Underuse of Evidence-Based Therapies
Cardiovascular specialists have been leaders in medicine because of our willingness to study major clinical issues by means of randomized clinical trials. Consequently, the evidence supporting many cardiovascular treatments is substantial, especially when the results of multiple large clinical trials are consistent in showing strong benefits. Cardiovascular professional societies also have been at the forefront in forging consensus among clinical experts and codifying best practice into practice guidelines. It is reasonable to expect that a treatment demonstrated to be effective in clinical trials and strongly endorsed by professional guidelines will be adopted by practicing physicians and consistently used in day-to-day patient care.
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Angiotensin-converting enzyme (ACE) inhibitors have followed this pathway of building evidence and professional consensus. Many randomized clinical trials have clearly shown that ACE inhibitors reduce mortality and morbidity rates among patients with heart failure and left ventricular systolic dysfunction. Pooled data from 5 large trials1 showed the odds of death of patients randomized to ACE inhibitors were reduced by 26% compared with placebo, translating into roughly 6 fewer deaths per 100 patients treated. The economic outcomes also are favorable because much of the cost of prescribing ACE inhibitors for heart failure is recouped by the reduced need for hospital admissions. Consequently, the use of ACE inhibitors for heart failure is quite cost-effective.2 The American College of Cardiology/American Heart Association Guidelines Committee has weighed the evidence and given ACE inhibitors for treatment of heart failure a Class I recommendation.3 Indeed, use of ACE inhibitors is so well accepted that it is part of the quality-of-care clinical performance measure for heart failure. There is little, if any, controversy that ACE inhibitors should be generally prescribed for patients with heart failure due to systolic dysfunction.
Use of ACE inhibitors increased progressively for heart failure through the early 1990s,4 but growth in use has stalled more recently, and a substantial number of patients with heart failure still do not receive ACE inhibitors. The data reported by Masoudi and associates5 in this issue of Circulation show a stubborn, persistent gap between ideal practice and actual use of ACE inhibitors for heart failure. These investigators found that between 1998 and 2001, only 68% of patients 65 years of age and older with heart failure, systolic dysfunction, and no contraindications to treatment received an ACE inhibitor. This percentage rose only to 76% of patients when either ACE inhibitor or angiotensin receptor blocker (ARB) use was counted. The percentage of patients receiving ACE inhibitors or ARBs was below 80% in all but 3 of the 55 subgroups examined by Masoudi and associates. The investigators found little explanation for this persistent and vexing gap between actual and ideal performance, inasmuch as the only strong predictor of ACE inhibitor use versus nonuse was the presence of preexisting renal dysfunction. The latest national report card on this important aspect of heart failure treatment shows a “D+” for ACE inhibitor use (68%), rising only to a “C” (76%) if extra credit is given for ARB use. Should we accept these grades?
Closing the Gap
Perhaps the most optimistic interpretation of the data reported by Masoudi and associates is that evidence from clinical trials, by itself, will only go so far in changing clinical practice.6 Evidence may be necessary to alter the knowledge and attitudes of physicians about treatment, but this may not be sufficient to change their management consistently. To close the gap between actual and ideal performance, additional, specific measures are probably needed. A variety of active interventions have been shown to improve use of evidence-based therapies. Masoudi and associates did not report any data on use of measures within the hospitals or physician practices that might improve quality of care, so there may be an opportunity to adopt such measures more widely. Reminder systems for physicians, either simple chart-based measures or more sophisticated computerized approaches, can be quite effective in improving use of medications when physicians agree that the medication is effective. Critical pathways, care maps, and other structured approaches to quality improvement also may work well within hospitals to increase adherence to evidence-based practice guidelines. Reorganization of care by use of heart failure care teams or nurse facilitators may be even more effective,7 but these approaches require a much greater commitment of resources. Nevertheless, multidisciplinary approaches are particularly attractive in the care of patients with chronic diseases such as heart failure, because management of multiple factors, including adherence to diet and medication recommendations, is needed for successful outcomes. The structure of our medical care system also may contribute to the gap between actual and ideal clinical management; paying for innovative practice improvement programs has been difficult because they are not readily reimbursed in the fee-for-service model (although they may be well suited to prepaid integrated healthcare systems).
We have paid a lot of attention to translation of novel therapies from the basic laboratory to proof of efficacy in clinical trials, yet we’ve not paid enough attention to the final steps of learning how to best deliver consistent, high-quality care. With more attention to the nitty-gritty details of practice improvement, the grade for ACE inhibitor use in patients with heart failure could (and should) be raised to an “A” on the next report card.
The opinions expressed in this editorial are not necessarily those of the editors or of the American Heart Association.
Hunt SA, Baker DW, Chin MH, et al. ACC/AHA guidelines for the evaluation and management of chronic heart failure in the adult: executive summary: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Committee to Revise the 1995 Guidelines for the Evaluation and Management of Heart Failure): International Society for Heart and Lung Transplantation, Heart Failure Society of America. Circulation. 2001; 104: 2996–3007.
Masoudi FA, Rathore SS, Wang Y, et al. National patterns of use and effectiveness of angiotensin converting enzyme inhibitors in older patients with heart failure and left ventricular systolic dysfunction. Circulation. 2004; 110: 724–731.