Analysis of the Combined Screening Value of Glycated Hemoglobin and Fasting Blood Glucose in Community-Based Geriatric Health Checkups

Abstract

To evaluate the value of glycated hemoglobin (HbA1c) and fasting plasma glucose (FPG) for diabetes screening in community-dwelling elderly population, both individually and collectively, and thereby providing evidence for optimizing early diabetes screening strategies in community health checkups, 200 elderly residents aged ≥65 years who underwent annual health examinations at the Southeast Community Health Service Center of Deyang City, Sichuan Province, China from January to December 2025 were enrolled. All participants underwent HbA1c and FPG testing. Using the oral glucose tolerance test (OGTT-2hPG ≥ 11.1 mmol/L) as the golden standard for diabetes diagnosis, we calculated and compared the sensitivity, specificity, Youden index, and area under the receiver operating characteristic curve (AUC) for FPG, HbA1c, and their combined screening. Results showed that among the 200 subjects, the diabetes detection rate via OGTT was 16.5% (33 cases), and HbA1c screening (cutoff 6.2%) demonstrated a sensitivity of 81.8%, significantly higher than FPG screening (cutoff 6.1 mmol/L) at 66.7%, but its specificity (89.8%) was slightly lower than FPG (94.0%). Among them, the series combination yielded the highest specificity (98.2%), while the parallel combination achieved the highest sensitivity (93.9%). The AUC was 0.927, indicating significantly superior screening performance compared to single tests. The Youden index suggested the parallel combination as the optimal strategy. In conclusion, in community-based geriatric health examinations, glycated hemoglobin could serve as an effective diabetes screening indicator. The parallel combination of glycated hemoglobin and fasting plasma glucose might significantly enhance screening sensitivity, reduce missed diagnoses, and would be suitable for large-scale screening in community-dwelling elderly population.