TABLE 3.
Association of mean A1C in combined treatment groups during DCCT and EDIC with change in common carotid IMT over EDIC years 1, 6, and 12*
| Change in carotid intima-media thickness |
||||||
|---|---|---|---|---|---|---|
| Years 1 to 6 (mm) |
Years 6 to 12 (mm) |
Years 1 to 12 (mm) |
||||
| Mean A1C | β-coefficient† | P | β-coefficient† | P | β-coefficient† | P |
| DCCT | 0.0074 ± 0.0018 | <0.0001 | 0.0038 ± 0.0023 | 0.1052 | 0.0087 ± 0.0026 | 0.0008 |
| DCCT/EDIC to year 1‡ | 0.0079 ± 0.0020 | <0.0001 | 0.0045 ± 0.0025 | 0.0694 | 0.0097 ± 0.0028 | 0.0006 |
| EDIC years 1 to 6, mean | 0.0042 ± 0.0021 | 0.0497 | 0.0071 ± 0.0027 | 0.0075 | 0.0084 ± 0.0030 | 0.0049 |
| DCCT/EDIC to year 6‡ | 0.0082 ± 0.0023 | 0.0003 | 0.0068 ± 0.0028 | 0.0175 | 0.0115 ± 0.0032 | 0.0003 |
| EDIC years 1 to 12 | N/A | N/A | 0.0083 ± 0.0029 | 0.0039 | 0.0103 ± 0.0032 | 0.0016 |
| DCCT/EDIC to year 12‡ | N/A | N/A | 0.0086 ± 0.0031 | 0.0056 | 0.0132 ± 0.0035 | 0.0002 |
N/A, not applicable.
*Separate multiple linear regression models for the change in IMT over each period adjusted for age, sex, study cohort, IMT reader, and image device. Change from years 1 to 6 and change from years 1 to 12 models also adjusted for the year 1 IMT. Change from years 6 to 12 model also adjusted for the year 6 IMT. Separate models with each different A1C measure were performed.
†The β-coefficient (estimated ± SE) is the millimeter change in IMT progression per whole % greater A1C.
‡Weighted mean of DCCT and EDIC A1C values over time, each weighted by the interval of time between values 3 months for each DCCT quarterly A1C value, 12 months for each EDIC annual A1C value.