Diabetes guidance 1766.pdf - East Cheshire NHS Trust

HbA1c as a Diagnostic Test for DiabetesWhile fasting glucose is still recommended as the initial screening test for suspected diabetes, WHO (2011) hasnow recommended that HbA1c can be used as a diagnostic test for diabetes in most situations, as outlinedin the following paragraph. The main exceptions are rapid onset diabetes (as HbA1c reflects glycaemiaover the preceding 2–3 months) and some genetic, haematological and other disorders; in particularhaemoglobinopathies, anaemia and other diseases associated with changes in red cell turnover (e.g. malaria,drug-induced haemolysis) or glycation rates (e.g. chronic renal disease). In these situations, HbA1c is notrecommended as the sole test to diagnose diabetes.An HbA1c of ≥48 mmol/mol is recommended as the cut point for diagnosing diabetes.An HbA1c level ≥48 mmol/mol can therefore be used to confirm a diagnosis of diabetes in an asymptomaticindividual with a fasting glucose ≥7.0 mmol/L or random glucose ≥11.1 mmol/L, thus precluding the needfor a repeat glucose measurement or oral glucose tolerance test. However, an HbA1c value