Diabetes case finding in the emergency department, using HbA1c: an opportunity to improve diabetes detection, prevention, and care

Abstract

ObjectiveWe assessed the efficacy of routine glycated hemoglobin (HbA1c) testing to detect undiagnosed diabetes and prediabetes in an urban Australian public hospital emergency department (ED) located in an area of high diabetes prevalence.MethodsOver 6 weeks, all patients undergoing blood sampling in the ED had their random blood glucose measured. If ≥5.5 mmol/L (99 mg/dL), HbA1c was measured on the same sample. HbA1c levels ≥6.5% (48 mmol/mol) and 5.7–6.4% (39–46 mmol/mol) were diagnostic of diabetes and prediabetes, respectively. Hospital records were reviewed to identify patients with previously diagnosed diabetes.ResultsAmong 4580 presentations, 2652 had blood sampled of which 1267 samples had HbA1c measured. Of these, 487 (38.4%) had diabetes (either HbA1c≥6.5% or a prior diagnosis), and a further 347 (27.4%) had prediabetes. Among those with diabetes, 32.2% were previously undiagnosed.ConclusionsRoutine HbA1c testing in the ED identifies a large number of people with undiagnosed diabetes and prediabetes, and provides an opportunity to improve their care.

In-hospital screening for diabetes mellitus with HbA1c in an internal medicine department was not useful; a prospective pilot study

“…Although categorical agreement (no diabetes, prediabetes, diabetes) between morning plasma glucose and HbA1c was low in our study, most patients (92%) with a morning glucose <125 mg/dl had an HbA1c value <6.5%. Other studies have also described the use of fasting or random plasma glucose as a first step for screening inpatients for diabetes mellitus [10,[27][28][29]. Although the requirement of fasting for several hours (typically 8 hours) may be impractical in acutely ill hospitalized patients, in our setting we found that morning blood sampling results in most samples being fasting.…”

“…An informed consent was not required as this was a non-interventional study (the criteria used for obtaining HbA1c are in agreement with the indications for screening for diabetes mellitus according to standard guidelines [3]). Furthermore, many prior studies have validated the use of HbA1c measurement among hospitalized patients [6,[10][11][12][13][14][15][16][17][18]. Patients were informed about the results and if diabetes was detected were referred to the diabetology unit.…”

“…The following patients were excluded from our screening protocol: 1) Patients with known diabetes mellitus. 2) Patients without a prior diagnosis of diabetes mellitus but a low admission glucose (<100 mg/dl), as such patients are unlikely to have diabetes mellitus [10]. Measurement of glucose at admission was not required but represents routine practice in our hospital.…”

“…In contrast to glucose-based methods, HbA1c is not substantially affected by acute illness [3,9]. Several previous studies have screened acute medical admissions or patients presenting to the emergency department with HbA1c to identify patients with undiagnosed or poorly controlled diabetes mellitus and most studies have demonstrated a high prevalence of undiagnosed diabetes mellitus [6,[10][11][12][13][14][15][16][17][18]. A disadvantage of HbA1c is that some conditions may interfere with the measurement (e.g.…”

Routine glucose assessment in the emergency department for detecting unrecognised diabetes: a cluster randomised trial

“…Another Australian study, in which HbA 1c was also assessed in patients with at least 5.5 mmol/L blood glucose, found that 38% of ED patients either had known diabetes or met the HbA 1c criterion for diabetes; diabetes had not previously been recognised in one-third of these cases. 15 Neither study examined documentation of diabetes or initiation of treatment. In a third Australian study, HbA 1c screening indicated that 5% of hospital inpatients aged 55 years or more had unrecognised diabetes.…”