AT THE AHA SCIENTIFIC SESSIONS
NEW ORLEANS (FRONTLINE MEDICAL NEWS) – Patients who see a cardiologist for their newly diagnosed atrial fibrillation are at significantly lower subsequent risk for ischemic stroke and death than those who receive their care exclusively from primary care physicians, according to a huge Veterans Affairs study.
These superior outcomes were mediated in part by a significantly higher rate of oral anticoagulation prescription within 90 days after diagnosis of atrial fibrillation (AF) among patients who saw a cardiologist, Alexander C. Perino, MD, reported at the American Heart Association scientific sessions.
“The way patients were managed by these two groups of physicians was clearly different. There was a higher rate of early oral anticoagulant prescription in cardiologist-treated patients, and significantly higher rates of both rate and rhythm control therapy as well,” according to Dr. Perino of Stanford (Calif.) University.
He presented results from TREAT-AF (The Retrospective Evaluation and Assessment of Therapies in AF) study, a nationwide Veterans Affairs retrospective observational cohort study including 181,161 patients with newly diagnosed AF during 2003-2012. Forty percent of them saw a cardiologist and often a primary care physician as well, while 60% received all their AF-related care in primary care clinics.
The rate of oral anticoagulant prescription within 90 days of diagnosis of AF was 70.3% in patients seen by cardiologists, compared with 58.8% in those seen by primary care physicians only.
“One way to look at this is to say, ‘Wow, look how great cardiologists are doing.’ Another way to look at it is to say, ‘What is going on here that 30% of atrial fibrillation patients seen by cardiologists are not being given an oral anticoagulant prescription? How do we increase that number?’ That needs to be looked into,” Dr. Perino said.
The incidence of ischemic stroke was 7.6 per 1,000 person-years in the cardiology group, significantly lower than the 8.8 per 1,000 in the primary care–only group.
While the two groups shared similar CHA2DS2-VASc scores, the cohort seen by cardiologists had significantly higher rates of comorbid diabetes, hypertension, coronary artery disease, prior MI, and stroke.
In a multivariate analysis adjusted for these comorbidities as well as patient demographics, distance to VA medical care, and use of medications other than oral anticoagulants, cardiology care was associated with a 9% relative risk reduction in ischemic stroke, an 11% reduction in all-cause mortality, and a 3% increase in MI, all statistically significant.
In a more sophisticated analysis featuring propensity score matching, the cardiology group had a 12% relative risk reduction in stroke and a 10% reduction in the risk of death.
The investigators determined that 17% of the improvement in outcomes seen in the cardiology group was attributable to their higher rate of early anticoagulant therapy. Another potential contributor to the outcome differences might be cardiologists’ greater use of rate and rhythm control: Rate control medication was prescribed for 90.1% of the cardiology patients, compared with 80.5% of the primary care patients. And rhythm control therapy was prescribed for 20.8% of the cardiology group versus just 11% of the primary care–only patients.
It’s also possible that cardiology care had a differential impact on non-AF conditions, although this is speculation, Dr. Perino noted.
He said it’s unrealistic to propose that all patients with newly diagnosed AF be seen by a cardiologist because the cardiology workforce isn’t big enough. But more widespread use of specialized AF clinics staffed by expert nurse practitioners and physician assistants could be a practical way for health care plans to achieve cardiologylike outcomes in patients with newly diagnosed AF, in his view.
Dr. Perino reported having no financial conflicts of interest regarding his study.
