Non-diabetic hyperglycaemia correlates with angiographic coronary artery disease prevalence and severity

AimThe role of glycaemia as a coronary artery disease (CAD) risk factor is controversial, and the optimal glucose level is still a matter of debate. For this reason, we assessed the prevalence and severity of angiographic CAD across hyperglycaemia categories and in relation to haemoglobin A_1c (HbA_1c) levels.MethodsWe studied 273 consecutive patients without prior revascularization undergoing coronary angiography for suspected ischaemic pain. CAD severity was assessed using three angiographic scores: the Gensini's score; extent score; and arbitrary index. Patients were grouped, according to 2003 American Diabetes Association criteria, into those with normal fasting glucose (NFG), impaired fasting glucose (IFG) and diabetes mellitus (DM).ResultsCAD prevalence was 2.5-fold higher in both the IFG and DM groups compared with the NFG group. Deterioration of glycaemic profile was a multivariate predictor of angiographic CAD severity (extent score: P = 0.027; arbitrary index: P = 0.007). HbA_1c levels were significantly higher among CAD patients (P = 0.016) and in those with two or more diseased vessels (P = 0.023) compared with the non-CAD group. HbA_1c levels remained predictive of CAD prevalence even after adjusting for conventional risk factors, including DM (adjusted OR: 1.853; 95% CI: 1.269–2.704).ConclusionNon-diabetic hyperglycaemia, assessed either categorically by fasting glucose categories or continuously by HbA_1c levels, correlates with the poorest angiographic outcomes.