Heart failure (HF) is among the leading causes of hospitalization in the United States, afflicting more than 5.8 million men and women each year. The disease has been associated with substantial morbidity, mortality, and healthcare expenditures. The 5-year mortality rate for HF has been estimated at more than 50%, and roughly $40 billion is spent annually in costs related to HF. Previous studies have shown that there are gaps, variation, and disparities in the use of evidence-based, guideline-recommended therapies for HF. Regardless of the clinical setting, many eligible HF patients do not receive one or more of the therapies that have been proven to be effective in reducing all-cause mortality in clinical trials and analyses. Non-adherence to recommended HF therapies can significantly reduce quality of life and lifespan in sufferers with the disease.
Examining Benefits of Proven HF Therapies
A study published in the February 21, 2012 Journal of the American Heart Association: Cardiovascular and Cerebrovascular Diseases evaluated the individual and incremental benefits of guideline-recommended therapies. “While certain therapies are recommended for HF patients in national guidelines from the American College of Cardiology and the American Heart Association, our study was the first to examine the specific incremental contribution of each of these therapies in improving survival when combined in a real-world clinical practice,” says Gregg C. Fonarow, MD, who was the lead author on the investigation.
The study by Dr. Fonarow and colleagues utilized a nested case-control design that included HF patients who were enrolled in the Registry to Improve the Use of Evidence-Based Heart Failure Therapies in the Outpatient Setting (IMPROVE HF) cohort. The analysis involved 1,376 patients who died within 24 months; 2,752 patients who survived to 24 months were included in the control group. The key guideline-recommended therapies evaluated were:
Three types of HF medications: β-blockers, aldosterone antagonists, and ACE inhibitors or angiotensin receptor blockers.
Cardiac resynchronization therapy (CRT).
Anticoagulant therapy for atrial fibrillation.
Implantable cardioverter-defibrillators (ICDs).
HF patient education.
Each individual guideline-recommended therapy for HF analyzed in the study was associated with an important survival benefit, with the lone exception being use of aldosterone antagonists (Table 1). The greatest individual benefits were observed with the use of β-blockers and CRT. Use of β-blockers reduced the odds of HF mortality by 58% over 24 months, while CRT use was linked to a 56% reduction in the odds of HF mortality over 24 months. The finding on aldosterone antagonist use contradicted the results of multiple randomized clinical trials that demonstrated efficacy and an association with lower mortality risk. According to Dr. Fonarow, this finding may have resulted from confounding by indication or other forms of observational bias. Alternatively, aldosterone antagonist use may be less effective or less safe as dosed and monitored in actual clinical practice. “More studies of the clinical effectiveness of aldosterone antagonists in HF are needed,” Dr. Fonarow says. “Nevertheless, eligible HF patients should continue to be treated with this evidence-based, guideline-recommended therapy.”
Incremental Improvements in HF Matter
As each guideline-recommended therapy for HF was added in the study, the overall survival rate increased incrementally. When compared with no treatment at all, up to a 90% reduction in mortality rate was observed in 24 months of observation (Table 2). “This is a remarkable improvement in clinical outcome for patients with HF and reduced ejection fraction,” says Dr. Fonarow. It should be noted that the study revealed that there appeared to be a plateau in survival benefit after any four or five guideline-recommended HF therapies were applied. “This may be the result of relatively few patients qualifying for and being treated with all seven of the guideline-recommended therapies we analyzed in the study,” explains Dr. Fonarow. “This potential plateau will require further confirmation in future studies.”
Looking Into the Future of Heart Failure Management
High-quality, patient-centered outcomes research is a national priority, Dr. Fonarow says, and may better inform clinical decision-making in patients with HF. “Our study provides patients, clinicians, purchasers, and policymakers with compelling evidence of the incremental improvements in clinical outcomes for patients with HF that can be achieved with guideline-recommended therapies. The next step is to continue analyzing these data to further assist decision-making processes for patients with HF.”
Previous studies have suggested that as many as 68,000 additional lives could be saved each year in the U.S. by optimally implementing evidence-based therapies for HF. “Our study provides further evidence supporting the clinical effectiveness of guideline-recommended HF therapies for patients encountered in real-world clinical practice,” Dr. Fonarow says. “The findings suggest that there are substantial incremental benefits to applying use of these therapies in outpatient practice settings. Optimizing the use of performance improvement initiatives and disease management programs will help ensure that more hospitals and medical centers are adhering to guideline-recommended therapies to combat HF nationwide.”