Table 4.
Summary of multivariable logistic regressions of AGE associations with the prevalence of nephropathy without and with adjustment for A1C level, and vice versa
| Covariate effects evaluated* | df | χ2 | P value | Entropy R2 | OR (95% CI)† |
|---|---|---|---|---|---|
| All AGEs (FUR, CML, pentosidine, fluorescence, acid-soluble collagen, pepsin-soluble collagen, CEL, G-H1, MG-H1, GSPNE) | |||||
| Unadjusted | 10 | 24.0 | 0.008 | 0.11 | |
| Adjusted for | |||||
| DCCT mean A1C | 10 | 9.6 | 0.48 | 0.04 | |
| EDIC study mean A1C | 10 | 18.1 | 0.05 | 0.08 | |
| Original AGEs published in 2005 (FUR, CML, pentosidine, fluorescence, acid-soluble collagen, pepsin-soluble collagen) | |||||
| Unadjusted | 6 | 21.2 | 0.002 | 0.10 | |
| Adjusted for | |||||
| DCCT mean A1C | 6 | 6.8 | 0.34 | 0.03 | |
| EDIC study mean A1C | 6 | 15.3 | 0.02 | 0.07 | |
| Backward-selected AGEs (FUR) | |||||
| Unadjusted | 1 | 21.5 | <0.0001 | 0.10 | 2.3 (1.6–3.3) |
| Adjusted for | |||||
| DCCT mean A1C | 1 | 5.1 | 0.02 | 0.02 | 2.0 (1.0–3.2) |
| EDIC study mean A1C | 1 | 13.1 | 0.0003 | 0.06 | 2.0 (1.3–2.5) |
| CML, pentosidine, fluorescence, acid-soluble collagen, pepsin-soluble collagen, CEL, G-H1, MG-H1, GSPNE | 1 | 11.7 | 0.0006 | 0.05 | 2.0 (1.0–3.2) |
| Selected factors‡ | 1 | 3.9 | 0.049 | 0.02 | 2.5 (1.3–5.0) |
| DCCT mean A1C effect | |||||
| Unadjusted | 1 | 18.8 | <0.0001 | 0.08 | 3.0 (1.5–2.1) |
| Adjusted for | |||||
| FUR, CML, pentosidine, fluorescence, acid-soluble collagen, pepsin-soluble collagen, CEL, G-H1, MG-H1, GSPNE | 1 | 0.8 | 0.38 | 0.0 | 1.3 (0.7–2.2) |
| Backward-selected AGEs (FUR) | 1 | 1.4 | 0.23 | 0.01 | 1.4 (0.8–2.3) |
| EDIC study mean A1C effect | |||||
| Unadjusted | 1 | 44.0 | <0.0001 | 0.20 | 3.4 (2.2–5.1) |
| Adjusted for | |||||
| FUR, CML, pentosidine, fluorescence, acid-soluble collagen, pepsin-soluble collagen, CEL, G-H1, MG-H1, GSPNE | 1 | 34.1 | <0.0001 | 0.16 | 3.2 (2.0–5.0) |
| Backward-selected AGEs (FUR) | 1 | 33.8 | <0.0001 | 0.15 | 3.1 (2.0–4.8) |
*Within each block, multiple model effects are presented using the set of variables named within each block. For the first block, the joint effect of all 10 AGEs is assessed. The unadjusted model shows the effect of the named variables without adjustment for other factors (e.g., the effect of the 10 AGEs in combination). This is followed by the effect of the covariates after adjustment for one or more specified factors, each from a separate model (e.g., the effect of the 10 AGEs in a model adjusted for the DCCT mean A1C and in a model adjusted for the EDIC study mean A1C).
†Odds ratio (OR) is based on 1 SD increase in the continuous variables (DCCT mean A1C 1.6% [17.5 mmol/mol], EDIC study mean A1C 1.1% [12.0 mmol/mol], FUR 231, GSPNE 0.66, MG-H1 0.44).
‡A model adjusted for the following factors that were nominally, statistically, and significantly associated with the outcome in univariate analyses in Table 2: DCCT mean A1C, EDIC study mean A1C up to year 16, and both retinopathy and log(AER) at EDIC study baseline.