Point‐of‐care Glucose and Hemoglobin A1c in Emergency Department Patients without Known Diabetes: Implications for Opportunistic Screening

Abstract

Objectives: The objectives were to evaluate the correlation between random glucose and hemoglobin A1c (HbA1c) in emergency department (ED) patients without known diabetes and to determine the ability of diabetes screening in the ED to predict outpatient diabetes.Methods: This was a cross-sectional study at an urban academic ED. The authors enrolled consecutive adult patients without known diabetes during eight 24-hour periods. Point-of-care (POC) random capillary glucose and HbA1c levels were tested, as well as laboratory HbA1c in a subset of patients. Participants with HbA1c ‡ 6.1% were scheduled for oral glucose tolerance test (OGTT). Results:The 265 enrolled patients were 47% female and 80% white, with a median age of 42 years. Median glucose and HbA1c levels were 93 mg ⁄ dL (interquartile range [IQR] = 82-108) and 5.8% (IQR = 5.5-6.2), respectively. The correlation between POC and laboratory HbA1c was r = 0.96, with mean difference 0.33% (95% confidence interval [CI] = 0.27% to 0.39%). Glucose threshold ‡ 120 mg ⁄ dL had 89% specificity and 26% sensitivity for predicting the 76 (29%) patients with abnormal HbA1c; ‡ 140 mg ⁄ dL had 98% specificity and 14% sensitivity. The correlation between random glucose and HbA1c was moderate (r = 0.60) and was affected by age, gender, prandial status, corticosteroid use, and current injury. Only 38% of participants with abnormal HbA1c returned for OGTTs; 38% had diabetes, 34% had impaired fasting glucose ⁄ impaired glucose tolerance, and 28% had normal glucose tolerance.Conclusions: ED patients have a high prevalence of undiagnosed diabetes. Although screening with POC random glucose and HbA1c is promising, improvement in follow-up with confirmatory testing and initiation of treatment is needed before opportunistic ED screening can be recommended.

Performance of point-of-care HbA1ctest devices: implications for use in clinical practice – a systematic review and meta-analysis

“…Sixteen studies reported receiving funding from the POC device manufacturers [7,9,27,30,35,36,39,41,47,50,51,56,58,59,65,70]. In 18 of the included studies, the instrument was provided free of charge by the manufacturers [3,7,9,24,27,31,36,38,39,44,50,53,54,56,59,65,69,70].…”

“…In 18 of the included studies, the instrument was provided free of charge by the manufacturers [3,7,9,24,27,31,36,38,39,44,50,53,54,56,59,65,69,70]. In eight studies, it was unclear what laboratory methodology was used in the comparator method [22,33,35,41,43,51,61,74]. Another seven studies did not use a wide range of HbA 1c concentrations to assess mean bias across all HbA 1c concentrations [24,25,41,50,57,71,73].…”

“…Another seven studies did not use a wide range of HbA 1c concentrations to assess mean bias across all HbA 1c concentrations [24,25,41,50,57,71,73]. Nine studies used an NGSPor IFCC-certified laboratory for the comparator method [3,7,29,41,50,54,56,59,60].…”

Can Hemoglobin A1c Testing in Hospital Settings Help the Early Identification of Diabetes?

“…It is a reliable, rapid test that does not require the patient to be fasting. 9 When glucose reacts with hemoglobin, glycated (or glycosylated) hemoglobin is formed. 9 The HbA 1c test reflects the average level of glucose the red blood cell has been exposed to over its 120-day life span.…”

Public Health Education for Emergency Medicine Residents

“…1,2 Emergency departments have proved to be effective settings for disease surveillance and for a variety of screening and intervention programs for conditions such as HIV, falls, suicide, intimate partner violence, tobacco addiction, alcohol and drug abuse, chronic disease and injury [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17] . These public health-relevant activities, surveillance, screening, and intervention, were the subject of a 2009 conference convened by emergency physicians for emergency physicians, policymakers, and educators.…”