical variables on plasma total peroxide level according to mixed models with fixed effects. To explore the potential associations between the identified grouping variable predictors to the changes in plasma total peroxide level in women, the mixed model was also adjusted for those variables and for their time interactions that were independent predictors of fasting plasma total peroxide level (CRP) or univariately related (Pearson correlation) to the change in plasma total peroxide level during OGTT (HbA1c). Including all independent determinants of plasma total peroxide level and parameters that show correlation with the change of the total peroxide level after glucose load showed that only HbA1c acts as independent determinant for change in plasma total peroxide level (index ∗ HbA1c).
| Independent variable | Estimate | Sig. |
|---|---|---|
| Intercept | 6.11 (0.58) | 0.000 |
| Previous pregnancy | 0.40 (0.13) | 0.004 |
| Previous insulin treatment | 0.32 (0.17) | 0.058 |
| logCRP | 0.05 (0.02) | 0.015 |
| HbA1c | −0.03 (0.10) | 0.743 |
| Index | 0.96 (0.03) | 0.002 |
| Index ∗ HbA1c | −0.15 (0.05) | 0.004 |
| Index ∗ logCRP | 0.01 (0.01) | 0.194 |
| Index ∗ previous pregnancy | −0.08 (0.07) | 0.234 |
| Index ∗ previous insulin treatment | −0.09 (0.08) | 0.274 |
Dependent variable: log peroxide. N = 61. Values are estimated effect sizes: B (SE) (Although in the table the parameter estimate of index is positive and statistically significant, it does not mean that peroxide level actually increased between the two time points, as it refers to the counterfactual case when all interaction parameters are zero).