Commentary

The study by Murchie et al found lower death rates after 4 years in patients randomised to structured care delivered by nurses. Although the control group was receiving much the same treatment as the intervention group by the end of the study, the results after 1 year showed that the 2 groups differed in treatments received. Thus a causal pathway for a reduction in mortality is plausible. The finding of improved outcome has face validity.

A previous systematic review of trials of disease management pathways for CAD found that they improved the processes of care but failed to detect an effect on morbidity and mortality.¹ This finding was not surprising because most of the included studies were of short duration and small sample size. Efficacy studies showing reductions in mortality from drug interventions require much larger sample sizes. Even when the implementation studies were combined in a meta-analysis, the power was insufficient to show an effect on outcome. It is reassuring that with longer follow up the study by Murchie et al shows the expected reduction in mortality. As the authors point out, the study still had limited power. This probably accounts for the finding that the confidence intervals for a reduction in coronary events were wide and included 1.

What are the practical implications of these findings? They provide evidence for a common sense concept. When effective interventions exist, they should be offered to patients. To achieve this, organised delivery of care is better than disorganised care. Are nurse led clinics the way to go? The care pathway in this study included identification of eligible patients, systems for following them up, patient education and lifestyle advice, and protocol driven medical management. None of these is specific to nurse led clinics. However, a previous trial showed that clinics were more efficient in delivering a similar package than audit/feedback or recall to primary care doctors in delivering care to patients with heart disease.² In the context of British primary care, nurse led clinics are now the reference standard. The model appears to be generalisable to many other healthcare settings, particularly those where multidisciplinary teams deliver care. The onus is on practices or healthcare systems choosing other methods of delivering care to patients with cardiac disease to prove that they can do it as well.