Black patients who have been diagnosed with heart failure are no less likely than white patients to get atrial fibrillation (an irregular heartbeat, or arrhythmia), according to a new study led by researchers in the Perelman School of Medicine at the University of Pennsylvania, which was presented today at the 2014 Scientific Sessions of the American Heart Association. These findings run counter to previous studies, which have found that black patients with heart failure tend to have less atrial fibrillation problems than white patients.
"Even though other studies have found that black patients with heart failure have less atrial fibrillation, we didn't think it made sense," said lead study author Parin J. Patel, MD, an Electrophysiology Fellow at Penn. "We know that heart failure is a major risk factor for atrial fibrillation, even more than old age and high blood pressure, so we set out to understand how there could be such a disparity between races."
The researchers used data from Penn Medicine's internal patient database, Penn Data Store, to find all hospital system patients from 2004 to 2009 who had heart failure, but no history of atrial fibrillation. The resulting data set included 5,131 patients, of which 40 percent were black and 60 percent were white. The median follow-up time with these patients was 4.5 years, during which 16 percent (851 people) developed a new diagnosis of atrial fibrillation, a rate consistent with previous studies. However, counter to previous studies, researchers found that atrial fibrillation rates in this data set were fairly equal among white patients (15 percent) and black patients (18 percent).
While there could be many reasons for previous research showing less atrial fibrillation among black patients, the study authors believe that different follow-up for different groups could have contributed to the prior disparities. In this data set, black patients had more hospital encounters and longer follow-up duration than white patients. The authors also contend that perhaps delivery of care was not optimal in the prior studies. For example, one previous study found that even if physicians diagnosed a black patient with atrial fibrillation, that patient was less likely to know he had atrial fibrillation in a follow-up survey if he was black.
"Our findings are important because they show that physicians should watch out for atrial fibrillation in all heart failure patients, not just those who are white," said Patel. "Future studies in this area are needed to examine other outcomes among this patient population, including heart attack and stroke, and to further understand any differences or similarities between white and black patients."
This is important because the most serious risk from atrial fibrillation is that it can lead to blood clots, heart attack, stroke and other heart-related complications. Treatment for atrial fibrillation is based on the underlying cause, but can include medication to help control the heart rate or catheter ablation to get rid of the arrhythmia, and, therefore, reduce risk for these complications.
Study: 40% of newly diagnosed heart failure patients also have atrial fibrillation