Implementation of a telephone-based secondary preventive intervention after acute coronary syndrome (ACS): participation rate, reasons for non-participation and 1-year survival

Background: Acute coronary syndrome (ACS) is a major cause of death from a non-communicable disease. Secondary prevention is effective for reducing morbidity and mortality, but evidence-based targets are seldom reached and new interventional methods are needed. The present study is a feasibility study of a telephone-based secondary preventive programme in an unselected ACS cohort. Methods: The NAILED (Nurse-based Age-independent Intervention to Limit Evolution of Disease) ACS trial is a prospective randomized controlled trial. All eligible patients admitted for ACS were randomized to usual follow-up by a general practitioner or telephone follow-up by study nurses. The intervention was made by continuous telephone contact, with counseling on healthy living and titration of medicines to reach target values for blood pressure and blood lipids. Exclusion criteria were limited to physical inability to follow the study design or participation in another study. Results: A total of 907 patients were assessed for inclusion. Of these, 661 (72.9 %) were included and randomized, 100 (11 %) declined participation, and 146 (16.1 %) were excluded. The main reasons for exclusion were participation in another trial, dementia, and advanced disease. "Excluded" and "declining" patients were significantly older with more co-morbidity, decreased functional status, and had more seldom received education above compulsory school level than "included" patients. Non-participants had a higher 1-year mortality than participants. Conclusions: Nurse-led telephone-based follow-up after ACS can be applied to a large proportion in an unselected clinical setting. Reasons for non-participation, which were associated with increased mortality, include older age, multiple co-morbidities, decreased functional status and low level of education.