Secondary prevention of diabetic patients with coronary artery disease in cardiac rehabilitation: risk factors, treatment and target level attainment

Introduction: Diabetic patients who have suffered from an acute coronary syndrome (ACS) or have had coronary artery bypass graft (CABG) surgery are at very high risk of recurrent cardiovascular events. Their prognosis, however, can be improved if the target values for blood pressure (BP < 130/80 mmHg) or low density lipoprotein cholesterol [LDL-C<2.6 mmol/L (100 mg/dl), optionally <1.8 mmol/L (70 mg/dl)] are achieved. It is not known what proportion of diabetic patients receives such stringent secondary prevention measures and achieves target level attainment for BP, lipids and glucose in cardiac rehabilitation (CR). Methods: During 2003 to 2005, 11973 diabetic (29.7%) and 28370 non-diabetic patients (70.3%), predominantly after ACS (74 and 80%), were included in a nationwide registry. At entry and at discharge, patient characteristics, pharmacotherapy and blood pressure, lipids and blood glucose were recorded. In a mixed model approach, temporal changes between centres and within centres, respectively, were analysed. Results: At discharge, a lower proportion of diabetic patients achieved normalisation of BP (in 2005: <140/90 mmHg: 78.4 vs. 82.9% in non-diabetic patients, p<0.001) or <130/80 mmHg (45.5 vs. 49.8%), respectively. LDL-C<2.6 mmol/L was more frequently attained in diabetic patients (68.2 vs. 66.5%), as was LDL-C<1.8 mmol/L (28.8 vs. 23.0%). Fasting blood glucose was not changed during the observation period, as at discharge almost a quarter of all diabetic patients exceeded the threshold value of 7.0 mmol/L (126 mg/dl). In 2005 at discharge, statin therapy was administered in 93% in both diabetics and non-diabetics, acetylic salicylic acid in 79% in diabetics vs. 80% in non-diabetic patients (clopidogrel: 41 vs. 45%). Conclusion: Generally there is room for improvement in the management of cardiac risk factors for both patients groups. In diabetic patients in CR at high risk for recurrent cardiac events, in recent years an improvement of the lipid profile has been observed. Hypertension and glycaemia are still not optimally addressed.