Table 1.
β-Coefficients (95% CIs) for the relationship between HbA1c and indices of insulin resistance and β-cell function and MMSE
| N | All | Age (years)† |
Sex‡ |
|||||
|---|---|---|---|---|---|---|---|---|
| <70 | ≥70 | P for interaction | Men | Women | P for interaction | |||
| HbA1c (%) |
4,335 |
−0.02 (−0.14, 0.10) |
0.00 (−0.13, 0.14) |
−0.05 (−0.30, 0.19) |
0.73 |
0.02 (−0.12, 0.17) |
−0.07 (−0.28, 0.15) |
0.31 |
| Median split | ||||||||
| <7.1% |
2,148 |
0.50 (0.09, 0.90)* |
0.21 (−0.25, 0.66) |
1.06 (0.29, 1.83)* |
0.06 |
0.36 (−0.12, 0.83) |
0.65 (−0.06, 1.37) |
0.36 |
| ≥7.1% |
2,187 |
−0.27 (−0.49, −0.04)* |
−0.07 (−0.32, 0.19) |
−0.70 (−1.15, −0.25)* |
0.01* |
−0.11 (−0.37, 0.15) |
−0.51 (−0.91, −0.11)* |
0.04* |
| Only patients without use of sulfonylurea or glinide | ||||||||
| β-Cell function | ||||||||
| C-peptide (nmol/L) |
2,027 |
0.06 (−0.20, 0.32) |
0.05 (−0.25, 0.35) |
0.01 (−0.51, 0.53) |
0.87 |
−0.08 (−0.36, 0.21) |
0.39 (−0.16, 0.93) |
0.19 |
| Proinsulin (qmol/L) |
2,232 |
−0.003 (−0.006, −0.001)* |
−0.002 (−0.005, 0.001) |
−0.007 (−0.015, 0.001) |
0.30 |
−0.002 (−0.005, 0.001) |
−0.006 (−0.012, 0.001) |
0.31 |
| Proinsulin–to–C-peptide ratio |
2,011 |
−0.051 (−0.082, −0.021)* |
−0.045 (−0.077, −0.012)* |
−0.054 (−0.126, 0.018) |
0.96 |
−0.021 (−0.053, 0.012) |
−0.114 (−0.176, −0.052)* |
0.01* |
| HOMA2-β |
2,026 |
0.0006 (−0.0037, 0.0024) |
−0.0010 (−0.0043, 0.0024) |
−0.0008 (−0.0074, 0.0057) |
0.98 |
−0.0011 (−0.0044, 0.0021) |
0.0004 (−0.0058, 0.0067) |
0.54 |
| Insulin resistance | ||||||||
| HOMA2-IR | 2,026 | 0.0119 (−0.0859, 0.1096) | 0.0101 (−0.1011, 0.1212) | −0.0085 (−0.2085, 0.1915) | 0.84 | −0.0407 (−0.1444, 0.0630) | 0.1432 (−0.0626, 0.3491) | 0.18 |
Estimates for all patients are obtained from an ANCOVA with factors of sex and race (for HbA1c, also use of sulfonylurea or glinide) and covariates of age, years of formal education, and baseline value of interest. Estimates within subgroup HbA1c (<7.1%, ≥7.1%) are obtained from an ANCOVA using the same model within the HbA1c subgroup.
*P < 0.05.
†For the subgroup age (<70, ≥70 years), the same models without covariate age were run.
‡For the subgroup sex, the same models without factor sex were run. Interaction P values are taken from models as above with the additional subgroup term (subgroup age or sex, respectively) and interaction term (subgroup age × baseline value of interest or sex × baseline variable of interest, respectively).