Stroke and bleeding risk co-distribution in real-world patients with atrial fibrillation: the Euro Heart Survey.
BACKGROUND
The choice to recommend antithrombotic therapy to patients with atrial fibrillation should rely on cardioembolic and bleeding risk stratification. Sharing some risk factors, schemes to predict thrombotic and bleeding risk are expected not to be independent, yet the degree of their association has never been clearly quantified.


METHODS
We described the cardioembolic (Congestive heart failure, Hypertension, Age >75, Diabetes mellitus, and prior Stroke or transient ischemic attack [CHADS2]/Congestive heart failure, Hypertension, Age >75, Diabetes mellitus, and prior Stroke or transient ischemic attack, Vascular disease, Age 65-75, Sex category i.e. females [CHA2DS2-VASc]) and bleeding risk (Hypertension, Abnormal renal/liver function, Stroke, Bleeding history or predisposition, Labile international normalized ratio, Elderly (>65 years), Drugs/alcohol concomitantly [HAS-BLED]) co-distribution among patients of the Euro Heart Survey on atrial fibrillation. We measured the within-patient correlation (Spearman) and concordance between the 2 types of score and score-based risk categorization (low, intermediate, high). The score-based predicted risk co-classification was then related to the observed 1-year stroke and bleeding occurrence.


RESULTS
In 3920 patients, we found a between-scores correlation of 0.416 (P < .001) between HAS-BLED and CHADS2, and 0.512 (P < .001) between HAS-BLED and CHA2DS2-VASc. In 89% (CHADS2/HAS-BLED) and 97% (CHA2DS2-VASc/HAS-BLED) of patients, the bleeding risk category was equal to or lower than their cardioembolic risk category (P < .001 for symmetry test). A complete concordance between risk categories was found in 39.6% (CHADS2/HAS-BLED) and 21.7% (CHA2DS2-VASc/HAS-BLED) of patients; 4.4% (CHADS2/HAS-BLED) and 7.7% (CHA2DS2-VASc/HAS-BLED) of patients had high cardioembolic risk/low bleeding risk or vice versa. A tendency for an increasing frequency of stroke was observed for increasing bleeding risk within cardioembolic risk categories and vice versa.


CONCLUSIONS
In a real-world population with atrial fibrillation, we confirmed that the cardioembolic and bleeding risk classifications are correlated but not exchangeable. It is then worth verifying the advantages of a strategy adopting a combined risk assessment over a strategy relying only on the cardioembolic risk evaluation.
Department of Clinical Epidemiology & Biostatistics, McMaster University, Hamilton, Ontario, Canada; Foundation IRCCS Ca' Granda - Ospedale Maggiore Policlinico, Geriatrics & Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy. Electronic address: marcucci.maura@gmail.com.
Maura
M
Marcucci
University of Birmingham Centre for Cardiovascular Sciences, City Hospital, Birmingham, United Kingdom.
Gregory Y H
GY
Lip
Department of Clinical Epidemiology & Biostatistics, McMaster University, Hamilton, Ontario, Canada; Population Health Research Institute, Hamilton, Ontario, Canada.
Robby
R
Nieuwlaat
Department of Cardiology, Maastricht University Medical Centre, Maastricht, The Netherlands.
Ron
R
Pisters
Department of Cardiology, Maastricht University Medical Centre, Maastricht, The Netherlands.
Harry J G M
HJ
Crijns
Department of Clinical Epidemiology & Biostatistics, McMaster University, Hamilton, Ontario, Canada.
Alfonso
A
Iorio
D017677:Age Distribution; D000368:Aged; D000428:Alcohol Drinking / Q000009:adverse effects; D000925:Anticoagulants / Q000009:adverse effects* / Q000627:therapeutic use; D001241:Aspirin / Q000009:adverse effects / Q000627:therapeutic use; D001281:Atrial Fibrillation / Q000150:complications* / Q000188:drug therapy; D048909:Diabetes Complications; D005060:Europe / Q000453:epidemiology; D005260:Female; D006306:Health Surveys; D006333:Heart Failure / Q000209:etiology*; D006470:Hemorrhage / Q000139:chemically induced*; D006801:Humans; D019934:International Normalized Ratio; D008297:Male; D008875:Middle Aged; D018570:Risk Assessment / Q000379:methods / Q000706:statistics & numerical data; D017678:Sex Distribution; D020521:Stroke / Q000209:etiology*; D019966:Substance-Related Disorders / Q000150:complications; D013923:Thromboembolism / Q000150:complications* / Q000517:prevention & control; D014859:Warfarin / Q000009:adverse effects / Q000627:therapeutic use
D000925:Anticoagulants; D014859:Warfarin; D001241:Aspirin
Atrial fibrillation; Cardioembolic and bleeding risk co-stratification