Concordance and Associated Factors in Diagnostic Criteria for Prediabetes and Diabetes: An Analysis of Fasting Glucose, Postprandial Glucose, and Glycated Hemoglobin

Background: Type 2 diabetes mellitus (T2DM) and prediabetes are rising chronic health conditions globally. Early and accurate identification of these disorders is crucial for effective prevention and management. The objective was to evaluate the concordance and associated factors of prediabetes and diabetes based on fasting glucose (FG), postprandial glucose (PPG), and glycated hemoglobin (HbA1c). Methods: Primary analysis was conducted on patients from a polyclinic located in Lima, Peru. Prevalences were assessed, concordance was evaluated through the kappa index, and multivariable analyses were performed to identify associated factors for each. Results: A total of 624 participants were included. Isolated values of FG, PPG, and HbA1c for prediabetes accounted for 7.1%, 10.6%, and 5% of cases, respectively, while the intersection of all three accounted for 39.7% of the total. For T2DM, isolated values were represented in 14.5%, 23.2%, and 8.7% of cases, respectively, while the intersection of all three accounted for 44.9%. The concordance between FG and PPG was 0.6970 (P < 0.001), between FG and HbA1c was 0.6163 (P < 0.001), and between PPG and HbA1c was 0.6903 (P < 0.001). Significant associations were found with factors such as gender, age, family history of T2DM, alcohol consumption, and hypertension. Conclusions: The results revealed that PPG detected more cases in isolation, followed by FG and HbA1c. Comparison with previous studies showed variations in prevalence, underscoring the importance of considering multiple criteria in diagnosis.