HbA(1c) for Diabetes Screening in Acute Coronary Syndrome: time for a reappraisal of the guidelines?

OBJECTIVE: Diabetes is highly prevalent in individuals with acute coronary syndrome (ACS). Current NICE guidelines recommend diabetes screening of hyperglycaemic patients using a fasting plasma glucose after 4 days from admission. In 2012 the World Health Organisation (WHO) approved the use of HbA(1c) in the diagnosis and targeted screening for type 2 diabetes. We introduced a service improvement project using HbA(1c) for diabetes screening in patients with no previous diagnosis of diabetes admitted with ACS regardless of glycaemic state. METHOD: An initial retrospective audit utilised 21 months of data from the MINAP database to identify patients meeting current NICE criteria for diabetes screening. A prospective service improvement project was undertaken over a 4 month period using HbA(1c) as a universal screening test to categorise ACS patients based on WHO criteria. RESULTS: The retrospective audit identified 93 of 420 (22%) patients with pre-existing diabetes and 8 of the remaining 327 (2.4%) were hyperglycaemic, thus meeting NICE criteria for diabetes screening. In the service improvement project 2/49 patients (4%) met NICE criteria for diabetes screening. Twenty six of these 49 patients had a HbA(1c) test on admission and 17/26 (65.4%) were classified as probable diabetes or high risk. CONCLUSION: A significant proportion of ACS patients have diabetes, which may be undetected by current NICE criteria. Universal HbA(1c) testing offers utility as a simple and effective screening test for diabetes in the ACS population.