The treatment and prevention of coronary heart disease in Canada: Do olderpatients receive efficacious therapies?

OBJECTIVES: To review the evidence for clinical efficacy and cost-effective ness of proven medications in the treatment and prevention of myocardial in farction (MI) in older patients; to summarize Canadian data on treatment pa tterns and clinical outcomes for younger and older patients with coronary h eart disease; to explore the reasons for gaps between best care, based on t he evidence of efficacy from trials, and usual care, based on the populatio n effectiveness audits; and to explore potential approaches to closing the care gaps. DESIGN: Review of the recent clinical trial literature on the management of MI, highlighting results in older patients. Review of medication utilizati on and outcomes data from a series of large, consecutively enrolled patient cohorts with acute MI (N = 7070) in a variety of cardiac care settings (10 centers in five Canadian provinces, including university-based teaching ho spitals, community hospitals, cardiologist and family physician out-patient clinics) from 1987 to 1996. RESULTS: There is no qualitative interaction of cardiac therapies: thrombol ytics, beta-blockers, acetylsalicylic acid (ASA), and statins are efficacio us in all clinically relevant patient subgroups, including older people. Ho wever, there are consistent gaps between usual care and best care, particul arly among older patients (in whom there is also a concomitantly higher mor tality risk). Repeated multivariate analyses confirm older age to be an ind ependent contributor to increased risk. Use of efficacious medications is, in contrast, consistently associated with increased survival. Analysis of t emporal trends suggests beneficial changes in practice patterns and outcome s are possible to achieve. However, "best care" has not been rapidly or com pletely achieved. Review of strategies to close these care gaps suggests th at audit and feedback, critical pathways, and multifactorial interventions involving patients and other members of the healthcare team as well as phys icians may be the most efficacious strategies for change. CONCLUSIONS: Despite equal or enhanced efficacy, there is consistently less prescription of proven drugs among older cardiac patients. These care patt erns may contribute to their enhanced risk. The causes underlying these pra ctice patterns are complex, and their population impact may be undervalued by clinicians and managers. Improvement of these patterns is difficult, but ultimately it would be beneficial for this presently disadvantaged, readil y identified, high risk patient population.