Reactive Hyperglycaemia Connected with Low Glycated Haemoglobin – Risk Factor for Cardiovascular Adverse Events

Abstract

Introduction: Concomitance of glucose metabolism disturbances and ischemic heart disease is well known and connected to several times higher incidence of cardiovascular events resulted from atherosclerosis. Aim of this study was to assess impact of reactive hyperglycaemia accompanying chronic and not always optimally treated hyperglycaemia assessed with glycated haemoglobin level on cardiovascular prognosis among patient hospitalised in the course of acute myocardial infarction. Methods: 92 patients diagnosed with ST – segment elevation myocardial infarction (STEMI) qualified to primary percutaneous coronary intervention (pPCI) was included in the study. Study population was divided into subgroups, depending glucose level on admission (reactive hyperglycaemia) and HbA1c concentration: subgroup A (HbA1c <6.5%, Glc<7.8 mmol/l: n = 37; 40,2%), subgroup B (HbA1c <6.5%, Glc ≥.,8 mmol/l: n = 27; 29,3%), subgroup C (HbA1c ≥6.5%, Glc ≥7.8 mmol/l: n = 20; 21,7%) and subgroup D (HbA1c ≥6.5% Glc<7.8 mmol/l: n = 8; 8.7%). Level of myocardium damage was assessed on the basis of concentration of myocardial necrosis enzymes: creatine kinase (CK) and creatine kinase MB fraction (CK-MB) in the 0 and 90th minute and thereafter 8, 16, 24 and 48 hours after hospital admission and also echocardiographic examination. Prognosis in long and short term observation was assessed by major adverse cardiovascular events (MACE) such as death, myocardial infarction, stroke, heart failure requiring hospitalisation and repeated revascularisation and level of glucose metabolism disturbances in intrahospital phase, 4 months and 4 years follow up observation. Results: Results in study population revealed significant change of average value of creatine kinase (p<0,001) and its MB fraction (p<0,001) during first 48 hours of hospitalisation in particular subgroups of patients. Mean values of CK and CK-MB assessed in subsequent hours of hospitalisation (1,5, 8, 16 and 48 hours) were significantly higher in subgroup B (CKp=0,034 and CK-MB p=0,01, respectively). It means that area under curve was significantly higher for subgroup B. In 4 months and 4 year follow up observation, statistically significant difference in frequency of MACE in particular subgroups of patients has been shown (p=0,016; p=0,01). Conclusions: Patients with STEMI undergoing pPCI, who were diagnosed with disturbed carbohydrate metabolism, have inferior clinical outcomes in long term follow up observation. Noticeable difference was observed particularly in subgroup B (HbA1c <6.5%, Glc ≥7.8 mmol/l).