Effect of Local Medical Opinion Leaders on Quality of Care for Acute Myocardial Infarction

Abstract

Context.— The effectiveness of recruiting local medical opinion leaders to improve quality of care is poorly understood. Objective.— To evaluate a guideline-implementation intervention of clinician education by local opinion leaders and performance feedback to (1) increase use of lifesaving drugs (aspirin and thrombolytics in eligible elderly patients, β-blockers in all eligible patients) for acute myocardial infarction (AMI), and (2) decrease use of a potentially harmful therapy (prophylactic lidocaine). Design.— Randomized controlled trial with hospital as the unit of randomization, intervention, and analysis. Setting.— Thirty-seven community hospitals in Minnesota. Patients.— All patients with AMI admitted to study hospitals over 10 months before (1992-1993, N=2409) or after (1995-1996, N=2938) the intervention. Intervention.— Using a validated survey, we identified opinion leaders at 20 experimental hospitals who influenced peers through small and large group discussions, informal consultations, and revisions of protocols and clinical pathways. They focused on (1) evidence (drug efficacy), (2) comparative performance, and (3) barriers to change. Control hospitals received mailed performance feedback. Main Outcome Measures.— Hospital-specific changes before and after the intervention in the proportion of eligible patients receiving each study drug. Results.— Among experimental hospitals, the median change in the proportion of eligible elderly patients receiving aspirin was +0.13 (17% increase from 0.77 at baseline), compared with a change of −0.03 at control hospitals (P=.04). For β-blockers, the respective changes were +0.31 (63% increase from 0.49 at baseline) vs +0.18 (30% increase from baseline) for controls (P=.02). Lidocaine use declined by about 50% in both groups. The intervention did not increase thrombolysis in the elderly (from 0.73 at baseline), but nearly two thirds of eligible nonrecipients were older than 85 years, had severe comorbidities, or presented after at least 6 hours. Conclusions.— Working with opinion leaders and providing performance feedback can accelerate adoption of some beneficial AMI therapies (eg, aspirin, β-blockers). Secular changes in knowledge and hospital protocols may extinguish outdated practices (eg, prophylactic lidocaine). However, it is more difficult to increase use of effective but riskier treatments (eg, thrombolysis) for frail elderly patients. THE INFLUENCE OF local medical opinion leaders in the diffusion and adoption of new medical treatments has been recognized for almost half a century.1,2 Opinion leaders are not necessarily innovators or authority figures, but are trusted by their colleagues to evaluate new information and assess the value of new medical practices in the context of local group norms3; are approached frequently for clinical advice; have good listening skills4; and are perceived as clinically competent and caring.5 Many researchers and policymakers advocate recruiting opinion leaders in ongoing quality improvement efforts, in part because of the potential efficiency of capitalizing on local volunteers skilled in changing practice patterns.6 Yet, evidence supporting such interventions is limited,4,7,8 including only 1 randomized controlled trial (RCT) that enlisted local opinion leaders to reduce unnecessary cesarean deliveries in Canada.4 No well-controlled study has examined the effectiveness of recruiting opinion leaders to influence the adoption of underused, lifesaving interventions for major acute illnesses, such as acute myocardial infarction (AMI). The selection of treatments for AMI patients represents one of the most critical decisions in medical practice.9 Coronary heart disease is the leading cause of death in the United States.10 Large RCTs and national guidelines strongly support the early administration of aspirin, β-blockers, and thrombolytic agents for AMI because they substantially reduce mortality and morbidity in eligible patients.9,11- 18 However, a meta-analysis of 14 RCTs of lidocaine prophylaxis to reduce ventricular fibrillation during AMI indicates that this practice may lead to increased mortality, especially in uncomplicated MI.19 The national guidelines also recommend avoidance of lidocaine prophylaxis.17,18 Yet, recent studies of actual practice have found substantial nonadherence to these recommendations, resulting in potentially avoidable morbidity and mortality.20,21 Our previous report of baseline data at the 37 hospitals participating in this study indicated that only 53% of eligible patients received β-blockers.21 Although aspirin use and thrombolysis were high (87% and 81%, respectively) among eligible nonelderly patients, only 76% and 69% of eligible elderly patients (aged 65 years or older) received aspirin and thrombolytic agents, respectively. About 20% of patients received prophylactic lidocaine. In this article we report the results of a large statewide RCT that combined identification and involvement of local opinion leaders with performance feedback to improve quality of care for AMI. Specifically, we sought to increase adherence to the national (American College of Cardiology/American Heart Association [ACC/AHA]) guidelines recommending (1) increased use of highly effective drugs for eligible AMI patients, ie, β-blockers in all patients and aspirin and thrombolysis in the elderly, and (2) reduced use of an ineffective treatment, ie, prophylactic lidocaine.