Hemoglobina glicosilada A1c vs. glucemia plasmática en ayunas de pacientes ambulatorios de un laboratorio médico

Abstract

Objective Comparing haemoglobin A glycosylate (HbA1c) at different cutoff points for blood glucose measurement to the fasting plasma glucose (FPG) test in outpatients visiting a medical laboratory in the city of Medellin between March and April 2010. Methods 1,016 blood samples were studied from patients who had been referred to a medical laboratory. Agreement was obtained between tests (Kappa index); sensitivity and specifi city were calculated. Different cutoff points for the HbA1c test were also evaluated with the ROC curve. Spearman correlation was used to establish association between FPG and Hb A1c. Results Average HbA1c was 5.7 %±0.8 and average FPG was 96 mg/dL±26.1; this was higher in men (99.04±32.7). 75.4 % of the samples came within the normal range for diagnosing diabetes with the FPG test, compared to 51.4 % with the HbA1c test. The cutoff point where combined sensitivity and specifi city presented the best HbA1c value in this study group was 6.2 %. Discussion The HbA1c test had high sensitivity and specifi city values, so its routine use in diagnosing diabetes mellitus could contribute towards active and early detection of cases to ensure better control of risk factors.