Secondary prevention programmes for coronary heart disease: a meta-regression showing the merits of shorter, generalist, primary care-based interventions

Background The aim of this study was to determine which programme characteristics influence the effectiveness of secondary prevention programmes for Coronary Heart Disease. Design The study follows a meta-regression design. Methods We conducted a meta-regression within a systematic review of randomized trials comparing secondary prevention programmes versus usual care. The primary outcome was all-cause mortality. Studies were identified by searching multiple electronic databases, bibliographies of published studies, contact with experts, and references provided by the United States Centers for Medicare and Medicaid Services. Primary authors of all relevant trials were surveyed for detailed information on programme characteristics. Forty-six unique trials were identified (18 821 patients). The pooled all cause mortality risk ratio (RR) for programmes was 0.87 [95% confidence interval (Cl) 0.79-0.97]. Programmes containing less than 10h of patient contact with health professionals reduced all-cause mortality (RR 0.80, 95% Cl 0.68-0.95) as effectively as programmes with more contact time. Programmes provided in general practice settings were effective at reducing all-cause mortality (RR 0.76, 95% Cl 0.63-0.92) and compared favourably with the effectiveness of hospital-based programmes. Other characteristics, including specialist versus generalist provision, did not appreciably impact programme effectiveness. Conclusions Shorter secondary prevention programmes, those based in general practice, and those staffed by generalists are at least as effective in reducing all cause mortality in patients with coronary heart disease as longer programmes, hospital-based programmes, and programmes staffed by specialists.