Not all cardiologists treat patients with heart failure and reduced ejection fraction (HFREF) according to established guidelines, and these variations in care are largely due to practice-level factors, according to a study published online Oct. 15 in Circulation: Heart Failure.
Researchers led by Pamela N. Peterson, MD, MSPH, of Denver Health Medical Center, analyzed data from cardiology practices that were part of the National Cardiovascular Disease Registry (NCDR) Practice Innovation and Clinical Excellence (PINNACLE) registry. PINNACLE is an outpatient registry that tracks practice patterns with the goal of helping to improve care.
Peterson and her colleagues obtained treatment information on more then 12,000 HFREF patients (with left ventricular ejection fraction of 40 percent or less) in 43 PINNACLE practices between 2008 and 2010. They determined rates of treatment with ACE inhibitors/ARBs (ACEI/ARB) and beta-blockers (BB) and an optimal combined treatment measure for these patients who had no contraindications. The optimal combined treatment measure was the percentage of patients treated with all medications they were eligible to receive.
An analysis of patient characteristics found that the ACEI/ARB treatment rate was 79 percent, the BB rate was 89 percent and the composite rate was 74 percent. Compared with patients not receiving treatment, ACEI/ARB patients tended to be younger, male and white. They also tended to have a history of stroke, angina and atrial fibrillation, were more likely to have undergone PCI or CABG within the past year and more likely to be treated with antiplatelet therapy.
BB patients were more likely than patients not under treatment to be younger, nonsmokers and to have coronary artery disease (CAD), dyslipidemia, diabetes, prior MI, a CABG within the past year and to be using antiplatelet drugs.
Patients meeting optimal combined treatment measure criteria tended to be younger, male, white, have CAD, dyslipidemia, angina, a recent history of MI or PCI and to be on antiplatelet therapy.
Before adjustment, practice-level prescription rates varied between 44 percent and 100 percent for ACEI/ARB, between 49 percent and 100 percent for BB and between 37 percent to 100 percent for optimal combined treatment.
After adjusting for patient characteristics, there were still practice-level variations. The median rate ratio (MRR) was 1.11 for ACEI/ARB therapy, 1.08 for BB and 1.17 for the combined treatment. Since the effect size of the MRR for each of the treatments was larger than the adjusted odds ratio of any of the patient characteristics, practice factors were likely more strongly associated with treatment.
The authors hypothesized what practice factors could have played a role. Differences in familiarity with guidelines, implementation of tools and systems and the amount of participation time in PINNACLE may have had some impact on the findings.
“Further work is needed to understand the characteristics and processes of high-performing practices and to disseminate those processes to all practices to improve the use of guideline-based therapies for HFREF in the outpatient setting,” they wrote.