Serum Cholesterol, Lifestyle, Working Capacity and Quality of Life in Patients with Coronary Artery Disease. Experiences from a Hospital-based Secondary Prevention Programme

Abstract: Coronary artery diseases (CAD) are main causes of morbidity and hospitalisation in western countries and CAD patients are at considerable risk of suffering further cardiac events. The development and evaluation of secondary prevention programmes therefore an important task. This thesis includes investigations on CAD patients admitted to a secondary prevention programme at Malmö University Hospital, Malmö, Sweden. Four weeks after discharge from the hospital, consecutive male and female patients aged 50 – 70 years with acute myocardial infarction (AMI) or treated with coronary artery bypass grafting (CABG) surgery were randomised to a hospital organised preventive intervention or to usual follow-up at their general practitioners. In the three studies using this randomised design, 87 (study II), 90 (study IV), and 106 (study V) intervention patients were available for evaluation. In addition, without randomisation, lipid levels at four weeks after the event was compared with levels estimated within 24 hours after onset of symptoms in 141 AMI patients (study I), and quality of life (QL) were estimated by questionnaire at one month and at one year after the event in 266 AMI, 94 CABG, and 16 percutaneous transluminal coronary angioplasty (PTCA) patients (study III). The prevention programme was effective in improving food habits but showed no impact on smoking habits or physical exercise in AMI patients (study II). The intervention also did not show any significant improvement in working capacity in AMI and CABG patients. However, working capacity improved in both intervention and reference CABG patients, most probably due to improved coronary circulation from the surgery (study IV). Cholesterol levels decreased significantly in AMI and CABG intervention patients as compared to the corresponding reference patients. This difference most likely was due to a higher frequency of lipid lowering drugs used in the intervention patients (study V). The prevention programme also decreased body mass index significantly in AMI but not in CABG patients (study V). In AMI patients reserving thrombolysis, cholesterol levels estimated within 24 hours after onset of symptoms and at four weeks after the event were virtually equal. In AMI patients not receiving thrombolysis, the lipid estimates from four weeks after the event were slightly, but significantly, above the within 24 hours from onset of symptoms estimates (study I). One month after the event, both somatic and psychological aspects of QL were negatively affected in AMI and CABG patients com--pared to population controls. One year after the event, patients differed from controls mainly in somatic symptoms (study III). Thus, the intervention programme was most successful in affecting lipid levels and food habits in AMI patients. QL was considerably affected in patients following an cardiac event, especially during the initial recovery phase. In addition, in patients receiving thrombolysis, cholesterol levels estimated four weeks after an AMI are reasonably valid estimates of baseline values and may be used to decide about lipid lowering interventions.