March 29, 2014 – This was the first study to find that having high blood pressure at any point increased the risk of stroke significantly.
High blood pressure is a significant risk factor for stroke in patients who have atrial fibrillation (AF), but most clinical trials to date have focused on AF patients with a history of high blood pressure. In a new sub-analysis of the ARISTOTLE trial, researchers found that AF patients who had uncontrolled blood pressure at any point during the trial had a significantly higher risk of stroke.
The study results were presented at the 2014 American College of Cardiology Scientific Sessions in Washington, D.C. DCRI Fellow Meena Rao, MD, was the lead author.
For this new analysis, researchers identified patients enrolled in the ARISTOTLE trial who had a history of high blood pressure, patients with elevated blood pressure measurements when they were enrolled in the trial, and patients who experienced high blood pressure at any point during the trial.
Researchers confirmed that AF patients with a history of high blood pressure or with elevated readings at enrollment had a greater risk for stroke than patients who did not have high blood pressure. But this was the first study to find that having high blood pressure at any point during the trial significantly increased the risk of stroke by 50 percent.
“In addition to treating with anticoagulants to prevent blood clots, controlling blood pressure in patients with atrial fibrillation is very important to lower the risk of stroke,” said Dr. Rao. “We tend to focus on the use of anticoagulants in these patients, but this study reminds us that blood pressure control is also important for these high-risk patients.”
The sub-analysis also supported the results of the original ARISTOTLE trial in this patient population. The benefit of apixaban when compared to warfarin was consistent regardless of blood pressure control.
“Among patients who have strokes, many studies have found that patients with atrial fibrillation who have a stroke have worse outcomes,” said Dr. Rao. “Preventing strokes in this patient population is very important.”
Other Duke co-authors included Daniel Wojdyla; Christopher Granger, MD; John Alexander, MD; and Renato Lopes, MD, PhD