Table 3.
Discrimination of 5-year incident diabetes using the ARIC risk prediction model: the CARDIA study (2005–2011)
| Overall AUC (95% CI) | AA AUC (95% CI) | Whites AUC (95% CI) | P* | |
|---|---|---|---|---|
| Model 1: previously published regression coefficients† | ||||
| Model 1a: ADA 2004 diagnostic guidelines | 0.846 (0.794, 0.898) | 0.802 (0.721, 0.884) | 0.887 (0.827, 0.947) | 0.10 |
| Model 1b: ADA 2010 diagnostic guidelines | 0.822 (0.782, 0.862) | 0.778 (0.716, 0.840) | 0.860 (0.814, 0.906) | 0.04 |
| P‡ | 0.48 | 0.64 | 0.48 | |
| Model 2: regression equations re-estimated in CARDIA using ADA 2010 diagnostic guidelines§ | ||||
| Model 2a: original predictors | 0.841 (0.806, 0.876) | 0.796 (0.737, 0.854) | 0.875 (0.830, 0.920) | 0.04 |
| Model 2b: original predictors + A1C | 0.863 (0.832, 0.894) | 0.816 (0.763, 0.869) | 0.902 (0.867, 0.936) | 0.008 |
| P∥ | 0.03 | 0.14 | 0.08 |
*P for unpaired receiver operating characteristic comparison of models estimated in AA vs. whites.
†Models 1a and 1b used the following published ARIC prediction model to calculate diabetes risk: probability (diabetes) = [[exp(x)/(1+exp(x))]/9] * 5, where x = −9.9808 + 0.0173 * age in years + 0.4433 * AA race + 0.4981 * 1 if parent history of diabetes is present + 0.0880 * FPG in mg/dL + 0.0111 * SBP in mmHg + 0.0273 * waist circumference in cm − 0.0326 * height in cm − 0.0122 * HDL cholesterol in mg/dL + 0.00271 * triglycerides in mg/dL.
‡P value for unpaired receiver operating characteristic comparison of models estimated within overall cohort, AA, and whites comparing change in model discrimination when diagnostic guidelines are updated from ADA 2004 to ADA 2010 diagnostic guidelines.
§Model 2a included the following predictors from the published ARIC prediction model: age, parent history of diabetes, fasting glucose, systolic blood pressure, waist circumference, height, HDL cholesterol, and triglycerides. Model 2b included the same predictors as model 2a with the addition of A1C.
∥P value for paired receiver operating characteristic comparison of models estimated within overall cohort, AA, and whites comparing change in model discrimination when diagnostic guidelines are updated to include baseline A1C as a predictor.