麻豆传媒

PARIS – A first look at a massive international registry of treatment for atrial fibrillation indicates that a high percentage of individuals are not being prescribed anticoagulation treatment that can reduce their risk of stroke, researchers said here.

Of the nearly 10,000 patients in the initial cohort of the Global Anticoagulant Registry in the Field (Garfield), CHADS₂ scoring showed 55% of them to be eligible for anticoagulation therapy, but 33% of them didn't get it, Ajay Kakkar, MD, of University College London reported at the European Society of Cardiology meeting.

Guidelines call for treatment with anticoagulation to prevent strokes in patients with CHADS₂ scores of 2 or higher.

When patients were evaluated on the basis of the more sensitive CHADS₂VASc criteria, 81% were eligible for anticoagulation but 36% of them were not receiving it, Kakkar said.

"However you look at these statistics," Kakkar told 麻豆传媒, "they show that more than 50% of patients who are presenting with atrial fibrillation are at high risk for stroke and systemic embolization, yet one-third of them are not being treated."

Kakkar said that, when the researchers examined reasons for failure to anticoagulate, the most frequent response – in 37% of these situations – was that the physician chose not to prescribe it.

He said further research into the reasons why doctors fail to offer anticoagulation to these patients may be elucidated from the registry.

"This is the first look at the registry, representing about 10,000 patients," Kakkar said. "Eventually we will enroll about 55,000 patients into this study – 50,000 of these patients are being enrolled prospectively; 5,000 are enrolled retrospectively."

The Bayer-sponsored registry was designed to describe the real-life patterns of treatment in newly diagnosed atrial fibrillation patients with at least one additional risk factor for stroke.

Patients will be enrolled from 50 countries for a minimum of two years follow-up. The patients are being enrolled consecutively. Initially, the study analyzed 9,288 patients, 4,424 were the retrospectively enrolled individuals but they will be followed prospectively; 4,864 have been enrolled prospectively.

The patient characteristics of the retrospective and prospective cohorts are similar: The mean age of the retrospective cohort is 70.4, about 42% are women; the mean age of the prospective cohort is 69.6 and about 44% are women. Other demographic and health parameters are also similar, Kakkar reported in his symposium lecture.

"One of the problems we face in assessing new drugs," Elliott Antman, MD, of Brigham and Women's Hospital and Harvard Medical School, told 麻豆传媒, "is whether the patients selected for clinical trials are the same types of patients we see in clinical practice."

Antman, who commented on the Garfield Registry report as a spokesperson for the American Heart Association, said that most patients treated in clinical trials for new anticoagulants have CHADS₂ or CHADS₂VASc scores that are 2 or greater. He noted that the registry is showing a similar population in a real-life clinic situation.

"This gives us confidence that the results that were described in the clinical trials will be similar to what we will see in practice," Antman said.

Of the initial patient group in the Garfield Registry, 25% were diagnosed with permanent atrial fibrillation, 18% were diagnosed with persistent atrial fibrillation, 28% were diagnosed with paroxysmal atrial fibrillation, and 30% were newly enrolled patients whose rhythm disturbances have yet to be determined, Kakkar said.

The second cohort of about 10,000 prospectively patients began enrollment Sept. 1, he said.

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