The association and discordance between glycated hemoglobin A1c and glycated albumin, assessed using a blend of multiple linear regression and random forest regression

Abstract

BackgroundDue to a high prevalence of thalassemia in southwest China, the diagnostic value of glycated hemoglobin A1c (HbA1c) is limited in the local population. Glycated albumin (GA) must also be measured for glucose monitoring. We sought to explore the relationships between HbA1c and GA. MethodsWe analyzed 3,414 participants and allocated to four groups: GA > 14% and HbA1c > 5.7% (group 1), GA > 14% and HbA1c ≤ 5.7% (group 2), GA ≤ 14% and HbA1c > 5.7% (group 3), and GA ≤ 14% and HbA1c ≤ 5.7% (group 4). We used stepwise multivariable logistic regression analysis to study the inconsistency of HbA1c and GA. Furthermore, we explored their association using multiple linear regression (MLR), random forest regression (RFR), and 3 blended models. Finally, we performed sensitivity analyses by changing the thresholds of HbA1c (6.5%) and GA (12% or 16%). ResultsThere were 934 participants in group 1, 86 in group 2, 964 in group 3, and 1,430 in group 4. Age, high-density lipoprotein-cholesterol concentration, and red blood cell count were associated with the discordance in HbA1c and GA values. We constructed an RFR model that included MLR predictions as independent variables and could explain 97.80% of the variance in HbA1c in the training set, and 91.65% in the cross-validation set. Our results remained robust in 3 sensitivity analyses. ConclusionsHbA1c and GA values are inconsistent in the population we studied. A model that blends MLR and RFR can be used to correct HbA1c values when conflicting HbA1c and GA values are encountered in patients.