What should clinicians do?
In a comment, Gregory Lip, MD, chair of cardiovascular medicine at the University of Liverpool, England, who helped develop the CHA2DS2-VASc score, said clinicians needed to think more broadly when considering hypertension as a risk factor for the score.
He points out that if a patient had a history of hypertension but is now controlled to below 130/80 mm Hg, they would still be considered to be at risk per the CHA2DS2-VASc score.
And for patients without a history of hypertension, and who have a current blood pressure measurement of around 130/80 mm Hg, Dr. Lip advises that it would be premature to diagnose hypertension immediately.
“Hypertension is not a yes/no diagnosis. If you look at the relationship between blood pressure and risk of stroke, it is like a continual dose-response. It doesn’t mean that at 129/79 there is no stroke risk but that at 130/80 there is a stroke risk. It’s not like that,” he said.
“I wouldn’t make a diagnosis on a one-off blood pressure measurement. I would want to monitor that patient and get them to do home measurements,” he commented. “If someone constantly has levels around that 130/80 mm Hg, I don’t necessarily rush in with a definite diagnosis of hypertension and start drug treatment. I would look at lifestyle first. And in such patients, I wouldn’t give them the 1 point for hypertension on the CHA2DS2-VASc score.”
Dr. Lip points out that a hypertension diagnosis is not just about blood pressure numbers. “We have to assess the patients much more completely before giving them a diagnosis and consider factors such as whether there is evidence of hypertension-related end-organ damage, and if lifestyle issues have been addressed.”
Are new risk scores needed?
Dr. Turakhia agreed that clinicians need to look at the bigger picture, but he also suggested that new risk scores may need to be developed.
“All of us in the medical community need to think about whether we should be recalibrating risk prediction with more contemporary evidence – based on our ability to detect disease now,” he commented.
“This could even be a different risk score altogether, possibly incorporating a wider range of parameters or perhaps incorporating machine learning. That’s really the question we need to be asking ourselves,” Dr. Turakhia added.
Dr. Lip noted that there are many stroke risk factors and only those that are most common and have been well validated go into clinical risk scores such as CHA2DS2-VASc.
“These risks scores are by design simplifications, and only have modest predictive value for identifying patients at high risk of stroke. You can always improve on clinical risk scores by adding in other variables,” he said. “There are some risk scores in AF with 26 variables. But the practical application of these more complex scores can be difficult in clinical practice. These risks scores are meant to be simple so that they can be used by busy clinicians in the outpatient clinic or on a ward round. It is not easy to input 26 different variables.”
He also noted that many guidelines are now veering away from categorizing patients at high, medium, or low risk of stroke, which he refers to as “artificial” classifications. “There is now more of a default position that patients should receive stroke prevention normally with a DOAC [direct oral anticoagulant] unless they are low risk.”
Dr. Turakhia agreed that it is imperative to look at the bigger picture when identifying AF patients for anticoagulation. “We have to be careful not to take things at face value. It is more important than ever to use clinical judgment to avoid overtreatment in borderline situations,” he concluded.
This study was supported by the American College of Cardiology Foundation’s National Cardiovascular Data Registry. Dr. Turakhia reported employment from iRhythm Technologies; equity from AliveCor, Connect America, Evidently, and Forward; grants from U.S. Food and Drug Administration, American Heart Association, Bayer, Sanofi, Gilead, and Bristol Myers Squibb; and personal fees from Pfizer and JAMA Cardiology (prior associate editor) outside the submitted work. Dr. Lip has disclosed no relevant financial relationships.
A version of this article first appeared on Medscape.com.