HbA1c screening for new onset diabetes following acute coronary syndrome: is it a worthwhile test in clinical practice?

Abstract

BackgroundDiabetes and pre-diabetes are prevalent in acute coronary syndrome (ACS) and relate to adverse outcomes. This study used HbA1c to screen for degrees of glucose intolerance amongst patients without known diabetes presenting with ACS.MethodsOver a 1-year period (June 2014–2015) consecutive patients admitted to a single centre cardiology unit with an initial diagnosis of ACS without prior diabetes diagnosis were electronically referred to our diabetes team. Patients were screened for the presence of diabetes by use of an initial HbA1c blood test on day 2 or 3 post admission. If abnormal (≥42 mmol/mol; ≥6.0%), patients were invited for a repeat HbA1c at 2 weeks, and if an intermediate result (42–47 mmol/mol; 6.0–6.4%), for an oral glucose tolerance test (OGTT) at 3 months. Patients were diagnosed with Type 2 diabetes if the repeat HbA1c result was high (≥48 mmol/mol; ≥6.5%) or the OGTT at 3 months confirmed the diagnosis. Other data collected included baseline demographics, risk factors and any history of cardiovascular disease. All patients with ACS were stratified according to the diagnosis and subsequent management.ResultsWe screened 399 patients in total. The mean age was 65 ± 14 years, 268 (67%) were men, 290 (73%) were Caucasian, 95 (24%) were South Asian and 14 (4%) were Afro-Caribbean ethnicity. Of all patients, 57 (14.3%) were diagnosed as pre-diabetes and 43 (10.8%) newly diagnosed diabetes. During the study 28 (7%) patients could not be classified; 6 (1.5%) patients died during the study and 22 (5.5%) patients were missing either initial or repeat HbA1c and were subsequently lost to follow up. Of the baseline variables assessed, there were significantly more patients of South Asian ethnicity in the diabetes group compared to the normal group (42 vs 20%; p = 0.003). There was no difference in detection rates in patients with more severe ACS requiring percutaneous or cardiac surgical intervention.ConclusionsThe use of a simple HbA1c screening method in clinical practice can detect new onset diabetes in approximately 1 in 10 high-risk post ACS patients.

The Impact of Glyco-Metabolic Status in Patients Treated for Acute Coronary Syndrome

“…Similar data have been reported by Arnold and his coworkers [10% prevalence of newly diagnosed diabetes in patients with acute myocardial infarction (AMI), previously not known to have diabetes]. [3] Stress hyperglycemia is present in one of four hospitalized patients. In the Study by Gardner et al, stress hyperglycemia was found in 41% of elderly patients with ACS.…”

“…Arnold reported similar data -10% prevalence of T2DM in AMI patients without known diabetes on admission. [3] Maybe the lowest prevalence of NDDM is reported by Chin in an Australian cohort of ACS patients, about 5%. [1] It is evident that there is a significant influence of racial affiliation on the prevalence of diabetes in the general population, and in the cohort of patients with ACS.…”

“…In the same ethnic groups, the concentration of HbA1c is also higher, as compared to Caucasian patients with similar plasma glucose levels. [3] Lugg and coworkers reported a prevalence of pre-diabetes of 14.3% and T2DM…”

“…However, at this moment, we do not have enough evidence to state that the severity and type of acute coronary syndrome affects the incidence of pre-diabetes and diabetes. [3] Stress hyperglycemia is even more important than newly diagnosed diabetes in terms of prognosis in ACS patients. It is reported that one in every four hospitalized critically ill patients has stress hyperglycemia.…”

“…Non-diabetic patients with stress hyperglycemia have 3.9 fold higher risk of death after myocardial infarction in comparison to normoglycaemic non-DM patients. [3,6,7] Having all this in mind, we decided to perform a more comprehensive analysis of our pa-tients' cohort hospitalized and treated for Acute Coronary Syndrome, in terms of incidence of stress hyperglycemia and newly diagnosed diabetes, but also to determine the prognostic impact of glyco-metabolic parameters on short term (in-hospital) clinical outcome in these patients' cohort.…”